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Diffstat (limited to 'src/org/jivesoftware/smack/util/collections')
13 files changed, 3201 insertions, 0 deletions
diff --git a/src/org/jivesoftware/smack/util/collections/AbstractEmptyIterator.java b/src/org/jivesoftware/smack/util/collections/AbstractEmptyIterator.java new file mode 100644 index 0000000..c2ec156 --- /dev/null +++ b/src/org/jivesoftware/smack/util/collections/AbstractEmptyIterator.java @@ -0,0 +1,89 @@ +// GenericsNote: Converted. +/* + * Copyright 2004 The Apache Software Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.jivesoftware.smack.util.collections; + +import java.util.NoSuchElementException; + +/** + * Provides an implementation of an empty iterator. + * + * @author Matt Hall, John Watkinson, Stephen Colebourne + * @version $Revision: 1.1 $ $Date: 2005/10/11 17:05:24 $ + * @since Commons Collections 3.1 + */ +abstract class AbstractEmptyIterator <E> { + + /** + * Constructor. + */ + protected AbstractEmptyIterator() { + super(); + } + + public boolean hasNext() { + return false; + } + + public E next() { + throw new NoSuchElementException("Iterator contains no elements"); + } + + public boolean hasPrevious() { + return false; + } + + public E previous() { + throw new NoSuchElementException("Iterator contains no elements"); + } + + public int nextIndex() { + return 0; + } + + public int previousIndex() { + return -1; + } + + public void add(E obj) { + throw new UnsupportedOperationException("add() not supported for empty Iterator"); + } + + public void set(E obj) { + throw new IllegalStateException("Iterator contains no elements"); + } + + public void remove() { + throw new IllegalStateException("Iterator contains no elements"); + } + + public E getKey() { + throw new IllegalStateException("Iterator contains no elements"); + } + + public E getValue() { + throw new IllegalStateException("Iterator contains no elements"); + } + + public E setValue(E value) { + throw new IllegalStateException("Iterator contains no elements"); + } + + public void reset() { + // do nothing + } + +} diff --git a/src/org/jivesoftware/smack/util/collections/AbstractHashedMap.java b/src/org/jivesoftware/smack/util/collections/AbstractHashedMap.java new file mode 100644 index 0000000..f6fb34a --- /dev/null +++ b/src/org/jivesoftware/smack/util/collections/AbstractHashedMap.java @@ -0,0 +1,1338 @@ +// GenericsNote: Converted -- However, null keys will now be represented in the internal structures, a big change. +/* + * Copyright 2003-2004 The Apache Software Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.jivesoftware.smack.util.collections; + +import java.io.IOException; +import java.io.ObjectInputStream; +import java.io.ObjectOutputStream; +import java.util.*; + +/** + * An abstract implementation of a hash-based map which provides numerous points for + * subclasses to override. + * <p/> + * This class implements all the features necessary for a subclass hash-based map. + * Key-value entries are stored in instances of the <code>HashEntry</code> class, + * which can be overridden and replaced. The iterators can similarly be replaced, + * without the need to replace the KeySet, EntrySet and Values view classes. + * <p/> + * Overridable methods are provided to change the default hashing behaviour, and + * to change how entries are added to and removed from the map. Hopefully, all you + * need for unusual subclasses is here. + * <p/> + * NOTE: From Commons Collections 3.1 this class extends AbstractMap. + * This is to provide backwards compatibility for ReferenceMap between v3.0 and v3.1. + * This extends clause will be removed in v4.0. + * + * @author java util HashMap + * @author Matt Hall, John Watkinson, Stephen Colebourne + * @version $Revision: 1.1 $ $Date: 2005/10/11 17:05:32 $ + * @since Commons Collections 3.0 + */ +public class AbstractHashedMap <K,V> extends AbstractMap<K, V> implements IterableMap<K, V> { + + protected static final String NO_NEXT_ENTRY = "No next() entry in the iteration"; + protected static final String NO_PREVIOUS_ENTRY = "No previous() entry in the iteration"; + protected static final String REMOVE_INVALID = "remove() can only be called once after next()"; + protected static final String GETKEY_INVALID = "getKey() can only be called after next() and before remove()"; + protected static final String GETVALUE_INVALID = "getValue() can only be called after next() and before remove()"; + protected static final String SETVALUE_INVALID = "setValue() can only be called after next() and before remove()"; + + /** + * The default capacity to use + */ + protected static final int DEFAULT_CAPACITY = 16; + /** + * The default threshold to use + */ + protected static final int DEFAULT_THRESHOLD = 12; + /** + * The default load factor to use + */ + protected static final float DEFAULT_LOAD_FACTOR = 0.75f; + /** + * The maximum capacity allowed + */ + protected static final int MAXIMUM_CAPACITY = 1 << 30; + /** + * An object for masking null + */ + protected static final Object NULL = new Object(); + + /** + * Load factor, normally 0.75 + */ + protected transient float loadFactor; + /** + * The size of the map + */ + protected transient int size; + /** + * Map entries + */ + protected transient HashEntry<K, V>[] data; + /** + * Size at which to rehash + */ + protected transient int threshold; + /** + * Modification count for iterators + */ + protected transient int modCount; + /** + * Entry set + */ + protected transient EntrySet<K, V> entrySet; + /** + * Key set + */ + protected transient KeySet<K, V> keySet; + /** + * Values + */ + protected transient Values<K, V> values; + + /** + * Constructor only used in deserialization, do not use otherwise. + */ + protected AbstractHashedMap() { + super(); + } + + /** + * Constructor which performs no validation on the passed in parameters. + * + * @param initialCapacity the initial capacity, must be a power of two + * @param loadFactor the load factor, must be > 0.0f and generally < 1.0f + * @param threshold the threshold, must be sensible + */ + protected AbstractHashedMap(int initialCapacity, float loadFactor, int threshold) { + super(); + this.loadFactor = loadFactor; + this.data = new HashEntry[initialCapacity]; + this.threshold = threshold; + init(); + } + + /** + * Constructs a new, empty map with the specified initial capacity and + * default load factor. + * + * @param initialCapacity the initial capacity + * @throws IllegalArgumentException if the initial capacity is less than one + */ + protected AbstractHashedMap(int initialCapacity) { + this(initialCapacity, DEFAULT_LOAD_FACTOR); + } + + /** + * Constructs a new, empty map with the specified initial capacity and + * load factor. + * + * @param initialCapacity the initial capacity + * @param loadFactor the load factor + * @throws IllegalArgumentException if the initial capacity is less than one + * @throws IllegalArgumentException if the load factor is less than or equal to zero + */ + protected AbstractHashedMap(int initialCapacity, float loadFactor) { + super(); + if (initialCapacity < 1) { + throw new IllegalArgumentException("Initial capacity must be greater than 0"); + } + if (loadFactor <= 0.0f || Float.isNaN(loadFactor)) { + throw new IllegalArgumentException("Load factor must be greater than 0"); + } + this.loadFactor = loadFactor; + this.threshold = calculateThreshold(initialCapacity, loadFactor); + initialCapacity = calculateNewCapacity(initialCapacity); + this.data = new HashEntry[initialCapacity]; + init(); + } + + /** + * Constructor copying elements from another map. + * + * @param map the map to copy + * @throws NullPointerException if the map is null + */ + protected AbstractHashedMap(Map<? extends K, ? extends V> map) { + this(Math.max(2 * map.size(), DEFAULT_CAPACITY), DEFAULT_LOAD_FACTOR); + putAll(map); + } + + /** + * Initialise subclasses during construction, cloning or deserialization. + */ + protected void init() { + } + + //----------------------------------------------------------------------- + /** + * Gets the value mapped to the key specified. + * + * @param key the key + * @return the mapped value, null if no match + */ + public V get(Object key) { + int hashCode = hash((key == null) ? NULL : key); + HashEntry<K, V> entry = data[hashIndex(hashCode, data.length)]; // no local for hash index + while (entry != null) { + if (entry.hashCode == hashCode && isEqualKey(key, entry.key)) { + return entry.getValue(); + } + entry = entry.next; + } + return null; + } + + /** + * Gets the size of the map. + * + * @return the size + */ + public int size() { + return size; + } + + /** + * Checks whether the map is currently empty. + * + * @return true if the map is currently size zero + */ + public boolean isEmpty() { + return (size == 0); + } + + //----------------------------------------------------------------------- + /** + * Checks whether the map contains the specified key. + * + * @param key the key to search for + * @return true if the map contains the key + */ + public boolean containsKey(Object key) { + int hashCode = hash((key == null) ? NULL : key); + HashEntry entry = data[hashIndex(hashCode, data.length)]; // no local for hash index + while (entry != null) { + if (entry.hashCode == hashCode && isEqualKey(key, entry.getKey())) { + return true; + } + entry = entry.next; + } + return false; + } + + /** + * Checks whether the map contains the specified value. + * + * @param value the value to search for + * @return true if the map contains the value + */ + public boolean containsValue(Object value) { + if (value == null) { + for (int i = 0, isize = data.length; i < isize; i++) { + HashEntry entry = data[i]; + while (entry != null) { + if (entry.getValue() == null) { + return true; + } + entry = entry.next; + } + } + } else { + for (int i = 0, isize = data.length; i < isize; i++) { + HashEntry entry = data[i]; + while (entry != null) { + if (isEqualValue(value, entry.getValue())) { + return true; + } + entry = entry.next; + } + } + } + return false; + } + + //----------------------------------------------------------------------- + /** + * Puts a key-value mapping into this map. + * + * @param key the key to add + * @param value the value to add + * @return the value previously mapped to this key, null if none + */ + public V put(K key, V value) { + int hashCode = hash((key == null) ? NULL : key); + int index = hashIndex(hashCode, data.length); + HashEntry<K, V> entry = data[index]; + while (entry != null) { + if (entry.hashCode == hashCode && isEqualKey(key, entry.getKey())) { + V oldValue = entry.getValue(); + updateEntry(entry, value); + return oldValue; + } + entry = entry.next; + } + addMapping(index, hashCode, key, value); + return null; + } + + /** + * Puts all the values from the specified map into this map. + * <p/> + * This implementation iterates around the specified map and + * uses {@link #put(Object, Object)}. + * + * @param map the map to add + * @throws NullPointerException if the map is null + */ + public void putAll(Map<? extends K, ? extends V> map) { + int mapSize = map.size(); + if (mapSize == 0) { + return; + } + int newSize = (int) ((size + mapSize) / loadFactor + 1); + ensureCapacity(calculateNewCapacity(newSize)); + // Have to cast here because of compiler inference problems. + for (Iterator it = map.entrySet().iterator(); it.hasNext();) { + Map.Entry<? extends K, ? extends V> entry = (Map.Entry<? extends K, ? extends V>) it.next(); + put(entry.getKey(), entry.getValue()); + } + } + + /** + * Removes the specified mapping from this map. + * + * @param key the mapping to remove + * @return the value mapped to the removed key, null if key not in map + */ + public V remove(Object key) { + int hashCode = hash((key == null) ? NULL : key); + int index = hashIndex(hashCode, data.length); + HashEntry<K, V> entry = data[index]; + HashEntry<K, V> previous = null; + while (entry != null) { + if (entry.hashCode == hashCode && isEqualKey(key, entry.getKey())) { + V oldValue = entry.getValue(); + removeMapping(entry, index, previous); + return oldValue; + } + previous = entry; + entry = entry.next; + } + return null; + } + + /** + * Clears the map, resetting the size to zero and nullifying references + * to avoid garbage collection issues. + */ + public void clear() { + modCount++; + HashEntry[] data = this.data; + for (int i = data.length - 1; i >= 0; i--) { + data[i] = null; + } + size = 0; + } + + /** + * Gets the hash code for the key specified. + * This implementation uses the additional hashing routine from JDK1.4. + * Subclasses can override this to return alternate hash codes. + * + * @param key the key to get a hash code for + * @return the hash code + */ + protected int hash(Object key) { + // same as JDK 1.4 + int h = key.hashCode(); + h += ~(h << 9); + h ^= (h >>> 14); + h += (h << 4); + h ^= (h >>> 10); + return h; + } + + /** + * Compares two keys, in internal converted form, to see if they are equal. + * This implementation uses the equals method. + * Subclasses can override this to match differently. + * + * @param key1 the first key to compare passed in from outside + * @param key2 the second key extracted from the entry via <code>entry.key</code> + * @return true if equal + */ + protected boolean isEqualKey(Object key1, Object key2) { + return (key1 == key2 || ((key1 != null) && key1.equals(key2))); + } + + /** + * Compares two values, in external form, to see if they are equal. + * This implementation uses the equals method and assumes neither value is null. + * Subclasses can override this to match differently. + * + * @param value1 the first value to compare passed in from outside + * @param value2 the second value extracted from the entry via <code>getValue()</code> + * @return true if equal + */ + protected boolean isEqualValue(Object value1, Object value2) { + return (value1 == value2 || value1.equals(value2)); + } + + /** + * Gets the index into the data storage for the hashCode specified. + * This implementation uses the least significant bits of the hashCode. + * Subclasses can override this to return alternate bucketing. + * + * @param hashCode the hash code to use + * @param dataSize the size of the data to pick a bucket from + * @return the bucket index + */ + protected int hashIndex(int hashCode, int dataSize) { + return hashCode & (dataSize - 1); + } + + //----------------------------------------------------------------------- + /** + * Gets the entry mapped to the key specified. + * <p/> + * This method exists for subclasses that may need to perform a multi-step + * process accessing the entry. The public methods in this class don't use this + * method to gain a small performance boost. + * + * @param key the key + * @return the entry, null if no match + */ + protected HashEntry<K, V> getEntry(Object key) { + int hashCode = hash((key == null) ? NULL : key); + HashEntry<K, V> entry = data[hashIndex(hashCode, data.length)]; // no local for hash index + while (entry != null) { + if (entry.hashCode == hashCode && isEqualKey(key, entry.getKey())) { + return entry; + } + entry = entry.next; + } + return null; + } + + //----------------------------------------------------------------------- + /** + * Updates an existing key-value mapping to change the value. + * <p/> + * This implementation calls <code>setValue()</code> on the entry. + * Subclasses could override to handle changes to the map. + * + * @param entry the entry to update + * @param newValue the new value to store + */ + protected void updateEntry(HashEntry<K, V> entry, V newValue) { + entry.setValue(newValue); + } + + /** + * Reuses an existing key-value mapping, storing completely new data. + * <p/> + * This implementation sets all the data fields on the entry. + * Subclasses could populate additional entry fields. + * + * @param entry the entry to update, not null + * @param hashIndex the index in the data array + * @param hashCode the hash code of the key to add + * @param key the key to add + * @param value the value to add + */ + protected void reuseEntry(HashEntry<K, V> entry, int hashIndex, int hashCode, K key, V value) { + entry.next = data[hashIndex]; + entry.hashCode = hashCode; + entry.key = key; + entry.value = value; + } + + //----------------------------------------------------------------------- + /** + * Adds a new key-value mapping into this map. + * <p/> + * This implementation calls <code>createEntry()</code>, <code>addEntry()</code> + * and <code>checkCapacity()</code>. + * It also handles changes to <code>modCount</code> and <code>size</code>. + * Subclasses could override to fully control adds to the map. + * + * @param hashIndex the index into the data array to store at + * @param hashCode the hash code of the key to add + * @param key the key to add + * @param value the value to add + */ + protected void addMapping(int hashIndex, int hashCode, K key, V value) { + modCount++; + HashEntry<K, V> entry = createEntry(data[hashIndex], hashCode, key, value); + addEntry(entry, hashIndex); + size++; + checkCapacity(); + } + + /** + * Creates an entry to store the key-value data. + * <p/> + * This implementation creates a new HashEntry instance. + * Subclasses can override this to return a different storage class, + * or implement caching. + * + * @param next the next entry in sequence + * @param hashCode the hash code to use + * @param key the key to store + * @param value the value to store + * @return the newly created entry + */ + protected HashEntry<K, V> createEntry(HashEntry<K, V> next, int hashCode, K key, V value) { + return new HashEntry<K, V>(next, hashCode, key, value); + } + + /** + * Adds an entry into this map. + * <p/> + * This implementation adds the entry to the data storage table. + * Subclasses could override to handle changes to the map. + * + * @param entry the entry to add + * @param hashIndex the index into the data array to store at + */ + protected void addEntry(HashEntry<K, V> entry, int hashIndex) { + data[hashIndex] = entry; + } + + //----------------------------------------------------------------------- + /** + * Removes a mapping from the map. + * <p/> + * This implementation calls <code>removeEntry()</code> and <code>destroyEntry()</code>. + * It also handles changes to <code>modCount</code> and <code>size</code>. + * Subclasses could override to fully control removals from the map. + * + * @param entry the entry to remove + * @param hashIndex the index into the data structure + * @param previous the previous entry in the chain + */ + protected void removeMapping(HashEntry<K, V> entry, int hashIndex, HashEntry<K, V> previous) { + modCount++; + removeEntry(entry, hashIndex, previous); + size--; + destroyEntry(entry); + } + + /** + * Removes an entry from the chain stored in a particular index. + * <p/> + * This implementation removes the entry from the data storage table. + * The size is not updated. + * Subclasses could override to handle changes to the map. + * + * @param entry the entry to remove + * @param hashIndex the index into the data structure + * @param previous the previous entry in the chain + */ + protected void removeEntry(HashEntry<K, V> entry, int hashIndex, HashEntry<K, V> previous) { + if (previous == null) { + data[hashIndex] = entry.next; + } else { + previous.next = entry.next; + } + } + + /** + * Kills an entry ready for the garbage collector. + * <p/> + * This implementation prepares the HashEntry for garbage collection. + * Subclasses can override this to implement caching (override clear as well). + * + * @param entry the entry to destroy + */ + protected void destroyEntry(HashEntry<K, V> entry) { + entry.next = null; + entry.key = null; + entry.value = null; + } + + //----------------------------------------------------------------------- + /** + * Checks the capacity of the map and enlarges it if necessary. + * <p/> + * This implementation uses the threshold to check if the map needs enlarging + */ + protected void checkCapacity() { + if (size >= threshold) { + int newCapacity = data.length * 2; + if (newCapacity <= MAXIMUM_CAPACITY) { + ensureCapacity(newCapacity); + } + } + } + + /** + * Changes the size of the data structure to the capacity proposed. + * + * @param newCapacity the new capacity of the array (a power of two, less or equal to max) + */ + protected void ensureCapacity(int newCapacity) { + int oldCapacity = data.length; + if (newCapacity <= oldCapacity) { + return; + } + if (size == 0) { + threshold = calculateThreshold(newCapacity, loadFactor); + data = new HashEntry[newCapacity]; + } else { + HashEntry<K, V> oldEntries[] = data; + HashEntry<K, V> newEntries[] = new HashEntry[newCapacity]; + + modCount++; + for (int i = oldCapacity - 1; i >= 0; i--) { + HashEntry<K, V> entry = oldEntries[i]; + if (entry != null) { + oldEntries[i] = null; // gc + do { + HashEntry<K, V> next = entry.next; + int index = hashIndex(entry.hashCode, newCapacity); + entry.next = newEntries[index]; + newEntries[index] = entry; + entry = next; + } while (entry != null); + } + } + threshold = calculateThreshold(newCapacity, loadFactor); + data = newEntries; + } + } + + /** + * Calculates the new capacity of the map. + * This implementation normalizes the capacity to a power of two. + * + * @param proposedCapacity the proposed capacity + * @return the normalized new capacity + */ + protected int calculateNewCapacity(int proposedCapacity) { + int newCapacity = 1; + if (proposedCapacity > MAXIMUM_CAPACITY) { + newCapacity = MAXIMUM_CAPACITY; + } else { + while (newCapacity < proposedCapacity) { + newCapacity <<= 1; // multiply by two + } + if (newCapacity > MAXIMUM_CAPACITY) { + newCapacity = MAXIMUM_CAPACITY; + } + } + return newCapacity; + } + + /** + * Calculates the new threshold of the map, where it will be resized. + * This implementation uses the load factor. + * + * @param newCapacity the new capacity + * @param factor the load factor + * @return the new resize threshold + */ + protected int calculateThreshold(int newCapacity, float factor) { + return (int) (newCapacity * factor); + } + + //----------------------------------------------------------------------- + /** + * Gets the <code>next</code> field from a <code>HashEntry</code>. + * Used in subclasses that have no visibility of the field. + * + * @param entry the entry to query, must not be null + * @return the <code>next</code> field of the entry + * @throws NullPointerException if the entry is null + * @since Commons Collections 3.1 + */ + protected HashEntry<K, V> entryNext(HashEntry<K, V> entry) { + return entry.next; + } + + /** + * Gets the <code>hashCode</code> field from a <code>HashEntry</code>. + * Used in subclasses that have no visibility of the field. + * + * @param entry the entry to query, must not be null + * @return the <code>hashCode</code> field of the entry + * @throws NullPointerException if the entry is null + * @since Commons Collections 3.1 + */ + protected int entryHashCode(HashEntry<K, V> entry) { + return entry.hashCode; + } + + /** + * Gets the <code>key</code> field from a <code>HashEntry</code>. + * Used in subclasses that have no visibility of the field. + * + * @param entry the entry to query, must not be null + * @return the <code>key</code> field of the entry + * @throws NullPointerException if the entry is null + * @since Commons Collections 3.1 + */ + protected K entryKey(HashEntry<K, V> entry) { + return entry.key; + } + + /** + * Gets the <code>value</code> field from a <code>HashEntry</code>. + * Used in subclasses that have no visibility of the field. + * + * @param entry the entry to query, must not be null + * @return the <code>value</code> field of the entry + * @throws NullPointerException if the entry is null + * @since Commons Collections 3.1 + */ + protected V entryValue(HashEntry<K, V> entry) { + return entry.value; + } + + //----------------------------------------------------------------------- + /** + * Gets an iterator over the map. + * Changes made to the iterator affect this map. + * <p/> + * A MapIterator returns the keys in the map. It also provides convenient + * methods to get the key and value, and set the value. + * It avoids the need to create an entrySet/keySet/values object. + * It also avoids creating the Map.Entry object. + * + * @return the map iterator + */ + public MapIterator<K, V> mapIterator() { + if (size == 0) { + return EmptyMapIterator.INSTANCE; + } + return new HashMapIterator<K, V>(this); + } + + /** + * MapIterator implementation. + */ + protected static class HashMapIterator <K,V> extends HashIterator<K, V> implements MapIterator<K, V> { + + protected HashMapIterator(AbstractHashedMap<K, V> parent) { + super(parent); + } + + public K next() { + return super.nextEntry().getKey(); + } + + public K getKey() { + HashEntry<K, V> current = currentEntry(); + if (current == null) { + throw new IllegalStateException(AbstractHashedMap.GETKEY_INVALID); + } + return current.getKey(); + } + + public V getValue() { + HashEntry<K, V> current = currentEntry(); + if (current == null) { + throw new IllegalStateException(AbstractHashedMap.GETVALUE_INVALID); + } + return current.getValue(); + } + + public V setValue(V value) { + HashEntry<K, V> current = currentEntry(); + if (current == null) { + throw new IllegalStateException(AbstractHashedMap.SETVALUE_INVALID); + } + return current.setValue(value); + } + } + + //----------------------------------------------------------------------- + /** + * Gets the entrySet view of the map. + * Changes made to the view affect this map. + * To simply iterate through the entries, use {@link #mapIterator()}. + * + * @return the entrySet view + */ + public Set<Map.Entry<K, V>> entrySet() { + if (entrySet == null) { + entrySet = new EntrySet<K, V>(this); + } + return entrySet; + } + + /** + * Creates an entry set iterator. + * Subclasses can override this to return iterators with different properties. + * + * @return the entrySet iterator + */ + protected Iterator<Map.Entry<K, V>> createEntrySetIterator() { + if (size() == 0) { + return EmptyIterator.INSTANCE; + } + return new EntrySetIterator<K, V>(this); + } + + /** + * EntrySet implementation. + */ + protected static class EntrySet <K,V> extends AbstractSet<Map.Entry<K, V>> { + /** + * The parent map + */ + protected final AbstractHashedMap<K, V> parent; + + protected EntrySet(AbstractHashedMap<K, V> parent) { + super(); + this.parent = parent; + } + + public int size() { + return parent.size(); + } + + public void clear() { + parent.clear(); + } + + public boolean contains(Map.Entry<K, V> entry) { + Map.Entry<K, V> e = entry; + Entry<K, V> match = parent.getEntry(e.getKey()); + return (match != null && match.equals(e)); + } + + public boolean remove(Object obj) { + if (obj instanceof Map.Entry == false) { + return false; + } + if (contains(obj) == false) { + return false; + } + Map.Entry<K, V> entry = (Map.Entry<K, V>) obj; + K key = entry.getKey(); + parent.remove(key); + return true; + } + + public Iterator<Map.Entry<K, V>> iterator() { + return parent.createEntrySetIterator(); + } + } + + /** + * EntrySet iterator. + */ + protected static class EntrySetIterator <K,V> extends HashIterator<K, V> implements Iterator<Map.Entry<K, V>> { + + protected EntrySetIterator(AbstractHashedMap<K, V> parent) { + super(parent); + } + + public HashEntry<K, V> next() { + return super.nextEntry(); + } + } + + //----------------------------------------------------------------------- + /** + * Gets the keySet view of the map. + * Changes made to the view affect this map. + * To simply iterate through the keys, use {@link #mapIterator()}. + * + * @return the keySet view + */ + public Set<K> keySet() { + if (keySet == null) { + keySet = new KeySet<K, V>(this); + } + return keySet; + } + + /** + * Creates a key set iterator. + * Subclasses can override this to return iterators with different properties. + * + * @return the keySet iterator + */ + protected Iterator<K> createKeySetIterator() { + if (size() == 0) { + return EmptyIterator.INSTANCE; + } + return new KeySetIterator<K, V>(this); + } + + /** + * KeySet implementation. + */ + protected static class KeySet <K,V> extends AbstractSet<K> { + /** + * The parent map + */ + protected final AbstractHashedMap<K, V> parent; + + protected KeySet(AbstractHashedMap<K, V> parent) { + super(); + this.parent = parent; + } + + public int size() { + return parent.size(); + } + + public void clear() { + parent.clear(); + } + + public boolean contains(Object key) { + return parent.containsKey(key); + } + + public boolean remove(Object key) { + boolean result = parent.containsKey(key); + parent.remove(key); + return result; + } + + public Iterator<K> iterator() { + return parent.createKeySetIterator(); + } + } + + /** + * KeySet iterator. + */ + protected static class KeySetIterator <K,V> extends HashIterator<K, V> implements Iterator<K> { + + protected KeySetIterator(AbstractHashedMap<K, V> parent) { + super(parent); + } + + public K next() { + return super.nextEntry().getKey(); + } + } + + //----------------------------------------------------------------------- + /** + * Gets the values view of the map. + * Changes made to the view affect this map. + * To simply iterate through the values, use {@link #mapIterator()}. + * + * @return the values view + */ + public Collection<V> values() { + if (values == null) { + values = new Values(this); + } + return values; + } + + /** + * Creates a values iterator. + * Subclasses can override this to return iterators with different properties. + * + * @return the values iterator + */ + protected Iterator<V> createValuesIterator() { + if (size() == 0) { + return EmptyIterator.INSTANCE; + } + return new ValuesIterator<K, V>(this); + } + + /** + * Values implementation. + */ + protected static class Values <K,V> extends AbstractCollection<V> { + /** + * The parent map + */ + protected final AbstractHashedMap<K, V> parent; + + protected Values(AbstractHashedMap<K, V> parent) { + super(); + this.parent = parent; + } + + public int size() { + return parent.size(); + } + + public void clear() { + parent.clear(); + } + + public boolean contains(Object value) { + return parent.containsValue(value); + } + + public Iterator<V> iterator() { + return parent.createValuesIterator(); + } + } + + /** + * Values iterator. + */ + protected static class ValuesIterator <K,V> extends HashIterator<K, V> implements Iterator<V> { + + protected ValuesIterator(AbstractHashedMap<K, V> parent) { + super(parent); + } + + public V next() { + return super.nextEntry().getValue(); + } + } + + //----------------------------------------------------------------------- + /** + * HashEntry used to store the data. + * <p/> + * If you subclass <code>AbstractHashedMap</code> but not <code>HashEntry</code> + * then you will not be able to access the protected fields. + * The <code>entryXxx()</code> methods on <code>AbstractHashedMap</code> exist + * to provide the necessary access. + */ + protected static class HashEntry <K,V> implements Map.Entry<K, V>, KeyValue<K, V> { + /** + * The next entry in the hash chain + */ + protected HashEntry<K, V> next; + /** + * The hash code of the key + */ + protected int hashCode; + /** + * The key + */ + private K key; + /** + * The value + */ + private V value; + + protected HashEntry(HashEntry<K, V> next, int hashCode, K key, V value) { + super(); + this.next = next; + this.hashCode = hashCode; + this.key = key; + this.value = value; + } + + public K getKey() { + return key; + } + + public void setKey(K key) { + this.key = key; + } + + public V getValue() { + return value; + } + + public V setValue(V value) { + V old = this.value; + this.value = value; + return old; + } + + public boolean equals(Object obj) { + if (obj == this) { + return true; + } + if (obj instanceof Map.Entry == false) { + return false; + } + Map.Entry other = (Map.Entry) obj; + return (getKey() == null ? other.getKey() == null : getKey().equals(other.getKey())) && (getValue() == null ? other.getValue() == null : getValue().equals(other.getValue())); + } + + public int hashCode() { + return (getKey() == null ? 0 : getKey().hashCode()) ^ (getValue() == null ? 0 : getValue().hashCode()); + } + + public String toString() { + return new StringBuilder().append(getKey()).append('=').append(getValue()).toString(); + } + } + + /** + * Base Iterator + */ + protected static abstract class HashIterator <K,V> { + + /** + * The parent map + */ + protected final AbstractHashedMap parent; + /** + * The current index into the array of buckets + */ + protected int hashIndex; + /** + * The last returned entry + */ + protected HashEntry<K, V> last; + /** + * The next entry + */ + protected HashEntry<K, V> next; + /** + * The modification count expected + */ + protected int expectedModCount; + + protected HashIterator(AbstractHashedMap<K, V> parent) { + super(); + this.parent = parent; + HashEntry<K, V>[] data = parent.data; + int i = data.length; + HashEntry<K, V> next = null; + while (i > 0 && next == null) { + next = data[--i]; + } + this.next = next; + this.hashIndex = i; + this.expectedModCount = parent.modCount; + } + + public boolean hasNext() { + return (next != null); + } + + protected HashEntry<K, V> nextEntry() { + if (parent.modCount != expectedModCount) { + throw new ConcurrentModificationException(); + } + HashEntry<K, V> newCurrent = next; + if (newCurrent == null) { + throw new NoSuchElementException(AbstractHashedMap.NO_NEXT_ENTRY); + } + HashEntry<K, V>[] data = parent.data; + int i = hashIndex; + HashEntry<K, V> n = newCurrent.next; + while (n == null && i > 0) { + n = data[--i]; + } + next = n; + hashIndex = i; + last = newCurrent; + return newCurrent; + } + + protected HashEntry<K, V> currentEntry() { + return last; + } + + public void remove() { + if (last == null) { + throw new IllegalStateException(AbstractHashedMap.REMOVE_INVALID); + } + if (parent.modCount != expectedModCount) { + throw new ConcurrentModificationException(); + } + parent.remove(last.getKey()); + last = null; + expectedModCount = parent.modCount; + } + + public String toString() { + if (last != null) { + return "Iterator[" + last.getKey() + "=" + last.getValue() + "]"; + } else { + return "Iterator[]"; + } + } + } + + //----------------------------------------------------------------------- + /** + * Writes the map data to the stream. This method must be overridden if a + * subclass must be setup before <code>put()</code> is used. + * <p/> + * Serialization is not one of the JDK's nicest topics. Normal serialization will + * initialise the superclass before the subclass. Sometimes however, this isn't + * what you want, as in this case the <code>put()</code> method on read can be + * affected by subclass state. + * <p/> + * The solution adopted here is to serialize the state data of this class in + * this protected method. This method must be called by the + * <code>writeObject()</code> of the first serializable subclass. + * <p/> + * Subclasses may override if they have a specific field that must be present + * on read before this implementation will work. Generally, the read determines + * what must be serialized here, if anything. + * + * @param out the output stream + */ + protected void doWriteObject(ObjectOutputStream out) throws IOException { + out.writeFloat(loadFactor); + out.writeInt(data.length); + out.writeInt(size); + for (MapIterator it = mapIterator(); it.hasNext();) { + out.writeObject(it.next()); + out.writeObject(it.getValue()); + } + } + + /** + * Reads the map data from the stream. This method must be overridden if a + * subclass must be setup before <code>put()</code> is used. + * <p/> + * Serialization is not one of the JDK's nicest topics. Normal serialization will + * initialise the superclass before the subclass. Sometimes however, this isn't + * what you want, as in this case the <code>put()</code> method on read can be + * affected by subclass state. + * <p/> + * The solution adopted here is to deserialize the state data of this class in + * this protected method. This method must be called by the + * <code>readObject()</code> of the first serializable subclass. + * <p/> + * Subclasses may override if the subclass has a specific field that must be present + * before <code>put()</code> or <code>calculateThreshold()</code> will work correctly. + * + * @param in the input stream + */ + protected void doReadObject(ObjectInputStream in) throws IOException, ClassNotFoundException { + loadFactor = in.readFloat(); + int capacity = in.readInt(); + int size = in.readInt(); + init(); + data = new HashEntry[capacity]; + for (int i = 0; i < size; i++) { + K key = (K) in.readObject(); + V value = (V) in.readObject(); + put(key, value); + } + threshold = calculateThreshold(data.length, loadFactor); + } + + //----------------------------------------------------------------------- + /** + * Clones the map without cloning the keys or values. + * <p/> + * To implement <code>clone()</code>, a subclass must implement the + * <code>Cloneable</code> interface and make this method public. + * + * @return a shallow clone + */ + protected Object clone() { + try { + AbstractHashedMap cloned = (AbstractHashedMap) super.clone(); + cloned.data = new HashEntry[data.length]; + cloned.entrySet = null; + cloned.keySet = null; + cloned.values = null; + cloned.modCount = 0; + cloned.size = 0; + cloned.init(); + cloned.putAll(this); + return cloned; + + } catch (CloneNotSupportedException ex) { + return null; // should never happen + } + } + + /** + * Compares this map with another. + * + * @param obj the object to compare to + * @return true if equal + */ + public boolean equals(Object obj) { + if (obj == this) { + return true; + } + if (obj instanceof Map == false) { + return false; + } + Map map = (Map) obj; + if (map.size() != size()) { + return false; + } + MapIterator it = mapIterator(); + try { + while (it.hasNext()) { + Object key = it.next(); + Object value = it.getValue(); + if (value == null) { + if (map.get(key) != null || map.containsKey(key) == false) { + return false; + } + } else { + if (value.equals(map.get(key)) == false) { + return false; + } + } + } + } catch (ClassCastException ignored) { + return false; + } catch (NullPointerException ignored) { + return false; + } + return true; + } + + /** + * Gets the standard Map hashCode. + * + * @return the hash code defined in the Map interface + */ + public int hashCode() { + int total = 0; + Iterator it = createEntrySetIterator(); + while (it.hasNext()) { + total += it.next().hashCode(); + } + return total; + } + + /** + * Gets the map as a String. + * + * @return a string version of the map + */ + public String toString() { + if (size() == 0) { + return "{}"; + } + StringBuilder buf = new StringBuilder(32 * size()); + buf.append('{'); + + MapIterator it = mapIterator(); + boolean hasNext = it.hasNext(); + while (hasNext) { + Object key = it.next(); + Object value = it.getValue(); + buf.append(key == this ? "(this Map)" : key).append('=').append(value == this ? "(this Map)" : value); + + hasNext = it.hasNext(); + if (hasNext) { + buf.append(',').append(' '); + } + } + + buf.append('}'); + return buf.toString(); + } +} diff --git a/src/org/jivesoftware/smack/util/collections/AbstractKeyValue.java b/src/org/jivesoftware/smack/util/collections/AbstractKeyValue.java new file mode 100644 index 0000000..decc342 --- /dev/null +++ b/src/org/jivesoftware/smack/util/collections/AbstractKeyValue.java @@ -0,0 +1,80 @@ +// GenericsNote: Converted. +/* + * Copyright 2003-2004 The Apache Software Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.jivesoftware.smack.util.collections; + + +/** + * Abstract pair class to assist with creating KeyValue and MapEntry implementations. + * + * @author James Strachan + * @author Michael A. Smith + * @author Neil O'Toole + * @author Matt Hall, John Watkinson, Stephen Colebourne + * @version $Revision: 1.1 $ $Date: 2005/10/11 17:05:32 $ + * @since Commons Collections 3.0 + */ +public abstract class AbstractKeyValue <K,V> implements KeyValue<K, V> { + + /** + * The key + */ + protected K key; + /** + * The value + */ + protected V value; + + /** + * Constructs a new pair with the specified key and given value. + * + * @param key the key for the entry, may be null + * @param value the value for the entry, may be null + */ + protected AbstractKeyValue(K key, V value) { + super(); + this.key = key; + this.value = value; + } + + /** + * Gets the key from the pair. + * + * @return the key + */ + public K getKey() { + return key; + } + + /** + * Gets the value from the pair. + * + * @return the value + */ + public V getValue() { + return value; + } + + /** + * Gets a debugging String view of the pair. + * + * @return a String view of the entry + */ + public String toString() { + return new StringBuilder().append(getKey()).append('=').append(getValue()).toString(); + } + +} diff --git a/src/org/jivesoftware/smack/util/collections/AbstractMapEntry.java b/src/org/jivesoftware/smack/util/collections/AbstractMapEntry.java new file mode 100644 index 0000000..2feb308 --- /dev/null +++ b/src/org/jivesoftware/smack/util/collections/AbstractMapEntry.java @@ -0,0 +1,89 @@ +// GenericsNote: Converted. +/* + * Copyright 2003-2004 The Apache Software Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.jivesoftware.smack.util.collections; + +import java.util.Map; + +/** + * Abstract Pair class to assist with creating correct Map Entry implementations. + * + * @author James Strachan + * @author Michael A. Smith + * @author Neil O'Toole + * @author Matt Hall, John Watkinson, Stephen Colebourne + * @version $Revision: 1.1 $ $Date: 2005/10/11 17:05:32 $ + * @since Commons Collections 3.0 + */ +public abstract class AbstractMapEntry <K,V> extends AbstractKeyValue<K, V> implements Map.Entry<K, V> { + + /** + * Constructs a new entry with the given key and given value. + * + * @param key the key for the entry, may be null + * @param value the value for the entry, may be null + */ + protected AbstractMapEntry(K key, V value) { + super(key, value); + } + + // Map.Entry interface + //------------------------------------------------------------------------- + /** + * Sets the value stored in this Map Entry. + * <p/> + * This Map Entry is not connected to a Map, so only the local data is changed. + * + * @param value the new value + * @return the previous value + */ + public V setValue(V value) { + V answer = this.value; + this.value = value; + return answer; + } + + /** + * Compares this Map Entry with another Map Entry. + * <p/> + * Implemented per API documentation of {@link java.util.Map.Entry#equals(Object)} + * + * @param obj the object to compare to + * @return true if equal key and value + */ + public boolean equals(Object obj) { + if (obj == this) { + return true; + } + if (obj instanceof Map.Entry == false) { + return false; + } + Map.Entry other = (Map.Entry) obj; + return (getKey() == null ? other.getKey() == null : getKey().equals(other.getKey())) && (getValue() == null ? other.getValue() == null : getValue().equals(other.getValue())); + } + + /** + * Gets a hashCode compatible with the equals method. + * <p/> + * Implemented per API documentation of {@link java.util.Map.Entry#hashCode()} + * + * @return a suitable hash code + */ + public int hashCode() { + return (getKey() == null ? 0 : getKey().hashCode()) ^ (getValue() == null ? 0 : getValue().hashCode()); + } + +} diff --git a/src/org/jivesoftware/smack/util/collections/AbstractReferenceMap.java b/src/org/jivesoftware/smack/util/collections/AbstractReferenceMap.java new file mode 100644 index 0000000..b57f17d --- /dev/null +++ b/src/org/jivesoftware/smack/util/collections/AbstractReferenceMap.java @@ -0,0 +1,1025 @@ +// Converted, with some major refactors required. Not as memory-efficient as before, could use additional refactoring. +// Perhaps use four different types of HashEntry classes for max efficiency: +// normal HashEntry for HARD,HARD +// HardRefEntry for HARD,(SOFT|WEAK) +// RefHardEntry for (SOFT|WEAK),HARD +// RefRefEntry for (SOFT|WEAK),(SOFT|WEAK) +/* + * Copyright 2002-2004 The Apache Software Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.jivesoftware.smack.util.collections; + +import java.io.IOException; +import java.io.ObjectInputStream; +import java.io.ObjectOutputStream; +import java.lang.ref.Reference; +import java.lang.ref.ReferenceQueue; +import java.lang.ref.SoftReference; +import java.lang.ref.WeakReference; +import java.util.*; + +/** + * An abstract implementation of a hash-based map that allows the entries to + * be removed by the garbage collector. + * <p/> + * This class implements all the features necessary for a subclass reference + * hash-based map. Key-value entries are stored in instances of the + * <code>ReferenceEntry</code> class which can be overridden and replaced. + * The iterators can similarly be replaced, without the need to replace the KeySet, + * EntrySet and Values view classes. + * <p/> + * Overridable methods are provided to change the default hashing behaviour, and + * to change how entries are added to and removed from the map. Hopefully, all you + * need for unusual subclasses is here. + * <p/> + * When you construct an <code>AbstractReferenceMap</code>, you can specify what + * kind of references are used to store the map's keys and values. + * If non-hard references are used, then the garbage collector can remove + * mappings if a key or value becomes unreachable, or if the JVM's memory is + * running low. For information on how the different reference types behave, + * see {@link Reference}. + * <p/> + * Different types of references can be specified for keys and values. + * The keys can be configured to be weak but the values hard, + * in which case this class will behave like a + * <a href="http://java.sun.com/j2se/1.4/docs/api/java/util/WeakHashMap.html"> + * <code>WeakHashMap</code></a>. However, you can also specify hard keys and + * weak values, or any other combination. The default constructor uses + * hard keys and soft values, providing a memory-sensitive cache. + * <p/> + * This {@link Map} implementation does <i>not</i> allow null elements. + * Attempting to add a null key or value to the map will raise a + * <code>NullPointerException</code>. + * <p/> + * All the available iterators can be reset back to the start by casting to + * <code>ResettableIterator</code> and calling <code>reset()</code>. + * <p/> + * This implementation is not synchronized. + * You can use {@link java.util.Collections#synchronizedMap} to + * provide synchronized access to a <code>ReferenceMap</code>. + * + * @author Paul Jack + * @author Matt Hall, John Watkinson, Stephen Colebourne + * @version $Revision: 1.1 $ $Date: 2005/10/11 17:05:32 $ + * @see java.lang.ref.Reference + * @since Commons Collections 3.1 (extracted from ReferenceMap in 3.0) + */ +public abstract class AbstractReferenceMap <K,V> extends AbstractHashedMap<K, V> { + + /** + * Constant indicating that hard references should be used + */ + public static final int HARD = 0; + + /** + * Constant indicating that soft references should be used + */ + public static final int SOFT = 1; + + /** + * Constant indicating that weak references should be used + */ + public static final int WEAK = 2; + + /** + * The reference type for keys. Must be HARD, SOFT, WEAK. + * + * @serial + */ + protected int keyType; + + /** + * The reference type for values. Must be HARD, SOFT, WEAK. + * + * @serial + */ + protected int valueType; + + /** + * Should the value be automatically purged when the associated key has been collected? + */ + protected boolean purgeValues; + + /** + * ReferenceQueue used to eliminate stale mappings. + * See purge. + */ + private transient ReferenceQueue queue; + + //----------------------------------------------------------------------- + /** + * Constructor used during deserialization. + */ + protected AbstractReferenceMap() { + super(); + } + + /** + * Constructs a new empty map with the specified reference types, + * load factor and initial capacity. + * + * @param keyType the type of reference to use for keys; + * must be {@link #SOFT} or {@link #WEAK} + * @param valueType the type of reference to use for values; + * must be {@link #SOFT} or {@link #WEAK} + * @param capacity the initial capacity for the map + * @param loadFactor the load factor for the map + * @param purgeValues should the value be automatically purged when the + * key is garbage collected + */ + protected AbstractReferenceMap(int keyType, int valueType, int capacity, float loadFactor, boolean purgeValues) { + super(capacity, loadFactor); + verify("keyType", keyType); + verify("valueType", valueType); + this.keyType = keyType; + this.valueType = valueType; + this.purgeValues = purgeValues; + } + + /** + * Initialise this subclass during construction, cloning or deserialization. + */ + protected void init() { + queue = new ReferenceQueue(); + } + + //----------------------------------------------------------------------- + /** + * Checks the type int is a valid value. + * + * @param name the name for error messages + * @param type the type value to check + * @throws IllegalArgumentException if the value if invalid + */ + private static void verify(String name, int type) { + if ((type < HARD) || (type > WEAK)) { + throw new IllegalArgumentException(name + " must be HARD, SOFT, WEAK."); + } + } + + //----------------------------------------------------------------------- + /** + * Gets the size of the map. + * + * @return the size + */ + public int size() { + purgeBeforeRead(); + return super.size(); + } + + /** + * Checks whether the map is currently empty. + * + * @return true if the map is currently size zero + */ + public boolean isEmpty() { + purgeBeforeRead(); + return super.isEmpty(); + } + + /** + * Checks whether the map contains the specified key. + * + * @param key the key to search for + * @return true if the map contains the key + */ + public boolean containsKey(Object key) { + purgeBeforeRead(); + Entry entry = getEntry(key); + if (entry == null) { + return false; + } + return (entry.getValue() != null); + } + + /** + * Checks whether the map contains the specified value. + * + * @param value the value to search for + * @return true if the map contains the value + */ + public boolean containsValue(Object value) { + purgeBeforeRead(); + if (value == null) { + return false; + } + return super.containsValue(value); + } + + /** + * Gets the value mapped to the key specified. + * + * @param key the key + * @return the mapped value, null if no match + */ + public V get(Object key) { + purgeBeforeRead(); + Entry<K, V> entry = getEntry(key); + if (entry == null) { + return null; + } + return entry.getValue(); + } + + + /** + * Puts a key-value mapping into this map. + * Neither the key nor the value may be null. + * + * @param key the key to add, must not be null + * @param value the value to add, must not be null + * @return the value previously mapped to this key, null if none + * @throws NullPointerException if either the key or value is null + */ + public V put(K key, V value) { + if (key == null) { + throw new NullPointerException("null keys not allowed"); + } + if (value == null) { + throw new NullPointerException("null values not allowed"); + } + + purgeBeforeWrite(); + return super.put(key, value); + } + + /** + * Removes the specified mapping from this map. + * + * @param key the mapping to remove + * @return the value mapped to the removed key, null if key not in map + */ + public V remove(Object key) { + if (key == null) { + return null; + } + purgeBeforeWrite(); + return super.remove(key); + } + + /** + * Clears this map. + */ + public void clear() { + super.clear(); + while (queue.poll() != null) { + } // drain the queue + } + + //----------------------------------------------------------------------- + /** + * Gets a MapIterator over the reference map. + * The iterator only returns valid key/value pairs. + * + * @return a map iterator + */ + public MapIterator<K, V> mapIterator() { + return new ReferenceMapIterator<K, V>(this); + } + + /** + * Returns a set view of this map's entries. + * An iterator returned entry is valid until <code>next()</code> is called again. + * The <code>setValue()</code> method on the <code>toArray</code> entries has no effect. + * + * @return a set view of this map's entries + */ + public Set<Map.Entry<K, V>> entrySet() { + if (entrySet == null) { + entrySet = new ReferenceEntrySet<K, V>(this); + } + return entrySet; + } + + /** + * Returns a set view of this map's keys. + * + * @return a set view of this map's keys + */ + public Set<K> keySet() { + if (keySet == null) { + keySet = new ReferenceKeySet<K, V>(this); + } + return keySet; + } + + /** + * Returns a collection view of this map's values. + * + * @return a set view of this map's values + */ + public Collection<V> values() { + if (values == null) { + values = new ReferenceValues<K, V>(this); + } + return values; + } + + //----------------------------------------------------------------------- + /** + * Purges stale mappings from this map before read operations. + * <p/> + * This implementation calls {@link #purge()} to maintain a consistent state. + */ + protected void purgeBeforeRead() { + purge(); + } + + /** + * Purges stale mappings from this map before write operations. + * <p/> + * This implementation calls {@link #purge()} to maintain a consistent state. + */ + protected void purgeBeforeWrite() { + purge(); + } + + /** + * Purges stale mappings from this map. + * <p/> + * Note that this method is not synchronized! Special + * care must be taken if, for instance, you want stale + * mappings to be removed on a periodic basis by some + * background thread. + */ + protected void purge() { + Reference ref = queue.poll(); + while (ref != null) { + purge(ref); + ref = queue.poll(); + } + } + + /** + * Purges the specified reference. + * + * @param ref the reference to purge + */ + protected void purge(Reference ref) { + // The hashCode of the reference is the hashCode of the + // mapping key, even if the reference refers to the + // mapping value... + int hash = ref.hashCode(); + int index = hashIndex(hash, data.length); + HashEntry<K, V> previous = null; + HashEntry<K, V> entry = data[index]; + while (entry != null) { + if (((ReferenceEntry<K, V>) entry).purge(ref)) { + if (previous == null) { + data[index] = entry.next; + } else { + previous.next = entry.next; + } + this.size--; + return; + } + previous = entry; + entry = entry.next; + } + + } + + //----------------------------------------------------------------------- + /** + * Gets the entry mapped to the key specified. + * + * @param key the key + * @return the entry, null if no match + */ + protected HashEntry<K, V> getEntry(Object key) { + if (key == null) { + return null; + } else { + return super.getEntry(key); + } + } + + /** + * Gets the hash code for a MapEntry. + * Subclasses can override this, for example to use the identityHashCode. + * + * @param key the key to get a hash code for, may be null + * @param value the value to get a hash code for, may be null + * @return the hash code, as per the MapEntry specification + */ + protected int hashEntry(Object key, Object value) { + return (key == null ? 0 : key.hashCode()) ^ (value == null ? 0 : value.hashCode()); + } + + /** + * Compares two keys, in internal converted form, to see if they are equal. + * <p/> + * This implementation converts the key from the entry to a real reference + * before comparison. + * + * @param key1 the first key to compare passed in from outside + * @param key2 the second key extracted from the entry via <code>entry.key</code> + * @return true if equal + */ + protected boolean isEqualKey(Object key1, Object key2) { + //if ((key1 == null) && (key2 != null) || (key1 != null) || (key2 == null)) { + // return false; + //} + // GenericsNote: Conversion from reference handled by getKey() which replaced all .key references + //key2 = (keyType > HARD ? ((Reference) key2).get() : key2); + return (key1 == key2 || key1.equals(key2)); + } + + /** + * Creates a ReferenceEntry instead of a HashEntry. + * + * @param next the next entry in sequence + * @param hashCode the hash code to use + * @param key the key to store + * @param value the value to store + * @return the newly created entry + */ + public HashEntry<K, V> createEntry(HashEntry<K, V> next, int hashCode, K key, V value) { + return new ReferenceEntry<K, V>(this, (ReferenceEntry<K, V>) next, hashCode, key, value); + } + + /** + * Creates an entry set iterator. + * + * @return the entrySet iterator + */ + protected Iterator<Map.Entry<K, V>> createEntrySetIterator() { + return new ReferenceEntrySetIterator<K, V>(this); + } + + /** + * Creates an key set iterator. + * + * @return the keySet iterator + */ + protected Iterator<K> createKeySetIterator() { + return new ReferenceKeySetIterator<K, V>(this); + } + + /** + * Creates an values iterator. + * + * @return the values iterator + */ + protected Iterator<V> createValuesIterator() { + return new ReferenceValuesIterator<K, V>(this); + } + + //----------------------------------------------------------------------- + /** + * EntrySet implementation. + */ + static class ReferenceEntrySet <K,V> extends EntrySet<K, V> { + + protected ReferenceEntrySet(AbstractHashedMap<K, V> parent) { + super(parent); + } + + public Object[] toArray() { + return toArray(new Object[0]); + } + + public <T> T[] toArray(T[] arr) { + // special implementation to handle disappearing entries + ArrayList<Map.Entry<K, V>> list = new ArrayList<Map.Entry<K, V>>(); + Iterator<Map.Entry<K, V>> iterator = iterator(); + while (iterator.hasNext()) { + Map.Entry<K, V> e = iterator.next(); + list.add(new DefaultMapEntry<K, V>(e.getKey(), e.getValue())); + } + return list.toArray(arr); + } + } + + //----------------------------------------------------------------------- + /** + * KeySet implementation. + */ + static class ReferenceKeySet <K,V> extends KeySet<K, V> { + + protected ReferenceKeySet(AbstractHashedMap<K, V> parent) { + super(parent); + } + + public Object[] toArray() { + return toArray(new Object[0]); + } + + public <T> T[] toArray(T[] arr) { + // special implementation to handle disappearing keys + List<K> list = new ArrayList<K>(parent.size()); + for (Iterator<K> it = iterator(); it.hasNext();) { + list.add(it.next()); + } + return list.toArray(arr); + } + } + + //----------------------------------------------------------------------- + /** + * Values implementation. + */ + static class ReferenceValues <K,V> extends Values<K, V> { + + protected ReferenceValues(AbstractHashedMap<K, V> parent) { + super(parent); + } + + public Object[] toArray() { + return toArray(new Object[0]); + } + + public <T> T[] toArray(T[] arr) { + // special implementation to handle disappearing values + List<V> list = new ArrayList<V>(parent.size()); + for (Iterator<V> it = iterator(); it.hasNext();) { + list.add(it.next()); + } + return list.toArray(arr); + } + } + + //----------------------------------------------------------------------- + /** + * A MapEntry implementation for the map. + * <p/> + * If getKey() or getValue() returns null, it means + * the mapping is stale and should be removed. + * + * @since Commons Collections 3.1 + */ + protected static class ReferenceEntry <K,V> extends HashEntry<K, V> { + /** + * The parent map + */ + protected final AbstractReferenceMap<K, V> parent; + + protected Reference<K> refKey; + protected Reference<V> refValue; + + /** + * Creates a new entry object for the ReferenceMap. + * + * @param parent the parent map + * @param next the next entry in the hash bucket + * @param hashCode the hash code of the key + * @param key the key + * @param value the value + */ + public ReferenceEntry(AbstractReferenceMap<K, V> parent, ReferenceEntry<K, V> next, int hashCode, K key, V value) { + super(next, hashCode, null, null); + this.parent = parent; + if (parent.keyType != HARD) { + refKey = toReference(parent.keyType, key, hashCode); + } else { + this.setKey(key); + } + if (parent.valueType != HARD) { + refValue = toReference(parent.valueType, value, hashCode); // the key hashCode is passed in deliberately + } else { + this.setValue(value); + } + } + + /** + * Gets the key from the entry. + * This method dereferences weak and soft keys and thus may return null. + * + * @return the key, which may be null if it was garbage collected + */ + public K getKey() { + return (parent.keyType > HARD) ? refKey.get() : super.getKey(); + } + + /** + * Gets the value from the entry. + * This method dereferences weak and soft value and thus may return null. + * + * @return the value, which may be null if it was garbage collected + */ + public V getValue() { + return (parent.valueType > HARD) ? refValue.get() : super.getValue(); + } + + /** + * Sets the value of the entry. + * + * @param obj the object to store + * @return the previous value + */ + public V setValue(V obj) { + V old = getValue(); + if (parent.valueType > HARD) { + refValue.clear(); + refValue = toReference(parent.valueType, obj, hashCode); + } else { + super.setValue(obj); + } + return old; + } + + /** + * Compares this map entry to another. + * <p/> + * This implementation uses <code>isEqualKey</code> and + * <code>isEqualValue</code> on the main map for comparison. + * + * @param obj the other map entry to compare to + * @return true if equal, false if not + */ + public boolean equals(Object obj) { + if (obj == this) { + return true; + } + if (obj instanceof Map.Entry == false) { + return false; + } + + Map.Entry entry = (Map.Entry) obj; + Object entryKey = entry.getKey(); // convert to hard reference + Object entryValue = entry.getValue(); // convert to hard reference + if ((entryKey == null) || (entryValue == null)) { + return false; + } + // compare using map methods, aiding identity subclass + // note that key is direct access and value is via method + return parent.isEqualKey(entryKey, getKey()) && parent.isEqualValue(entryValue, getValue()); + } + + /** + * Gets the hashcode of the entry using temporary hard references. + * <p/> + * This implementation uses <code>hashEntry</code> on the main map. + * + * @return the hashcode of the entry + */ + public int hashCode() { + return parent.hashEntry(getKey(), getValue()); + } + + /** + * Constructs a reference of the given type to the given referent. + * The reference is registered with the queue for later purging. + * + * @param type HARD, SOFT or WEAK + * @param referent the object to refer to + * @param hash the hash code of the <i>key</i> of the mapping; + * this number might be different from referent.hashCode() if + * the referent represents a value and not a key + */ + protected <T> Reference<T> toReference(int type, T referent, int hash) { + switch (type) { + case SOFT: + return new SoftRef<T>(hash, referent, parent.queue); + case WEAK: + return new WeakRef<T>(hash, referent, parent.queue); + default: + throw new Error("Attempt to create hard reference in ReferenceMap!"); + } + } + + /** + * Purges the specified reference + * + * @param ref the reference to purge + * @return true or false + */ + boolean purge(Reference ref) { + boolean r = (parent.keyType > HARD) && (refKey == ref); + r = r || ((parent.valueType > HARD) && (refValue == ref)); + if (r) { + if (parent.keyType > HARD) { + refKey.clear(); + } + if (parent.valueType > HARD) { + refValue.clear(); + } else if (parent.purgeValues) { + setValue(null); + } + } + return r; + } + + /** + * Gets the next entry in the bucket. + * + * @return the next entry in the bucket + */ + protected ReferenceEntry<K, V> next() { + return (ReferenceEntry<K, V>) next; + } + } + + //----------------------------------------------------------------------- + /** + * The EntrySet iterator. + */ + static class ReferenceIteratorBase <K,V> { + /** + * The parent map + */ + final AbstractReferenceMap<K, V> parent; + + // These fields keep track of where we are in the table. + int index; + ReferenceEntry<K, V> entry; + ReferenceEntry<K, V> previous; + + // These Object fields provide hard references to the + // current and next entry; this assures that if hasNext() + // returns true, next() will actually return a valid element. + K nextKey; + V nextValue; + K currentKey; + V currentValue; + + int expectedModCount; + + public ReferenceIteratorBase(AbstractReferenceMap<K, V> parent) { + super(); + this.parent = parent; + index = (parent.size() != 0 ? parent.data.length : 0); + // have to do this here! size() invocation above + // may have altered the modCount. + expectedModCount = parent.modCount; + } + + public boolean hasNext() { + checkMod(); + while (nextNull()) { + ReferenceEntry<K, V> e = entry; + int i = index; + while ((e == null) && (i > 0)) { + i--; + e = (ReferenceEntry<K, V>) parent.data[i]; + } + entry = e; + index = i; + if (e == null) { + currentKey = null; + currentValue = null; + return false; + } + nextKey = e.getKey(); + nextValue = e.getValue(); + if (nextNull()) { + entry = entry.next(); + } + } + return true; + } + + private void checkMod() { + if (parent.modCount != expectedModCount) { + throw new ConcurrentModificationException(); + } + } + + private boolean nextNull() { + return (nextKey == null) || (nextValue == null); + } + + protected ReferenceEntry<K, V> nextEntry() { + checkMod(); + if (nextNull() && !hasNext()) { + throw new NoSuchElementException(); + } + previous = entry; + entry = entry.next(); + currentKey = nextKey; + currentValue = nextValue; + nextKey = null; + nextValue = null; + return previous; + } + + protected ReferenceEntry<K, V> currentEntry() { + checkMod(); + return previous; + } + + public ReferenceEntry<K, V> superNext() { + return nextEntry(); + } + + public void remove() { + checkMod(); + if (previous == null) { + throw new IllegalStateException(); + } + parent.remove(currentKey); + previous = null; + currentKey = null; + currentValue = null; + expectedModCount = parent.modCount; + } + } + + /** + * The EntrySet iterator. + */ + static class ReferenceEntrySetIterator <K,V> extends ReferenceIteratorBase<K, V> implements Iterator<Map.Entry<K, V>> { + + public ReferenceEntrySetIterator(AbstractReferenceMap<K, V> abstractReferenceMap) { + super(abstractReferenceMap); + } + + public ReferenceEntry<K, V> next() { + return superNext(); + } + + } + + /** + * The keySet iterator. + */ + static class ReferenceKeySetIterator <K,V> extends ReferenceIteratorBase<K, V> implements Iterator<K> { + + ReferenceKeySetIterator(AbstractReferenceMap<K, V> parent) { + super(parent); + } + + public K next() { + return nextEntry().getKey(); + } + } + + /** + * The values iterator. + */ + static class ReferenceValuesIterator <K,V> extends ReferenceIteratorBase<K, V> implements Iterator<V> { + + ReferenceValuesIterator(AbstractReferenceMap<K, V> parent) { + super(parent); + } + + public V next() { + return nextEntry().getValue(); + } + } + + /** + * The MapIterator implementation. + */ + static class ReferenceMapIterator <K,V> extends ReferenceIteratorBase<K, V> implements MapIterator<K, V> { + + protected ReferenceMapIterator(AbstractReferenceMap<K, V> parent) { + super(parent); + } + + public K next() { + return nextEntry().getKey(); + } + + public K getKey() { + HashEntry<K, V> current = currentEntry(); + if (current == null) { + throw new IllegalStateException(AbstractHashedMap.GETKEY_INVALID); + } + return current.getKey(); + } + + public V getValue() { + HashEntry<K, V> current = currentEntry(); + if (current == null) { + throw new IllegalStateException(AbstractHashedMap.GETVALUE_INVALID); + } + return current.getValue(); + } + + public V setValue(V value) { + HashEntry<K, V> current = currentEntry(); + if (current == null) { + throw new IllegalStateException(AbstractHashedMap.SETVALUE_INVALID); + } + return current.setValue(value); + } + } + + //----------------------------------------------------------------------- + // These two classes store the hashCode of the key of + // of the mapping, so that after they're dequeued a quick + // lookup of the bucket in the table can occur. + + /** + * A soft reference holder. + */ + static class SoftRef <T> extends SoftReference<T> { + /** + * the hashCode of the key (even if the reference points to a value) + */ + private int hash; + + public SoftRef(int hash, T r, ReferenceQueue q) { + super(r, q); + this.hash = hash; + } + + public int hashCode() { + return hash; + } + } + + /** + * A weak reference holder. + */ + static class WeakRef <T> extends WeakReference<T> { + /** + * the hashCode of the key (even if the reference points to a value) + */ + private int hash; + + public WeakRef(int hash, T r, ReferenceQueue q) { + super(r, q); + this.hash = hash; + } + + public int hashCode() { + return hash; + } + } + + //----------------------------------------------------------------------- + /** + * Replaces the superclass method to store the state of this class. + * <p/> + * Serialization is not one of the JDK's nicest topics. Normal serialization will + * initialise the superclass before the subclass. Sometimes however, this isn't + * what you want, as in this case the <code>put()</code> method on read can be + * affected by subclass state. + * <p/> + * The solution adopted here is to serialize the state data of this class in + * this protected method. This method must be called by the + * <code>writeObject()</code> of the first serializable subclass. + * <p/> + * Subclasses may override if they have a specific field that must be present + * on read before this implementation will work. Generally, the read determines + * what must be serialized here, if anything. + * + * @param out the output stream + */ + protected void doWriteObject(ObjectOutputStream out) throws IOException { + out.writeInt(keyType); + out.writeInt(valueType); + out.writeBoolean(purgeValues); + out.writeFloat(loadFactor); + out.writeInt(data.length); + for (MapIterator it = mapIterator(); it.hasNext();) { + out.writeObject(it.next()); + out.writeObject(it.getValue()); + } + out.writeObject(null); // null terminate map + // do not call super.doWriteObject() as code there doesn't work for reference map + } + + /** + * Replaces the superclassm method to read the state of this class. + * <p/> + * Serialization is not one of the JDK's nicest topics. Normal serialization will + * initialise the superclass before the subclass. Sometimes however, this isn't + * what you want, as in this case the <code>put()</code> method on read can be + * affected by subclass state. + * <p/> + * The solution adopted here is to deserialize the state data of this class in + * this protected method. This method must be called by the + * <code>readObject()</code> of the first serializable subclass. + * <p/> + * Subclasses may override if the subclass has a specific field that must be present + * before <code>put()</code> or <code>calculateThreshold()</code> will work correctly. + * + * @param in the input stream + */ + protected void doReadObject(ObjectInputStream in) throws IOException, ClassNotFoundException { + this.keyType = in.readInt(); + this.valueType = in.readInt(); + this.purgeValues = in.readBoolean(); + this.loadFactor = in.readFloat(); + int capacity = in.readInt(); + init(); + data = new HashEntry[capacity]; + while (true) { + K key = (K) in.readObject(); + if (key == null) { + break; + } + V value = (V) in.readObject(); + put(key, value); + } + threshold = calculateThreshold(data.length, loadFactor); + // do not call super.doReadObject() as code there doesn't work for reference map + } + +} diff --git a/src/org/jivesoftware/smack/util/collections/DefaultMapEntry.java b/src/org/jivesoftware/smack/util/collections/DefaultMapEntry.java new file mode 100644 index 0000000..ef752d0 --- /dev/null +++ b/src/org/jivesoftware/smack/util/collections/DefaultMapEntry.java @@ -0,0 +1,65 @@ +// GenericsNote: Converted. +/* + * Copyright 2001-2004 The Apache Software Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.jivesoftware.smack.util.collections; + + +import java.util.Map; + +/** + * A restricted implementation of {@link java.util.Map.Entry} that prevents + * the MapEntry contract from being broken. + * + * @author James Strachan + * @author Michael A. Smith + * @author Neil O'Toole + * @author Matt Hall, John Watkinson, Stephen Colebourne + * @version $Revision: 1.1 $ $Date: 2005/10/11 17:05:32 $ + * @since Commons Collections 3.0 + */ +public final class DefaultMapEntry <K,V> extends AbstractMapEntry<K, V> { + + /** + * Constructs a new entry with the specified key and given value. + * + * @param key the key for the entry, may be null + * @param value the value for the entry, may be null + */ + public DefaultMapEntry(final K key, final V value) { + super(key, value); + } + + /** + * Constructs a new entry from the specified KeyValue. + * + * @param pair the pair to copy, must not be null + * @throws NullPointerException if the entry is null + */ + public DefaultMapEntry(final KeyValue<K, V> pair) { + super(pair.getKey(), pair.getValue()); + } + + /** + * Constructs a new entry from the specified MapEntry. + * + * @param entry the entry to copy, must not be null + * @throws NullPointerException if the entry is null + */ + public DefaultMapEntry(final Map.Entry<K, V> entry) { + super(entry.getKey(), entry.getValue()); + } + +} diff --git a/src/org/jivesoftware/smack/util/collections/EmptyIterator.java b/src/org/jivesoftware/smack/util/collections/EmptyIterator.java new file mode 100644 index 0000000..6a8707f --- /dev/null +++ b/src/org/jivesoftware/smack/util/collections/EmptyIterator.java @@ -0,0 +1,58 @@ +// GenericsNote: Converted. +/* + * Copyright 2004 The Apache Software Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.jivesoftware.smack.util.collections; + +import java.util.Iterator; + +/** + * Provides an implementation of an empty iterator. + * <p/> + * This class provides an implementation of an empty iterator. + * This class provides for binary compatability between Commons Collections + * 2.1.1 and 3.1 due to issues with <code>IteratorUtils</code>. + * + * @author Matt Hall, John Watkinson, Stephen Colebourne + * @version $Revision: 1.1 $ $Date: 2005/10/11 17:05:24 $ + * @since Commons Collections 2.1.1 and 3.1 + */ +public class EmptyIterator <E> extends AbstractEmptyIterator<E> implements ResettableIterator<E> { + + /** + * Singleton instance of the iterator. + * + * @since Commons Collections 3.1 + */ + public static final ResettableIterator RESETTABLE_INSTANCE = new EmptyIterator(); + /** + * Singleton instance of the iterator. + * + * @since Commons Collections 2.1.1 and 3.1 + */ + public static final Iterator INSTANCE = RESETTABLE_INSTANCE; + + public static <T> Iterator<T> getInstance() { + return INSTANCE; + } + + /** + * Constructor. + */ + protected EmptyIterator() { + super(); + } + +} diff --git a/src/org/jivesoftware/smack/util/collections/EmptyMapIterator.java b/src/org/jivesoftware/smack/util/collections/EmptyMapIterator.java new file mode 100644 index 0000000..013f5ed --- /dev/null +++ b/src/org/jivesoftware/smack/util/collections/EmptyMapIterator.java @@ -0,0 +1,42 @@ +// GenericsNote: Converted. +/* + * Copyright 2004 The Apache Software Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.jivesoftware.smack.util.collections; + +/** + * Provides an implementation of an empty map iterator. + * + * @author Matt Hall, John Watkinson, Stephen Colebourne + * @version $Revision: 1.1 $ $Date: 2005/10/11 17:05:24 $ + * @since Commons Collections 3.1 + */ +public class EmptyMapIterator extends AbstractEmptyIterator implements MapIterator, ResettableIterator { + + /** + * Singleton instance of the iterator. + * + * @since Commons Collections 3.1 + */ + public static final MapIterator INSTANCE = new EmptyMapIterator(); + + /** + * Constructor. + */ + protected EmptyMapIterator() { + super(); + } + +} diff --git a/src/org/jivesoftware/smack/util/collections/IterableMap.java b/src/org/jivesoftware/smack/util/collections/IterableMap.java new file mode 100644 index 0000000..251b587 --- /dev/null +++ b/src/org/jivesoftware/smack/util/collections/IterableMap.java @@ -0,0 +1,61 @@ +// GenericsNote: Converted. +/* + * Copyright 2003-2004 The Apache Software Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.jivesoftware.smack.util.collections; + +import java.util.Map; + +/** + * Defines a map that can be iterated directly without needing to create an entry set. + * <p/> + * A map iterator is an efficient way of iterating over maps. + * There is no need to access the entry set or cast to Map Entry objects. + * <pre> + * IterableMap map = new HashedMap(); + * MapIterator it = map.mapIterator(); + * while (it.hasNext()) { + * Object key = it.next(); + * Object value = it.getValue(); + * it.setValue("newValue"); + * } + * </pre> + * + * @author Matt Hall, John Watkinson, Stephen Colebourne + * @version $Revision: 1.1 $ $Date: 2005/10/11 17:05:19 $ + * @since Commons Collections 3.0 + */ +public interface IterableMap <K,V> extends Map<K, V> { + + /** + * Obtains a <code>MapIterator</code> over the map. + * <p/> + * A map iterator is an efficient way of iterating over maps. + * There is no need to access the entry set or cast to Map Entry objects. + * <pre> + * IterableMap map = new HashedMap(); + * MapIterator it = map.mapIterator(); + * while (it.hasNext()) { + * Object key = it.next(); + * Object value = it.getValue(); + * it.setValue("newValue"); + * } + * </pre> + * + * @return a map iterator + */ + MapIterator<K, V> mapIterator(); + +} diff --git a/src/org/jivesoftware/smack/util/collections/KeyValue.java b/src/org/jivesoftware/smack/util/collections/KeyValue.java new file mode 100644 index 0000000..c73621d --- /dev/null +++ b/src/org/jivesoftware/smack/util/collections/KeyValue.java @@ -0,0 +1,46 @@ +// GenericsNote: Converted. +/* + * Copyright 2003-2004 The Apache Software Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.jivesoftware.smack.util.collections; + +/** + * Defines a simple key value pair. + * <p/> + * A Map Entry has considerable additional semantics over and above a simple + * key-value pair. This interface defines the minimum key value, with just the + * two get methods. + * + * @author Matt Hall, John Watkinson, Stephen Colebourne + * @version $Revision: 1.1 $ $Date: 2005/10/11 17:05:19 $ + * @since Commons Collections 3.0 + */ +public interface KeyValue <K,V> { + + /** + * Gets the key from the pair. + * + * @return the key + */ + K getKey(); + + /** + * Gets the value from the pair. + * + * @return the value + */ + V getValue(); + +} diff --git a/src/org/jivesoftware/smack/util/collections/MapIterator.java b/src/org/jivesoftware/smack/util/collections/MapIterator.java new file mode 100644 index 0000000..fe2398c --- /dev/null +++ b/src/org/jivesoftware/smack/util/collections/MapIterator.java @@ -0,0 +1,109 @@ +// GenericsNote: Converted. +/* + * Copyright 2003-2004 The Apache Software Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.jivesoftware.smack.util.collections; + +import java.util.Iterator; + +/** + * Defines an iterator that operates over a <code>Map</code>. + * <p/> + * This iterator is a special version designed for maps. It can be more + * efficient to use this rather than an entry set iterator where the option + * is available, and it is certainly more convenient. + * <p/> + * A map that provides this interface may not hold the data internally using + * Map Entry objects, thus this interface can avoid lots of object creation. + * <p/> + * In use, this iterator iterates through the keys in the map. After each call + * to <code>next()</code>, the <code>getValue()</code> method provides direct + * access to the value. The value can also be set using <code>setValue()</code>. + * <pre> + * MapIterator it = map.mapIterator(); + * while (it.hasNext()) { + * Object key = it.next(); + * Object value = it.getValue(); + * it.setValue(newValue); + * } + * </pre> + * + * @author Matt Hall, John Watkinson, Stephen Colebourne + * @version $Revision: 1.1 $ $Date: 2005/10/11 17:05:19 $ + * @since Commons Collections 3.0 + */ +public interface MapIterator <K,V> extends Iterator<K> { + + /** + * Checks to see if there are more entries still to be iterated. + * + * @return <code>true</code> if the iterator has more elements + */ + boolean hasNext(); + + /** + * Gets the next <em>key</em> from the <code>Map</code>. + * + * @return the next key in the iteration + * @throws java.util.NoSuchElementException + * if the iteration is finished + */ + K next(); + + //----------------------------------------------------------------------- + /** + * Gets the current key, which is the key returned by the last call + * to <code>next()</code>. + * + * @return the current key + * @throws IllegalStateException if <code>next()</code> has not yet been called + */ + K getKey(); + + /** + * Gets the current value, which is the value associated with the last key + * returned by <code>next()</code>. + * + * @return the current value + * @throws IllegalStateException if <code>next()</code> has not yet been called + */ + V getValue(); + + //----------------------------------------------------------------------- + /** + * Removes the last returned key from the underlying <code>Map</code> (optional operation). + * <p/> + * This method can be called once per call to <code>next()</code>. + * + * @throws UnsupportedOperationException if remove is not supported by the map + * @throws IllegalStateException if <code>next()</code> has not yet been called + * @throws IllegalStateException if <code>remove()</code> has already been called + * since the last call to <code>next()</code> + */ + void remove(); + + /** + * Sets the value associated with the current key (optional operation). + * + * @param value the new value + * @return the previous value + * @throws UnsupportedOperationException if setValue is not supported by the map + * @throws IllegalStateException if <code>next()</code> has not yet been called + * @throws IllegalStateException if <code>remove()</code> has been called since the + * last call to <code>next()</code> + */ + V setValue(V value); + +} diff --git a/src/org/jivesoftware/smack/util/collections/ReferenceMap.java b/src/org/jivesoftware/smack/util/collections/ReferenceMap.java new file mode 100644 index 0000000..f30954d --- /dev/null +++ b/src/org/jivesoftware/smack/util/collections/ReferenceMap.java @@ -0,0 +1,161 @@ +// GenericsNote: Converted. +/* + * Copyright 2002-2004 The Apache Software Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.jivesoftware.smack.util.collections; + +import java.io.IOException; +import java.io.ObjectInputStream; +import java.io.ObjectOutputStream; +import java.io.Serializable; + +/** + * A <code>Map</code> implementation that allows mappings to be + * removed by the garbage collector. + * <p/> + * When you construct a <code>ReferenceMap</code>, you can specify what kind + * of references are used to store the map's keys and values. + * If non-hard references are used, then the garbage collector can remove + * mappings if a key or value becomes unreachable, or if the JVM's memory is + * running low. For information on how the different reference types behave, + * see {@link java.lang.ref.Reference}. + * <p/> + * Different types of references can be specified for keys and values. + * The keys can be configured to be weak but the values hard, + * in which case this class will behave like a + * <a href="http://java.sun.com/j2se/1.4/docs/api/java/util/WeakHashMap.html"> + * <code>WeakHashMap</code></a>. However, you can also specify hard keys and + * weak values, or any other combination. The default constructor uses + * hard keys and soft values, providing a memory-sensitive cache. + * <p/> + * This map is similar to ReferenceIdentityMap. + * It differs in that keys and values in this class are compared using <code>equals()</code>. + * <p/> + * This {@link java.util.Map} implementation does <i>not</i> allow null elements. + * Attempting to add a null key or value to the map will raise a <code>NullPointerException</code>. + * <p/> + * This implementation is not synchronized. + * You can use {@link java.util.Collections#synchronizedMap} to + * provide synchronized access to a <code>ReferenceMap</code>. + * Remember that synchronization will not stop the garbage collecter removing entries. + * <p/> + * All the available iterators can be reset back to the start by casting to + * <code>ResettableIterator</code> and calling <code>reset()</code>. + * <p/> + * NOTE: As from Commons Collections 3.1 this map extends <code>AbstractReferenceMap</code> + * (previously it extended AbstractMap). As a result, the implementation is now + * extensible and provides a <code>MapIterator</code>. + * + * @author Paul Jack + * @author Matt Hall, John Watkinson, Stephen Colebourne + * @version $Revision: 1.1 $ $Date: 2005/10/11 17:05:32 $ + * @see java.lang.ref.Reference + * @since Commons Collections 3.0 (previously in main package v2.1) + */ +public class ReferenceMap <K,V> extends AbstractReferenceMap<K, V> implements Serializable { + + /** + * Serialization version + */ + private static final long serialVersionUID = 1555089888138299607L; + + /** + * Constructs a new <code>ReferenceMap</code> that will + * use hard references to keys and soft references to values. + */ + public ReferenceMap() { + super(HARD, SOFT, DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR, false); + } + + /** + * Constructs a new <code>ReferenceMap</code> that will + * use the specified types of references. + * + * @param keyType the type of reference to use for keys; + * must be {@link #HARD}, {@link #SOFT}, {@link #WEAK} + * @param valueType the type of reference to use for values; + * must be {@link #HARD}, {@link #SOFT}, {@link #WEAK} + */ + public ReferenceMap(int keyType, int valueType) { + super(keyType, valueType, DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR, false); + } + + /** + * Constructs a new <code>ReferenceMap</code> that will + * use the specified types of references. + * + * @param keyType the type of reference to use for keys; + * must be {@link #HARD}, {@link #SOFT}, {@link #WEAK} + * @param valueType the type of reference to use for values; + * must be {@link #HARD}, {@link #SOFT}, {@link #WEAK} + * @param purgeValues should the value be automatically purged when the + * key is garbage collected + */ + public ReferenceMap(int keyType, int valueType, boolean purgeValues) { + super(keyType, valueType, DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR, purgeValues); + } + + /** + * Constructs a new <code>ReferenceMap</code> with the + * specified reference types, load factor and initial + * capacity. + * + * @param keyType the type of reference to use for keys; + * must be {@link #HARD}, {@link #SOFT}, {@link #WEAK} + * @param valueType the type of reference to use for values; + * must be {@link #HARD}, {@link #SOFT}, {@link #WEAK} + * @param capacity the initial capacity for the map + * @param loadFactor the load factor for the map + */ + public ReferenceMap(int keyType, int valueType, int capacity, float loadFactor) { + super(keyType, valueType, capacity, loadFactor, false); + } + + /** + * Constructs a new <code>ReferenceMap</code> with the + * specified reference types, load factor and initial + * capacity. + * + * @param keyType the type of reference to use for keys; + * must be {@link #HARD}, {@link #SOFT}, {@link #WEAK} + * @param valueType the type of reference to use for values; + * must be {@link #HARD}, {@link #SOFT}, {@link #WEAK} + * @param capacity the initial capacity for the map + * @param loadFactor the load factor for the map + * @param purgeValues should the value be automatically purged when the + * key is garbage collected + */ + public ReferenceMap(int keyType, int valueType, int capacity, float loadFactor, boolean purgeValues) { + super(keyType, valueType, capacity, loadFactor, purgeValues); + } + + //----------------------------------------------------------------------- + /** + * Write the map out using a custom routine. + */ + private void writeObject(ObjectOutputStream out) throws IOException { + out.defaultWriteObject(); + doWriteObject(out); + } + + /** + * Read the map in using a custom routine. + */ + private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException { + in.defaultReadObject(); + doReadObject(in); + } + +} diff --git a/src/org/jivesoftware/smack/util/collections/ResettableIterator.java b/src/org/jivesoftware/smack/util/collections/ResettableIterator.java new file mode 100644 index 0000000..cf814f7 --- /dev/null +++ b/src/org/jivesoftware/smack/util/collections/ResettableIterator.java @@ -0,0 +1,38 @@ +// GenericsNote: Converted. +/* + * Copyright 2003-2004 The Apache Software Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.jivesoftware.smack.util.collections; + +import java.util.Iterator; + +/** + * Defines an iterator that can be reset back to an initial state. + * <p/> + * This interface allows an iterator to be repeatedly reused. + * + * @author Matt Hall, John Watkinson, Stephen Colebourne + * @version $Revision: 1.1 $ $Date: 2005/10/11 17:05:19 $ + * @since Commons Collections 3.0 + */ +public interface ResettableIterator <E> extends Iterator<E> { + + /** + * Resets the iterator back to the position at which the iterator + * was created. + */ + public void reset(); + +} |