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+package org.apache.velocity.util;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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.
+ */
+
+/**
+ * Simple object pool. Based on ThreadPool and few other classes
+ *
+ * The pool will ignore overflow and return null if empty.
+ *
+ * @author Gal Shachor
+ * @author Costin
+ * @author <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a>
+ * @version $Id$
+ */
+public final class SimplePool
+{
+ /*
+ * Where the objects are held.
+ */
+ private Object pool[];
+
+ /**
+ * max amount of objects to be managed
+ * set via CTOR
+ */
+ private int max;
+
+ /**
+ * index of previous to next
+ * free slot
+ */
+ private int current=-1;
+
+ /**
+ * @param max
+ */
+ public SimplePool(int max)
+ {
+ this.max = max;
+ pool = new Object[max];
+ }
+
+ /**
+ * Add the object to the pool, silent nothing if the pool is full
+ * @param o
+ */
+ public void put(Object o)
+ {
+ int idx=-1;
+
+ synchronized(this)
+ {
+ /*
+ * if we aren't full
+ */
+
+ if (current < max - 1)
+ {
+ /*
+ * then increment the
+ * current index.
+ */
+ idx = ++current;
+ }
+
+ if (idx >= 0)
+ {
+ pool[idx] = o;
+ }
+ }
+ }
+
+ /**
+ * Get an object from the pool, null if the pool is empty.
+ * @return The object from the pool.
+ */
+ public Object get()
+ {
+ synchronized(this)
+ {
+ /*
+ * if we have any in the pool
+ */
+ if( current >= 0 )
+ {
+ /*
+ * remove the current one
+ */
+
+ Object o = pool[current];
+ pool[current] = null;
+
+ current--;
+
+ return o;
+ }
+ }
+
+ return null;
+ }
+
+ /**
+ * Return the size of the pool
+ * @return The pool size.
+ */
+ public int getMax()
+ {
+ return max;
+ }
+
+ /**
+ * for testing purposes, so we can examine the pool
+ *
+ * @return Array of Objects in the pool.
+ */
+ Object[] getPool()
+ {
+ return pool;
+ }
+}