diff options
Diffstat (limited to 'core/src/test/java/com/android/volley/toolbox/DiskBasedCacheTest.java')
-rw-r--r-- | core/src/test/java/com/android/volley/toolbox/DiskBasedCacheTest.java | 646 |
1 files changed, 646 insertions, 0 deletions
diff --git a/core/src/test/java/com/android/volley/toolbox/DiskBasedCacheTest.java b/core/src/test/java/com/android/volley/toolbox/DiskBasedCacheTest.java new file mode 100644 index 0000000..db6e491 --- /dev/null +++ b/core/src/test/java/com/android/volley/toolbox/DiskBasedCacheTest.java @@ -0,0 +1,646 @@ +/* + * Copyright (C) 2013 The Android Open Source Project + * + * 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 com.android.volley.toolbox; + +import static org.hamcrest.Matchers.arrayWithSize; +import static org.hamcrest.Matchers.emptyArray; +import static org.hamcrest.Matchers.equalTo; +import static org.hamcrest.Matchers.is; +import static org.hamcrest.Matchers.nullValue; +import static org.junit.Assert.assertEquals; +import static org.junit.Assert.assertNotNull; +import static org.junit.Assert.assertThat; +import static org.mockito.ArgumentMatchers.any; +import static org.mockito.ArgumentMatchers.anyInt; +import static org.mockito.Mockito.atLeastOnce; +import static org.mockito.Mockito.doReturn; +import static org.mockito.Mockito.doThrow; +import static org.mockito.Mockito.spy; +import static org.mockito.Mockito.verify; + +import com.android.volley.Cache; +import com.android.volley.Header; +import com.android.volley.toolbox.DiskBasedCache.CacheHeader; +import com.android.volley.toolbox.DiskBasedCache.CountingInputStream; +import java.io.ByteArrayInputStream; +import java.io.ByteArrayOutputStream; +import java.io.EOFException; +import java.io.File; +import java.io.FileOutputStream; +import java.io.IOException; +import java.io.InputStream; +import java.io.OutputStream; +import java.util.ArrayList; +import java.util.HashMap; +import java.util.List; +import java.util.Random; +import org.junit.After; +import org.junit.Before; +import org.junit.Rule; +import org.junit.Test; +import org.junit.rules.ExpectedException; +import org.junit.rules.TemporaryFolder; +import org.junit.runner.RunWith; +import org.robolectric.RobolectricTestRunner; +import org.robolectric.annotation.Config; + +@RunWith(RobolectricTestRunner.class) +@Config(sdk = 16) +public class DiskBasedCacheTest { + + private static final int MAX_SIZE = 1024 * 1024; + + private Cache cache; + + @Rule public TemporaryFolder temporaryFolder = new TemporaryFolder(); + + @Rule public ExpectedException exception = ExpectedException.none(); + + @Before + public void setup() throws IOException { + // Initialize empty cache + cache = new DiskBasedCache(temporaryFolder.getRoot(), MAX_SIZE); + cache.initialize(); + } + + @After + public void teardown() { + cache = null; + } + + @Test + public void testEmptyInitialize() { + assertThat(cache.get("key"), is(nullValue())); + } + + @Test + public void testPutGetZeroBytes() { + Cache.Entry entry = new Cache.Entry(); + entry.data = new byte[0]; + entry.serverDate = 1234567L; + entry.lastModified = 13572468L; + entry.ttl = 9876543L; + entry.softTtl = 8765432L; + entry.etag = "etag"; + entry.responseHeaders = new HashMap<>(); + entry.responseHeaders.put("fruit", "banana"); + entry.responseHeaders.put("color", "yellow"); + cache.put("my-magical-key", entry); + + assertThatEntriesAreEqual(cache.get("my-magical-key"), entry); + assertThat(cache.get("unknown-key"), is(nullValue())); + } + + @Test + public void testPutRemoveGet() { + Cache.Entry entry = randomData(511); + cache.put("key", entry); + + assertThatEntriesAreEqual(cache.get("key"), entry); + + cache.remove("key"); + assertThat(cache.get("key"), is(nullValue())); + assertThat(listCachedFiles(), is(emptyArray())); + } + + @Test + public void testPutClearGet() { + Cache.Entry entry = randomData(511); + cache.put("key", entry); + + assertThatEntriesAreEqual(cache.get("key"), entry); + + cache.clear(); + assertThat(cache.get("key"), is(nullValue())); + assertThat(listCachedFiles(), is(emptyArray())); + } + + @Test + public void testReinitialize() { + Cache.Entry entry = randomData(1023); + cache.put("key", entry); + + Cache copy = new DiskBasedCache(temporaryFolder.getRoot(), MAX_SIZE); + copy.initialize(); + + assertThatEntriesAreEqual(copy.get("key"), entry); + } + + @Test + public void testInvalidate() { + Cache.Entry entry = randomData(32); + entry.softTtl = 8765432L; + entry.ttl = 9876543L; + cache.put("key", entry); + + cache.invalidate("key", false); + entry.softTtl = 0; // expired + assertThatEntriesAreEqual(cache.get("key"), entry); + } + + @Test + public void testInvalidateFullExpire() { + Cache.Entry entry = randomData(32); + entry.softTtl = 8765432L; + entry.ttl = 9876543L; + cache.put("key", entry); + + cache.invalidate("key", true); + entry.softTtl = 0; // expired + entry.ttl = 0; // expired + assertThatEntriesAreEqual(cache.get("key"), entry); + } + + @Test + public void testTooLargeEntry() { + Cache.Entry entry = randomData(MAX_SIZE - getEntrySizeOnDisk("oversize")); + cache.put("oversize", entry); + + assertThat(cache.get("oversize"), is(nullValue())); + } + + @Test + public void testMaxSizeEntry() { + Cache.Entry entry = randomData(MAX_SIZE - getEntrySizeOnDisk("maxsize") - 1); + cache.put("maxsize", entry); + + assertThatEntriesAreEqual(cache.get("maxsize"), entry); + } + + @Test + public void testTrimAtThreshold() { + // Start with the largest possible entry. + Cache.Entry entry = randomData(MAX_SIZE - getEntrySizeOnDisk("maxsize") - 1); + cache.put("maxsize", entry); + + assertThatEntriesAreEqual(cache.get("maxsize"), entry); + + // Now any new entry should cause the first one to be cleared. + entry = randomData(0); + cache.put("bit", entry); + + assertThat(cache.get("goodsize"), is(nullValue())); + assertThatEntriesAreEqual(cache.get("bit"), entry); + } + + @Test + public void testTrimWithMultipleEvictions_underHysteresisThreshold() { + Cache.Entry entry1 = randomData(MAX_SIZE / 3 - getEntrySizeOnDisk("entry1") - 1); + cache.put("entry1", entry1); + Cache.Entry entry2 = randomData(MAX_SIZE / 3 - getEntrySizeOnDisk("entry2") - 1); + cache.put("entry2", entry2); + Cache.Entry entry3 = randomData(MAX_SIZE / 3 - getEntrySizeOnDisk("entry3") - 1); + cache.put("entry3", entry3); + + assertThatEntriesAreEqual(cache.get("entry1"), entry1); + assertThatEntriesAreEqual(cache.get("entry2"), entry2); + assertThatEntriesAreEqual(cache.get("entry3"), entry3); + + Cache.Entry entry = + randomData( + (int) (DiskBasedCache.HYSTERESIS_FACTOR * MAX_SIZE) + - getEntrySizeOnDisk("max")); + cache.put("max", entry); + + assertThat(cache.get("entry1"), is(nullValue())); + assertThat(cache.get("entry2"), is(nullValue())); + assertThat(cache.get("entry3"), is(nullValue())); + assertThatEntriesAreEqual(cache.get("max"), entry); + } + + @Test + public void testTrimWithMultipleEvictions_atHysteresisThreshold() { + Cache.Entry entry1 = randomData(MAX_SIZE / 3 - getEntrySizeOnDisk("entry1") - 1); + cache.put("entry1", entry1); + Cache.Entry entry2 = randomData(MAX_SIZE / 3 - getEntrySizeOnDisk("entry2") - 1); + cache.put("entry2", entry2); + Cache.Entry entry3 = randomData(MAX_SIZE / 3 - getEntrySizeOnDisk("entry3") - 1); + cache.put("entry3", entry3); + + assertThatEntriesAreEqual(cache.get("entry1"), entry1); + assertThatEntriesAreEqual(cache.get("entry2"), entry2); + assertThatEntriesAreEqual(cache.get("entry3"), entry3); + + Cache.Entry entry = + randomData( + (int) (DiskBasedCache.HYSTERESIS_FACTOR * MAX_SIZE) + - getEntrySizeOnDisk("max") + + 1); + cache.put("max", entry); + + assertThat(cache.get("entry1"), is(nullValue())); + assertThat(cache.get("entry2"), is(nullValue())); + assertThat(cache.get("entry3"), is(nullValue())); + assertThat(cache.get("max"), is(nullValue())); + } + + @Test + public void testTrimWithPartialEvictions() { + Cache.Entry entry1 = randomData(MAX_SIZE / 3 - getEntrySizeOnDisk("entry1") - 1); + cache.put("entry1", entry1); + Cache.Entry entry2 = randomData(MAX_SIZE / 3 - getEntrySizeOnDisk("entry2") - 1); + cache.put("entry2", entry2); + Cache.Entry entry3 = randomData(MAX_SIZE / 3 - getEntrySizeOnDisk("entry3") - 1); + cache.put("entry3", entry3); + + assertThatEntriesAreEqual(cache.get("entry1"), entry1); + assertThatEntriesAreEqual(cache.get("entry2"), entry2); + assertThatEntriesAreEqual(cache.get("entry3"), entry3); + + Cache.Entry entry4 = randomData((MAX_SIZE - getEntrySizeOnDisk("entry4") - 1) / 2); + cache.put("entry4", entry4); + + assertThat(cache.get("entry1"), is(nullValue())); + assertThat(cache.get("entry2"), is(nullValue())); + assertThatEntriesAreEqual(cache.get("entry3"), entry3); + assertThatEntriesAreEqual(cache.get("entry4"), entry4); + } + + @Test + public void testLargeEntryDoesntClearCache() { + // Writing a large entry to an empty cache should succeed + Cache.Entry largeEntry = randomData(MAX_SIZE - getEntrySizeOnDisk("largeEntry") - 1); + cache.put("largeEntry", largeEntry); + + assertThatEntriesAreEqual(cache.get("largeEntry"), largeEntry); + + // Reset and fill up ~half the cache. + cache.clear(); + Cache.Entry entry = randomData(MAX_SIZE / 2 - getEntrySizeOnDisk("entry") - 1); + cache.put("entry", entry); + + assertThatEntriesAreEqual(cache.get("entry"), entry); + + // Writing the large entry should no-op, because otherwise the pruning algorithm would clear + // the whole cache, since the large entry is above the hysteresis threshold. + cache.put("largeEntry", largeEntry); + + assertThat(cache.get("largeEntry"), is(nullValue())); + assertThatEntriesAreEqual(cache.get("entry"), entry); + } + + @Test + @SuppressWarnings("TryFinallyCanBeTryWithResources") + public void testGetBadMagic() throws IOException { + // Cache something + Cache.Entry entry = randomData(1023); + cache.put("key", entry); + assertThatEntriesAreEqual(cache.get("key"), entry); + + // Overwrite the magic header + File cacheFolder = temporaryFolder.getRoot(); + File file = cacheFolder.listFiles()[0]; + FileOutputStream fos = new FileOutputStream(file); + try { + DiskBasedCache.writeInt(fos, 0); // overwrite magic + } finally { + //noinspection ThrowFromFinallyBlock + fos.close(); + } + + assertThat(cache.get("key"), is(nullValue())); + assertThat(listCachedFiles(), is(emptyArray())); + } + + @Test + @SuppressWarnings("TryFinallyCanBeTryWithResources") + public void testGetWrongKey() throws IOException { + // Cache something + Cache.Entry entry = randomData(1023); + cache.put("key", entry); + assertThatEntriesAreEqual(cache.get("key"), entry); + + // Access the cached file + File cacheFolder = temporaryFolder.getRoot(); + File file = cacheFolder.listFiles()[0]; + FileOutputStream fos = new FileOutputStream(file); + try { + // Overwrite with a different key + CacheHeader wrongHeader = new CacheHeader("bad", entry); + wrongHeader.writeHeader(fos); + } finally { + //noinspection ThrowFromFinallyBlock + fos.close(); + } + + // key is gone, but file is still there + assertThat(cache.get("key"), is(nullValue())); + assertThat(listCachedFiles(), is(arrayWithSize(1))); + + // Note: file is now a zombie because its key does not map to its name + } + + @Test + public void testStreamToBytesNegativeLength() throws IOException { + byte[] data = new byte[1]; + CountingInputStream cis = + new CountingInputStream(new ByteArrayInputStream(data), data.length); + exception.expect(IOException.class); + DiskBasedCache.streamToBytes(cis, -1); + } + + @Test + public void testStreamToBytesExcessiveLength() throws IOException { + byte[] data = new byte[1]; + CountingInputStream cis = + new CountingInputStream(new ByteArrayInputStream(data), data.length); + exception.expect(IOException.class); + DiskBasedCache.streamToBytes(cis, 2); + } + + @Test + public void testStreamToBytesOverflow() throws IOException { + byte[] data = new byte[0]; + CountingInputStream cis = + new CountingInputStream(new ByteArrayInputStream(data), 0x100000000L); + exception.expect(IOException.class); + DiskBasedCache.streamToBytes(cis, 0x100000000L); // int value is 0 + } + + @Test + public void testReadHeaderListWithNegativeSize() throws IOException { + // If a cached header list is corrupted and begins with a negative size, + // verify that readHeaderList will throw an IOException. + ByteArrayOutputStream baos = new ByteArrayOutputStream(); + DiskBasedCache.writeInt(baos, -1); // negative size + CountingInputStream cis = + new CountingInputStream( + new ByteArrayInputStream(baos.toByteArray()), Integer.MAX_VALUE); + // Expect IOException due to negative size + exception.expect(IOException.class); + DiskBasedCache.readHeaderList(cis); + } + + @Test + public void testReadHeaderListWithGinormousSize() throws IOException { + // If a cached header list is corrupted and begins with 2GB size, verify + // that readHeaderList will throw EOFException rather than OutOfMemoryError. + ByteArrayOutputStream baos = new ByteArrayOutputStream(); + DiskBasedCache.writeInt(baos, Integer.MAX_VALUE); // 2GB size + CountingInputStream cis = + new CountingInputStream(new ByteArrayInputStream(baos.toByteArray()), baos.size()); + // Expect EOFException when end of stream is reached + exception.expect(EOFException.class); + DiskBasedCache.readHeaderList(cis); + } + + @Test + public void testFileIsDeletedWhenWriteHeaderFails() throws IOException { + // Create DataOutputStream that throws IOException + OutputStream mockedOutputStream = spy(OutputStream.class); + doThrow(IOException.class).when(mockedOutputStream).write(anyInt()); + + // Create read-only copy that fails to write anything + DiskBasedCache readonly = spy((DiskBasedCache) cache); + doReturn(mockedOutputStream).when(readonly).createOutputStream(any(File.class)); + + // Attempt to write + readonly.put("key", randomData(1111)); + + // write is called at least once because each linked stream flushes when closed + verify(mockedOutputStream, atLeastOnce()).write(anyInt()); + assertThat(readonly.get("key"), is(nullValue())); + assertThat(listCachedFiles(), is(emptyArray())); + + // Note: original cache will try (without success) to read from file + assertThat(cache.get("key"), is(nullValue())); + } + + @Test + public void testIOExceptionInInitialize() throws IOException { + // Cache a few kilobytes + cache.put("kilobyte", randomData(1024)); + cache.put("kilobyte2", randomData(1024)); + cache.put("kilobyte3", randomData(1024)); + + // Create DataInputStream that throws IOException + InputStream mockedInputStream = spy(InputStream.class); + //noinspection ResultOfMethodCallIgnored + doThrow(IOException.class).when(mockedInputStream).read(); + + // Create broken cache that fails to read anything + DiskBasedCache broken = spy(new DiskBasedCache(temporaryFolder.getRoot())); + doReturn(mockedInputStream).when(broken).createInputStream(any(File.class)); + + // Attempt to initialize + broken.initialize(); + + // Everything is gone + assertThat(broken.get("kilobyte"), is(nullValue())); + assertThat(broken.get("kilobyte2"), is(nullValue())); + assertThat(broken.get("kilobyte3"), is(nullValue())); + assertThat(listCachedFiles(), is(emptyArray())); + + // Verify that original cache can cope with missing files + assertThat(cache.get("kilobyte"), is(nullValue())); + assertThat(cache.get("kilobyte2"), is(nullValue())); + assertThat(cache.get("kilobyte3"), is(nullValue())); + } + + @Test + public void testManyResponseHeaders() { + Cache.Entry entry = new Cache.Entry(); + entry.data = new byte[0]; + entry.responseHeaders = new HashMap<>(); + for (int i = 0; i < 0xFFFF; i++) { + entry.responseHeaders.put(Integer.toString(i), ""); + } + cache.put("key", entry); + } + + @Test + @SuppressWarnings("TryFinallyCanBeTryWithResources") + public void testCountingInputStreamByteCount() throws IOException { + // Write some bytes + ByteArrayOutputStream out = new ByteArrayOutputStream(); + //noinspection ThrowFromFinallyBlock + try { + DiskBasedCache.writeInt(out, 1); + DiskBasedCache.writeLong(out, -1L); + DiskBasedCache.writeString(out, "hamburger"); + } finally { + //noinspection ThrowFromFinallyBlock + out.close(); + } + long bytesWritten = out.size(); + + // Read the bytes and compare the counts + CountingInputStream cis = + new CountingInputStream(new ByteArrayInputStream(out.toByteArray()), bytesWritten); + try { + assertThat(cis.bytesRemaining(), is(bytesWritten)); + assertThat(cis.bytesRead(), is(0L)); + assertThat(DiskBasedCache.readInt(cis), is(1)); + assertThat(DiskBasedCache.readLong(cis), is(-1L)); + assertThat(DiskBasedCache.readString(cis), is("hamburger")); + assertThat(cis.bytesRead(), is(bytesWritten)); + assertThat(cis.bytesRemaining(), is(0L)); + } finally { + //noinspection ThrowFromFinallyBlock + cis.close(); + } + } + + /* Serialization tests */ + + @Test + public void testEmptyReadThrowsEOF() throws IOException { + ByteArrayInputStream empty = new ByteArrayInputStream(new byte[] {}); + exception.expect(EOFException.class); + DiskBasedCache.readInt(empty); + } + + @Test + public void serializeInt() throws IOException { + ByteArrayOutputStream baos = new ByteArrayOutputStream(); + DiskBasedCache.writeInt(baos, 0); + DiskBasedCache.writeInt(baos, 19791214); + DiskBasedCache.writeInt(baos, -20050711); + DiskBasedCache.writeInt(baos, Integer.MIN_VALUE); + DiskBasedCache.writeInt(baos, Integer.MAX_VALUE); + ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray()); + assertEquals(DiskBasedCache.readInt(bais), 0); + assertEquals(DiskBasedCache.readInt(bais), 19791214); + assertEquals(DiskBasedCache.readInt(bais), -20050711); + assertEquals(DiskBasedCache.readInt(bais), Integer.MIN_VALUE); + assertEquals(DiskBasedCache.readInt(bais), Integer.MAX_VALUE); + } + + @Test + public void serializeLong() throws Exception { + ByteArrayOutputStream baos = new ByteArrayOutputStream(); + DiskBasedCache.writeLong(baos, 0); + DiskBasedCache.writeLong(baos, 31337); + DiskBasedCache.writeLong(baos, -4160); + DiskBasedCache.writeLong(baos, 4295032832L); + DiskBasedCache.writeLong(baos, -4314824046L); + DiskBasedCache.writeLong(baos, Long.MIN_VALUE); + DiskBasedCache.writeLong(baos, Long.MAX_VALUE); + ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray()); + assertEquals(DiskBasedCache.readLong(bais), 0); + assertEquals(DiskBasedCache.readLong(bais), 31337); + assertEquals(DiskBasedCache.readLong(bais), -4160); + assertEquals(DiskBasedCache.readLong(bais), 4295032832L); + assertEquals(DiskBasedCache.readLong(bais), -4314824046L); + assertEquals(DiskBasedCache.readLong(bais), Long.MIN_VALUE); + assertEquals(DiskBasedCache.readLong(bais), Long.MAX_VALUE); + } + + @Test + public void serializeString() throws Exception { + ByteArrayOutputStream baos = new ByteArrayOutputStream(); + DiskBasedCache.writeString(baos, ""); + DiskBasedCache.writeString(baos, "This is a string."); + DiskBasedCache.writeString(baos, "ファイカス"); + CountingInputStream cis = + new CountingInputStream(new ByteArrayInputStream(baos.toByteArray()), baos.size()); + assertEquals(DiskBasedCache.readString(cis), ""); + assertEquals(DiskBasedCache.readString(cis), "This is a string."); + assertEquals(DiskBasedCache.readString(cis), "ファイカス"); + } + + @Test + public void serializeHeaders() throws Exception { + ByteArrayOutputStream baos = new ByteArrayOutputStream(); + List<Header> empty = new ArrayList<>(); + DiskBasedCache.writeHeaderList(empty, baos); + DiskBasedCache.writeHeaderList(null, baos); + List<Header> twoThings = new ArrayList<>(); + twoThings.add(new Header("first", "thing")); + twoThings.add(new Header("second", "item")); + DiskBasedCache.writeHeaderList(twoThings, baos); + List<Header> emptyKey = new ArrayList<>(); + emptyKey.add(new Header("", "value")); + DiskBasedCache.writeHeaderList(emptyKey, baos); + List<Header> emptyValue = new ArrayList<>(); + emptyValue.add(new Header("key", "")); + DiskBasedCache.writeHeaderList(emptyValue, baos); + List<Header> sameKeys = new ArrayList<>(); + sameKeys.add(new Header("key", "value")); + sameKeys.add(new Header("key", "value2")); + DiskBasedCache.writeHeaderList(sameKeys, baos); + CountingInputStream cis = + new CountingInputStream(new ByteArrayInputStream(baos.toByteArray()), baos.size()); + assertEquals(DiskBasedCache.readHeaderList(cis), empty); + assertEquals(DiskBasedCache.readHeaderList(cis), empty); // null reads back empty + assertEquals(DiskBasedCache.readHeaderList(cis), twoThings); + assertEquals(DiskBasedCache.readHeaderList(cis), emptyKey); + assertEquals(DiskBasedCache.readHeaderList(cis), emptyValue); + assertEquals(DiskBasedCache.readHeaderList(cis), sameKeys); + } + + @Test + public void publicMethods() throws Exception { + // Catch-all test to find API-breaking changes. + assertNotNull(DiskBasedCache.class.getConstructor(File.class, int.class)); + assertNotNull( + DiskBasedCache.class.getConstructor(DiskBasedCache.FileSupplier.class, int.class)); + assertNotNull(DiskBasedCache.class.getConstructor(File.class)); + assertNotNull(DiskBasedCache.class.getConstructor(DiskBasedCache.FileSupplier.class)); + + assertNotNull(DiskBasedCache.class.getMethod("getFileForKey", String.class)); + } + + @Test + public void initializeIfRootDirectoryDeleted() { + temporaryFolder.delete(); + + Cache.Entry entry = randomData(101); + cache.put("key1", entry); + + assertThat(cache.get("key1"), is(nullValue())); + + // confirm that we can now store entries + cache.put("key2", entry); + assertThatEntriesAreEqual(cache.get("key2"), entry); + } + + /* Test helpers */ + + private void assertThatEntriesAreEqual(Cache.Entry actual, Cache.Entry expected) { + assertThat(actual.data, is(equalTo(expected.data))); + assertThat(actual.etag, is(equalTo(expected.etag))); + assertThat(actual.lastModified, is(equalTo(expected.lastModified))); + assertThat(actual.responseHeaders, is(equalTo(expected.responseHeaders))); + assertThat(actual.serverDate, is(equalTo(expected.serverDate))); + assertThat(actual.softTtl, is(equalTo(expected.softTtl))); + assertThat(actual.ttl, is(equalTo(expected.ttl))); + } + + private Cache.Entry randomData(int length) { + Cache.Entry entry = new Cache.Entry(); + byte[] data = new byte[length]; + new Random(42).nextBytes(data); // explicit seed for reproducible results + entry.data = data; + return entry; + } + + private File[] listCachedFiles() { + return temporaryFolder.getRoot().listFiles(); + } + + private int getEntrySizeOnDisk(String key) { + // Header size is: + // 4 bytes for magic int + // 8 + len(key) bytes for key (long length) + // 8 bytes for etag (long length + 0 characters) + // 32 bytes for serverDate, lastModified, ttl, and softTtl longs + // 4 bytes for length of header list int + // == 56 + len(key) bytes total. + return 56 + key.length(); + } +} |