### Question:
DiskLruCache implements Closeable { public synchronized Value get(String key) throws IOException { checkNotClosed(); Entry entry = lruEntries.get(key); if (entry == null) { return null; } if (!entry.readable) { return null; } for (File file : entry.cleanFiles) { if (!file.exists()) { return null; } } redundantOpCount++; journalWriter.append(READ); journalWriter.append(' '); journalWriter.append(key); journalWriter.append('\n'); if (journalRebuildRequired()) { executorService.submit(cleanupCallable); } return new Value(key, entry.sequenceNumber, entry.cleanFiles, entry.lengths); } private  DiskLruCache(File directory, int appVersion, int valueCount, long maxSize); static DiskLruCache open(File directory, int appVersion, int valueCount, long maxSize); synchronized Value get(String key); Editor edit(String key); File getDirectory(); synchronized long getMaxSize(); synchronized void setMaxSize(long maxSize); synchronized long size(); synchronized boolean remove(String key); synchronized boolean isClosed(); synchronized void flush(); synchronized void close(); void delete();  }### Answer:
@Test public void readingTheSameFileMultipleTimes() throws Exception { set("a", "a", "b"); DiskLruCache.Value value = cache.get("a"); assertThat(value.getFile(0)).isSameInstanceAs(value.getFile(0)); }
@Test public void aggressiveClearingHandlesRead() throws Exception { deleteDirectory(cacheDir); assertThat(cache.get("a")).isNull(); }
@Test public void readingTheSameFileMultipleTimes() throws Exception { set("a", "a", "b"); DiskLruCache.Value value = cache.get("a"); assertThat(value.getFile(0)).isSameAs(value.getFile(0)); }
@Test public void aggressiveClearingHandlesRead() throws Exception { FileUtils.deleteDirectory(cacheDir); assertThat(cache.get("a")).isNull(); }