private void initIndexContent(DataInputStream in) throws IOException {
try {
while (true) {
char flag = (char) in.readByte();
String key = in.readUTF();
if (flag == DELETE) {
lruEntries.remove(key);
return;
}
DiskLruCacheEntry entry = lruEntries.get(key);
if (entry == null) {
entry = new DiskLruCacheEntry(this, key);
lruEntries.put(key, entry);
}
switch (flag) {
case CLEAN:
entry.size = in.readInt();
break;
case UPDATE:
case WRITE:
entry.clean(); // reset to clean or deleted
break;
case READ:
// this work was already done by calling lruEntries.get()
break;
default:
throw new IOException("unexpected index line: " + flag + ":" + key);
}
}
} catch (EOFException e) {
// end
}
}
/* (non-Javadoc)
* @see org.xidea.android.impl.io.DiskLruCacheIF#close()
*/
@Override
public synchronized void close() throws IOException {
if (indexWriter == null) {
return; // already closed
}
for (final DiskLruCacheEntry entry : new ArrayList<DiskLruCacheEntry>(lruEntries.values())) {
entry.clean();
}
trimToSize();
indexWriter.close();
indexWriter = null;
}
@Override
public synchronized InputStream getWritebackFilter(
InputStream in, String key, int pos, final Callback<Boolean> complete) throws IOException {
validate(key);
DiskLruCacheEntry entry = lruEntries.get(key);
if (entry == null) {
entry = new DiskLruCacheEntry(this, key);
lruEntries.put(key, entry);
}
boolean readable = entry.isReadable();
InputStream wrapper = entry.getWritebackFilter(in, pos, complete);
// flush the index before creating files to prevent file leaks
if (wrapper != null) {
writeIndex(readable ? UPDATE : WRITE, entry);
return wrapper; //
}
return in;
}
@Override
public synchronized InputStream get(String key) throws IOException {
validate(key);
final DiskLruCacheEntry entry = lruEntries.get(key);
if (entry != null) {
InputStream in = entry.newInputStream();
if (in != null) {
redundantOpCount++;
writeIndex(READ, entry); // .flush(); do not flush immediately for
// performance
if (indexRebuildRequired()) {
executorService.submit(cleanupCallable);
}
}
return in;
}
return null;
}
/**
* Creates a new index that omits redundant information. This replaces the current index if it
* exists.
*/
private synchronized void rebuildIndex() throws IOException {
if (indexWriter != null) {
indexWriter.close();
}
File indexFileTmp = new File(directory, INDEX_FILE + ".tmp");
indexWriter = new DataOutputStream(new FileOutputStream(indexFileTmp));
indexWriter.writeUTF(MAGIC);
indexWriter.writeByte('\n');
for (final DiskLruCacheEntry entry : lruEntries.values()) {
boolean readable = entry.isReadable();
writeIndex(
entry.isWriting() ? (readable ? UPDATE : WRITE) : (readable ? CLEAN : DELETE), entry);
}
indexWriter.close();
File indexFile = new File(directory, INDEX_FILE);
indexFileTmp.renameTo(indexFile);
indexWriter = new DataOutputStream(new FileOutputStream(indexFile, true));
}
/* (non-Javadoc)
* @see org.xidea.android.impl.io.DiskLruCacheIF#remove(java.lang.String)
*/
@Override
public synchronized boolean remove(String key) throws IOException {
validate(key);
final DiskLruCacheEntry entry = lruEntries.get(key);
if (entry == null) {
return false;
}
int s = entry.size;
entry.delete();
size -= s;
lruEntries.remove(key);
redundantOpCount++;
writeIndex(DELETE, entry);
if (indexRebuildRequired()) {
executorService.submit(cleanupCallable);
}
return true;
}
private void initIndex(DataInputStream in) throws IOException {
try {
final String magic = in.readUTF();
final char blank = (char) in.readByte();
if (!MAGIC.equals(magic) || '\n' != blank) {
throw new IOException("unexpected index header: [" + magic + ", " + blank + "]");
}
initIndexContent(in);
for (final Iterator<DiskLruCacheEntry> i = lruEntries.values().iterator(); i.hasNext(); ) {
final DiskLruCacheEntry entry = i.next();
if (entry.isReadable()) {
size += entry.size;
} else {
entry.delete();
i.remove();
}
}
} finally {
IOUtil.closeQuietly(in);
}
}
