void open() {
if (!running) {
running = true;
writer =
new Thread() {
public void run() {
try {
processQueue();
} catch (Throwable ex) {
warn(ex, ex.getMessage());
try {
close();
} catch (Exception ignored) {
warn(ignored, ignored.getMessage());
}
}
}
};
writer.setPriority(Thread.MAX_PRIORITY);
writer.setDaemon(true);
writer.setName("DataFileAppender Writer Thread");
writer.start();
}
}
Future<Boolean> sync() throws IOException {
int spinnings = 0;
int limit = 100;
while (true) {
try {
if (batching.compareAndSet(false, true)) {
Future result = null;
if (nextWriteBatch != null) {
result = new WriteFuture(nextWriteBatch.latch);
batchQueue.put(nextWriteBatch);
nextWriteBatch = null;
} else {
result = new WriteFuture(new CountDownLatch(0));
}
batching.set(false);
return result;
} else {
// Spin waiting for new batch ...
if (spinnings <= limit) {
spinnings++;
continue;
} else {
Thread.sleep(250);
continue;
}
}
} catch (InterruptedException ex) {
throw new IllegalStateException(ex.getMessage(), ex);
}
}
}
void close() throws IOException {
try {
if (!shutdown) {
if (running) {
shutdown = true;
while (batching.get() == true) {
Thread.sleep(250);
}
if (nextWriteBatch != null) {
batchQueue.put(nextWriteBatch);
nextWriteBatch = null;
} else {
batchQueue.put(NULL_BATCH);
}
} else {
shutdownDone.countDown();
}
}
shutdownDone.await();
} catch (InterruptedException e) {
throw new InterruptedIOException();
}
}
private WriteBatch enqueue(WriteCommand writeRecord) throws IOException {
WriteBatch currentBatch = null;
int spinnings = 0;
int limit = 100;
while (true) {
if (shutdown) {
throw new IOException("DataFileAppender Writer Thread Shutdown!");
}
if (firstAsyncException.get() != null) {
throw new IOException(firstAsyncException.get());
}
try {
if (batching.compareAndSet(false, true) && !shutdown) {
if (nextWriteBatch == null) {
DataFile file = journal.getCurrentWriteFile();
boolean canBatch = false;
currentBatch = new WriteBatch(file, file.getLength(), writeRecord);
canBatch = currentBatch.canBatch(writeRecord);
if (!canBatch) {
file = journal.rotateWriteFile();
currentBatch = new WriteBatch(file, file.getLength(), writeRecord);
}
WriteCommand controlRecord = new WriteCommand(new Location(), null, false);
currentBatch.doFirstBatch(controlRecord, writeRecord);
if (!writeRecord.sync) {
inflightWrites.put(controlRecord.location, controlRecord);
inflightWrites.put(writeRecord.location, writeRecord);
nextWriteBatch = currentBatch;
batching.set(false);
} else {
batchQueue.put(currentBatch);
batching.set(false);
}
break;
} else {
boolean canBatch = nextWriteBatch.canBatch(writeRecord);
if (canBatch && !writeRecord.sync) {
nextWriteBatch.doAppendBatch(writeRecord);
inflightWrites.put(writeRecord.location, writeRecord);
currentBatch = nextWriteBatch;
batching.set(false);
break;
} else if (canBatch && writeRecord.sync) {
nextWriteBatch.doAppendBatch(writeRecord);
batchQueue.put(nextWriteBatch);
currentBatch = nextWriteBatch;
nextWriteBatch = null;
batching.set(false);
break;
} else {
batchQueue.put(nextWriteBatch);
nextWriteBatch = null;
batching.set(false);
}
}
} else {
// Spin waiting for new batch ...
if (spinnings <= limit) {
spinnings++;
continue;
} else {
Thread.sleep(250);
continue;
}
}
} catch (InterruptedException ex) {
throw new IllegalStateException(ex.getMessage(), ex);
}
}
return currentBatch;
}