@Override
public void close() throws IOException {
closed = true;
pool.shutdown();
}
@Override
public Transaction createTransaction(final TransferDirection direction) throws IOException {
if (closed) {
throw new IllegalStateException("Client is closed");
}
final String portId = getPortIdentifier(direction);
if (portId == null) {
throw new IOException(
"Could not find Port with name '" + portName + "' for remote NiFi instance");
}
final EndpointConnection connectionState = pool.getEndpointConnection(direction, getConfig());
if (connectionState == null) {
return null;
}
final Transaction transaction;
try {
transaction =
connectionState
.getSocketClientProtocol()
.startTransaction(connectionState.getPeer(), connectionState.getCodec(), direction);
} catch (final Throwable t) {
pool.terminate(connectionState);
throw new IOException(
"Unable to create Transaction to communicate with " + connectionState.getPeer(), t);
}
// Wrap the transaction in a new one that will return the EndpointConnectionState back to the
// pool whenever
// the transaction is either completed or canceled.
final AtomicReference<EndpointConnection> connectionStateRef =
new AtomicReference<>(connectionState);
return new Transaction() {
@Override
public void confirm() throws IOException {
transaction.confirm();
}
@Override
public TransactionCompletion complete() throws IOException {
try {
return transaction.complete();
} finally {
final EndpointConnection state = connectionStateRef.get();
if (state != null) {
pool.offer(connectionState);
connectionStateRef.set(null);
}
}
}
@Override
public void cancel(final String explanation) throws IOException {
try {
transaction.cancel(explanation);
} finally {
final EndpointConnection state = connectionStateRef.get();
if (state != null) {
pool.terminate(connectionState);
connectionStateRef.set(null);
}
}
}
@Override
public void error() {
try {
transaction.error();
} finally {
final EndpointConnection state = connectionStateRef.get();
if (state != null) {
pool.terminate(connectionState);
connectionStateRef.set(null);
}
}
}
@Override
public void send(final DataPacket dataPacket) throws IOException {
transaction.send(dataPacket);
}
@Override
public void send(final byte[] content, final Map<String, String> attributes)
throws IOException {
transaction.send(content, attributes);
}
@Override
public DataPacket receive() throws IOException {
return transaction.receive();
}
@Override
public TransactionState getState() throws IOException {
return transaction.getState();
}
@Override
public Communicant getCommunicant() {
return transaction.getCommunicant();
}
};
}