/**
* Sends an RPC request to the given {@link InetSocketAddress}.
*
* @param remoteSocketAddress the remote address to send the request to
* @param request the RPC request to send
* @return the return value of the RPC call, possibly <code>null</code>
* @throws Throwable any exception that is thrown by the remote receiver of the RPC call
*/
Object sendRPCRequest(final InetSocketAddress remoteSocketAddress, final RPCRequest request)
throws Throwable {
if (this.shutdownRequested.get())
throw new IOException("Shutdown of RPC service has already been requested");
final long start = System.currentTimeMillis();
final DatagramPacket[] packets = this.messageToPackets(remoteSocketAddress, request);
final Integer messageID = Integer.valueOf(request.getMessageID());
final RPCRequestMonitor requestMonitor = new RPCRequestMonitor();
this.pendingRequests.put(messageID, requestMonitor);
RPCResponse rpcResponse = null;
int numberOfRetries;
try {
numberOfRetries = this.networkThread.send(packets);
// Wait for the response
synchronized (requestMonitor) {
while (true) {
if (requestMonitor.rpcResponse != null) {
rpcResponse = requestMonitor.rpcResponse;
break;
}
final long sleepTime = RPC_TIMEOUT - (System.currentTimeMillis() - start);
if (sleepTime > 0L) requestMonitor.wait(sleepTime);
else break;
}
}
} finally {
// Request is no longer pending
this.pendingRequests.remove(messageID);
}
if (rpcResponse == null)
throw new IOException(
"Unable to complete RPC of method "
+ request.getMethodName()
+ " on "
+ remoteSocketAddress);
// Report the successful call to the statistics module
final String methodName = request.getMethodName();
this.statistics.reportSuccessfulTransmission(methodName, packets.length, numberOfRetries);
this.statistics.reportRTT(methodName, (int) (System.currentTimeMillis() - start));
// TODO: Send clean up message
if (rpcResponse instanceof RPCReturnValue) return ((RPCReturnValue) rpcResponse).getRetVal();
throw ((RPCThrowable) rpcResponse).getThrowable();
}
/**
* Processes an incoming RPC response.
*
* @param rpcResponse the RPC response to be processed
*/
void processIncomingRPCResponse(final RPCResponse rpcResponse) {
final Integer messageID = Integer.valueOf(rpcResponse.getMessageID());
final RPCRequestMonitor requestMonitor = this.pendingRequests.get(messageID);
// The caller has already timed out or received an earlier response
if (requestMonitor == null) return;
synchronized (requestMonitor) {
requestMonitor.rpcResponse = rpcResponse;
requestMonitor.notify();
}
}
