/*
* Copyright 2013, The Sporting Exchange Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.betfair.cougar.netutil.nio;
import com.betfair.cougar.logging.CougarLogger;
import com.betfair.cougar.logging.CougarLoggingUtils;
import com.betfair.cougar.netutil.nio.message.RequestMessage;
import com.betfair.cougar.netutil.nio.message.ResponseMessage;
import org.apache.mina.common.IoHandlerAdapter;
import org.apache.mina.common.IoSession;
import java.io.IOException;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicLong;
import java.util.logging.Level;
/**
*
*/
public class RequestResponseManagerImpl extends IoHandlerAdapter implements RequestResponseManager {
private static final CougarLogger LOG = CougarLoggingUtils.getLogger(RequestResponseManagerImpl.class);
private final IoSession session;
private AtomicLong correlationIdGenerator = new AtomicLong();
private Map<Long, WaitingResponseHandler> callbacks = new ConcurrentHashMap<Long, WaitingResponseHandler>();
private volatile boolean broken = false;
private NioLogger nioLogger;
private long rpcTimeoutMillis; // 0 = disabled (by default)
public RequestResponseManagerImpl(IoSession session, NioLogger nioLogger, long rpcTimeoutMillis) {
this.session = session;
this.nioLogger = nioLogger;
this.rpcTimeoutMillis = rpcTimeoutMillis;
}
public void checkForExpiredRequests() {
// do this in 2 steps so we don't need a lock around the map access
Set<Long> expiredCorrelationIds = new HashSet<Long>();
long now = System.currentTimeMillis();
for (Long key : callbacks.keySet()) {
WaitingResponseHandler handler = callbacks.get(key);
if (handler != null && handler.expiryTime < now) {
expiredCorrelationIds.add(key);
}
}
for (Long key : expiredCorrelationIds) {
WaitingResponseHandler handler = callbacks.remove(key);
// response might have come back in between
if (handler != null) {
handler.handler.timedOut();
}
}
}
@Override
public int getOutstandingRequestCount() {
return callbacks.size();
}
@Override
public long sendRequest(byte[] message, ResponseHandler handler) throws IOException {
if (!broken) {
long correlationId = correlationIdGenerator.incrementAndGet();
RequestMessage req = new RequestMessage(correlationId, message);
callbacks.put(correlationId, new WaitingResponseHandler(getExpiryTime(), handler));
session.write(req);
return correlationId;
}
else {
throw new IOException("This RequestResponseManager is broken, most likely cause is the session has been terminated");
}
}
private long getExpiryTime() {
if (rpcTimeoutMillis == 0) {
return Long.MAX_VALUE;
}
return System.currentTimeMillis() + rpcTimeoutMillis;
}
@Override
public void messageReceived(IoSession session, Object message) {
ResponseMessage resp = (ResponseMessage) message;
WaitingResponseHandler handler = callbacks.remove(resp.getCorrelationId());
// could be null if it already timed out
if (handler != null) {
handler.handler.responseReceived(resp);
}
}
@Override
public void exceptionCaught(IoSession session, Throwable cause) {
if (cause instanceof IOException) {
LOG.log(Level.FINE, "IO exception from session "+NioUtils.getSessionId(session), cause);
} else {
LOG.log(Level.WARNING, "Unexpected exception from session "+NioUtils.getSessionId(session), cause);
}
nioLogger.log(NioLogger.LoggingLevel.SESSION, session, "RequestResponseManager - %s received: %s - closing session", cause.getClass().getSimpleName(), cause.getMessage());
session.close();
}
@Override
public void sessionClosed(IoSession session) {
broken = true;
final LinkedList<WaitingResponseHandler> callbackList = new LinkedList<WaitingResponseHandler>(callbacks.values());
callbacks.clear();
for (WaitingResponseHandler handler : callbackList) {
handler.handler.sessionClosed();
}
LOG.log(Level.INFO, "Notified "+callbackList.size() +" outstanding requests for session "+NioUtils.getSessionId(session));
}
private class WaitingResponseHandler {
long expiryTime;
ResponseHandler handler;
private WaitingResponseHandler(long expiryTime, ResponseHandler handler) {
this.expiryTime = expiryTime;
this.handler = handler;
}
}
}