/** Expert: Make multiple, parallel calls to a set of servers. */
public static Object[] call(
Method method,
Object[][] params,
InetSocketAddress[] addrs,
UserGroupInformation ticket,
Configuration conf)
throws IOException {
Invocation[] invocations = new Invocation[params.length];
for (int i = 0; i < params.length; i++) invocations[i] = new Invocation(method, params[i]);
Client client = CLIENTS.getClient(conf);
try {
Writable[] wrappedValues =
client.call(invocations, addrs, method.getDeclaringClass(), ticket);
if (method.getReturnType() == Void.TYPE) {
return null;
}
Object[] values = (Object[]) Array.newInstance(method.getReturnType(), wrappedValues.length);
for (int i = 0; i < values.length; i++)
if (wrappedValues[i] != null) values[i] = ((ObjectWritable) wrappedValues[i]).get();
return values;
} finally {
CLIENTS.stopClient(client);
}
}
/**
* Stop a RPC client connection A RPC client is closed only when its reference count becomes
* zero.
*/
private void stopClient(Client client) {
synchronized (this) {
client.decCount();
if (client.isZeroReference()) {
clients.remove(client.getSocketFactory());
}
}
if (client.isZeroReference()) {
client.stop();
}
}
/**
* Construct & cache an IPC client with the user-provided SocketFactory if no cached client
* exists.
*
* @param conf Configuration
* @return an IPC client
*/
private synchronized Client getClient(Configuration conf, SocketFactory factory) {
// Construct & cache client. The configuration is only used for timeout,
// and Clients have connection pools. So we can either (a) lose some
// connection pooling and leak sockets, or (b) use the same timeout for all
// configurations. Since the IPC is usually intended globally, not
// per-job, we choose (a).
Client client = clients.get(factory);
if (client == null) {
client = new Client(ObjectWritable.class, conf, factory);
clients.put(factory, client);
} else {
client.incCount();
}
return client;
}
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
final boolean logDebug = LOG.isDebugEnabled();
long startTime = 0;
if (logDebug) {
startTime = System.currentTimeMillis();
}
ObjectWritable value = null;
try {
value =
(ObjectWritable)
client.call(
new Invocation(method, args), getAddress(), protocol, ticket, rpcTimeout);
} catch (RemoteException re) {
throw re;
} catch (ConnectException ce) {
needCheckDnsUpdate = true;
throw ce;
} catch (NoRouteToHostException nrhe) {
needCheckDnsUpdate = true;
throw nrhe;
} catch (PortUnreachableException pue) {
needCheckDnsUpdate = true;
throw pue;
} catch (UnknownHostException uhe) {
needCheckDnsUpdate = true;
throw uhe;
}
if (logDebug) {
long callTime = System.currentTimeMillis() - startTime;
LOG.debug("Call: " + method.getName() + " " + callTime);
}
return value.get();
}
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
long startTime = 0;
if (LOG.isDebugEnabled()) {
startTime = Time.now();
}
ObjectWritable value =
(ObjectWritable)
client.call(RPC.RpcKind.RPC_WRITABLE, new Invocation(method, args), remoteId);
if (LOG.isDebugEnabled()) {
long callTime = Time.now() - startTime;
LOG.debug("Call: " + method.getName() + " " + callTime);
}
return value.get();
}