理解这个RPC是不是的先去理解哈动态代理 好多invoke，还有Socket网络编程

先来张eclipse下IPC源码图：

先来看看RPC.java，既然是动态代理，自然会想到Invoke()方法了，先来看看RPC中的Invoker中的invoke()方法

private static class Invoker implements InvocationHandler {
private InetSocketAddress address;
private UserGroupInformation ticket;
private Client client;
private boolean isClosed = false;

public Invoker(InetSocketAddress address, UserGroupInformation ticket,
Configuration conf, SocketFactory factory) {
this.address = address;
this.ticket = ticket;
this.client = CLIENTS.getClient(conf, factory);
}

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 = (ObjectWritable)
client.call(new Invocation(method, args), address,
method.getDeclaringClass(), ticket);
if (logDebug) {
long callTime = System.currentTimeMillis() - startTime;
LOG.debug("Call: " + method.getName() + " " + callTime);
}
return value.get();
}

/* close the IPC client that's responsible for this invoker's RPCs */
synchronized private void close() {
if (!isClosed) {
isClosed = true;
CLIENTS.stopClient(client);
}
}
}

可以看出动态代理里的invoke()方法其实是RPC里的invocation对方法名，参数做了封装，可以看invocation类的