[HADOOP-151] RPC code has socket leak?

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.1.0, 0.1.1, 0.2.0
• Fix Version/s: 0.2.0
• Component/s: ipc
• Assignee: Doug Cutting
• Reporter: Peter Sutter
• Created: 20/Apr/06 05:18
• Updated: 03/Aug/06 17:46
• Resolved: 20/Apr/06 06:57

Description

In RPC.java, the field named CLIENT should be neither static, nor a field of RPC. It should be (a) a private nonstatic field of InvocationHandler(),and (just further down), (b) a local variable in the RPC.call() method below. The comment above the declaration was a bit of giveaway:

//TODO [e-mail]: static client or non-static client?
private static Client CLIENT;

private static class Invoker implements InvocationHandler {
private InetSocketAddress address;

public Invoker(InetSocketAddress address, Configuration conf) {
this.address = address;
CLIENT = (Client) conf.getObject(Client.class.getName());
if(CLIENT == null)

{ CLIENT = new Client(ObjectWritable.class, conf); conf.setObject(Client.class.getName(), CLIENT); }

}

public Object invoke(Object proxy, Method method, Object[] args)
throws Throwable

{ ObjectWritable value = (ObjectWritable) CLIENT.call(new Invocation(method, args), address); return value.get(); }

}

/** Construct a client-side proxy object that implements the named protocol,

• talking to a server at the named address. */
  public static Object getProxy(Class protocol, InetSocketAddress addr, Configuration conf)
  Unknown macro: { return Proxy.newProxyInstance(protocol.getClassLoader(), new Class[] { protocol }, new Invoker(addr, conf)); }

/** Expert: Make multiple, parallel calls to a set of servers. */
public static Object[] call(Method method, Object[][] params,
InetSocketAddress[] addrs, 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) conf.getObject(Client.class.getName());
if(CLIENT == null)

{ CLIENT = new Client(ObjectWritable.class, conf); conf.setObject(Client.class.getName(), CLIENT); }

Writable[] wrappedValues = CLIENT.call(invocations, addrs);

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;
}.