/*******************************************************************************
* This program and the accompanying materials
* are made available under the terms of the Common Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/cpl-v10.html
*
* Contributors:
* Peter Smith
*******************************************************************************/
package org.boris.xlloop.util;
import java.io.IOException;
import java.util.Arrays;
import java.util.Collection;
import java.util.concurrent.ConcurrentLinkedQueue;
import org.boris.xlloop.IFunctionContext;
import org.boris.xlloop.IFunctionHandler;
import org.boris.xlloop.RequestException;
import org.boris.xlloop.RequestExecutor;
import org.boris.xlloop.xloper.XLoper;
/**
* A basic function server that hosts multiple child request executors and
* delegates requests (in a round-robin fashion).
*/
public class CompositeFunctionServer implements IFunctionHandler
{
private Collection executors;
private volatile CircularIterator iterator;
public CompositeFunctionServer(RequestExecutor[] executors) {
this.executors = new ConcurrentLinkedQueue(Arrays.asList(executors));
this.iterator = new CircularIterator(this.executors);
}
public void add(RequestExecutor re) {
executors.add(re);
iterator = new CircularIterator(executors);
}
public void remove(RequestExecutor re) {
executors.remove(re);
iterator = new CircularIterator(executors);
}
public XLoper execute(IFunctionContext context, String name, XLoper[] args) throws RequestException {
try {
return ((RequestExecutor) iterator.next()).execute(name, args);
} catch (IOException e) {
throw new RequestException(e);
}
}
public boolean hasFunction(String name) {
return true;
}
}