/*
 * Copyright 2007-2010 Sun Microsystems, Inc.
 *
 * This file is part of Project Darkstar Server.
 *
 * Project Darkstar Server is free software: you can redistribute it
 * and/or modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation and
 * distributed hereunder to you.
 *
 * Project Darkstar Server is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * --
 */

package com.sun.sgs.impl.util;

import com.sun.sgs.impl.sharedutil.Objects;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.ThreadFactory;

/**
 * A custom implementation of a {@code ThreadFactory} that assigns a
 * configurable name to each thread.
 */
public class NamedThreadFactory implements ThreadFactory {
    
    // the prefix to assign to the name of each thread generated by the factory
    private final String name;
    
    // a running count of the number of threads generated by this factory
    private final AtomicInteger count;

    /**
     * Creates a new {@code NamedThreadFactory} that names each thread that
     * it creates using the given {@code name}.
     *
     * @param name the prefix to use for each thread's name
     */
    public NamedThreadFactory(String name) {
        Objects.checkNull("name", name);
        this.name = name;
        this.count = new AtomicInteger();
    }

    /**
     * Constructs a new {@code Thread} for the given {@code Runnable}.  The
     * name of the returned {@code Thread} is equal to the current count of the
     * number of threads that have been created thus far with this factory
     * appended to the name used to construct this factory.
     *
     * @param r the {@code Runnable} to be executed by the new thread
     * @return new thread associated with the given {@code Runnable}
     */
    @Override
    public Thread newThread(Runnable r) {
        return new Thread(r, name + "-" + count.getAndIncrement());
    }

}