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/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 2009-2013 Oracle and/or its affiliates. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
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package com.sun.grizzly.util;

import java.util.Queue;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.logging.Level;

/**
 *
 * @author gustav trede
 */
public class DataStructures {
    private final static Class LTQclass;

    static {
        String className = null;
        
        Class c;
        try {
            JdkVersion jdkVersion = JdkVersion.getJdkVersion();
            JdkVersion minimumVersion = JdkVersion.parseVersion("1.7.0");
            
            className = (minimumVersion.compareTo(jdkVersion) <= 0)
                    ? "java.util.concurrent.LinkedTransferQueue"
                    : "com.sun.grizzly.util.LinkedTransferQueue";
            
            c = getAndVerify(className);
            LoggerUtils.getLogger().log(Level.FINE, "USING LTQ class:{0}", c);
        } catch (Throwable t) {
            LoggerUtils.getLogger().log(Level.FINE,
                    "failed loading datastructure class:" + className +
                    " fallback to embedded one", t);
            
            c = LinkedBlockingQueue.class; // fallback to LinkedBlockingQueue
        }
        
        LTQclass = c;
    }
    
    private static Class getAndVerify(String cname) throws Throwable {
        Class cl = DataStructures.class.getClassLoader().loadClass(cname);
        return cl.newInstance().getClass();
    }

    public static BlockingQueue getLTQinstance() {
        try {
            return (BlockingQueue) LTQclass.newInstance();
        } catch (Exception ea) {
            throw new RuntimeException(ea);
        }
    }

    @SuppressWarnings("unchecked")
    public static  BlockingQueue getLTQinstance(Class t) {
        try {
            return (BlockingQueue) LTQclass.newInstance();
        } catch (Exception ea) {
            throw new RuntimeException(ea);
        }
    }

    @SuppressWarnings("unchecked")
    public static Queue getCLQinstance() {
        return new ConcurrentLinkedQueue();
    }

    @SuppressWarnings("unchecked")
    public static  Queue getCLQinstance(Class t) {
        return new ConcurrentLinkedQueue();
    }
}