DataStructures.java

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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, CLQclass;

    static{
        Class<?> LTQ = LinkedBlockingQueue.class ,
                 CLQ = LinkedBlockingQueue.class;
        int jver = 0;
        try{
            jver = Integer.valueOf(System.getProperty("java.version").
                    substring(0,3).replace(".", ""));
            if (jver > 16){
                CLQ = ConcurrentLinkedQueue.class;
                LTQ = getAndVerify("maskedclasses.LinkedTransferQueue");
            }else
            if (jver == 16){
                LTQ = getAndVerify("maskedclasses.LinkedTransferQueue");
                CLQ = getAndVerify("maskedclasses.ConcurrentLinkedQueue");
            }
        }catch(Throwable t){
            LoggerUtils.getLogger().log(Level.FINE,
                 "failed loading grizzly version of datastructure classes," +
                 " dont worry we load other classes instead.", t);
        }
        LTQclass =  LTQ;
        CLQclass =  CLQ;
        LoggerUtils.getLogger().fine("JVM version "+jver+" detected," +
               " grizzly loaded datastructure classes: "+LTQclass+" "+CLQclass);
    }

    private final static Class<?> getAndVerify(String cname) throws Throwable{
        Class<?> cl = DataStructures.class.getClassLoader().loadClass(cname);
        return cl.newInstance().getClass();
    }

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

    @SuppressWarnings("unchecked")
    public final static <T>BlockingQueue<T>  getLTQinstance(Class<T> t){
        try{
            return  (BlockingQueue<T>) LTQclass.newInstance();
        }catch(Exception ea){
            throw new RuntimeException(ea);
        }
    }
    
    public final static Queue<?> getCLQinstance(){
        try{
            return (Queue<?>) CLQclass.newInstance();
        }catch(Exception ea){
            throw new RuntimeException(ea);
        }
    }

    @SuppressWarnings("unchecked")
    public final static <T>Queue<T> getCLQinstance(Class<T> t){
        try{
            return (Queue<T>) CLQclass.newInstance();
        }catch(Exception ea){
            throw new RuntimeException(ea);
        }
    }

}