一个异步获取EJB 服务实例：

EJBServer 模拟服务端：

package com.concurrent.deep;/** * @ClassName: EJBServer * @Description: 提供EJB服务的对象。 * @author Comsys-Administrator * @date 2012-11-30 下午11:17:36 * */public class EJBServer {	/*	 * 实例花EJB对象。	 */		public EJBServer() throws InterruptedException {		getConnection();		System.out.println("开始实例化EJBServer对象start................");		try {			System.out.println("实例化EJBServer对象doing................");			Thread.sleep(200);		} catch (InterruptedException e) {			//e.printStackTrace();			System.out.println("实例化出异常。。。。。。");			throw e;		}				System.out.println("实例化EJBServer对象 end................");	}	//建立客户端和服务端的连接 。。。。。。。。。	public static void getConnection() throws InterruptedException{		System.out.println("开始与EJBServer连接start................");		try {			System.out.println("EJBServer连接doing................");			Thread.sleep(100);		} catch (InterruptedException e) {			//e.printStackTrace();			System.out.println("EJBServer连接出异常。。。。。。");			throw e;		}				System.out.println("成功获取EJBServer连接 end................");	}	}

package com.concurrent.deep;/** * @ClassName: EJBTools * @Description: 获取EJB实例的工具类 * @author Comsys-Administrator * @date 2012-11-30 下午11:16:48 *  */public class EJBTools {	private static EJBServer instance;	public static EJBServer getInstance() {		if (instance == null) {			try {				instance = new EJBServer();			} catch (InterruptedException e) {				System.out.println("获取EJB连接失败或者是获取EJB实例失败");			}		}		return instance;	}	public static void main(String[] args) {		EJBServer server=	EJBTools.getInstance();		if(server==null){			System.out.println("获取EJB连接失败或者是获取EJB实例失败");		}else{			System.out.println("done!");		}	}}

异步获取EJB服务的方法：

package com.concurrent.deep;import java.util.concurrent.Callable;import java.util.concurrent.ExecutionException;import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;import java.util.concurrent.Future;import java.util.concurrent.TimeUnit;import java.util.concurrent.TimeoutException;/** * @ClassName: SyncEJBTools * @Description: 异步获取EJB实例的工具类 * @author Comsys-Administrator * @date 2012-11-30 下午11:16:48 *  */public class SyncEJBTools {	private static EJBServer instance;	public static EJBServer getInstance() {		int timeout = 2; //秒.          ExecutorService executor = Executors.newSingleThreadExecutor();          Future
    
      future = executor.submit(new Callable
     
      (){			@Override			public EJBServer call() throws Exception {				return new EJBServer();			}        	        });// 将任务提交到线程池中             try {             	instance = future.get(timeout*40, TimeUnit.MILLISECONDS);// 设定在200毫秒的时间内完成               System.out.println(instance);          } catch (InterruptedException e) {              System.out.println("线程中断出错。");              future.cancel(true);// 中断执行此任务的线程             } catch (ExecutionException e) {                 System.out.println("线程服务出错。");              future.cancel(true);// 中断执行此任务的线程             } catch (TimeoutException e) {// 超时异常                 System.out.println("超时。");                 future.cancel(true);// 中断执行此任务的线程             }finally{              System.out.println("线程服务关闭。");              executor.shutdown();          }  		return instance;	}	public static void main(String[] args) {		EJBServer server=	SyncEJBTools.getInstance();		if(server==null){			System.out.println("获取EJB连接失败或者是获取EJB实例失败");		}else{			System.out.println("done!");		}	}}
     
    

一个通用的方式来获取EJBServer的方法。

package com.concurrent.deep;import java.util.concurrent.Callable;import java.util.concurrent.ExecutionException;import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;import java.util.concurrent.Future;import java.util.concurrent.TimeUnit;import java.util.concurrent.TimeoutException;/** * @ClassName: SyncEJBTools * @Description: 异步获取EJB实例的工具类 * @author Comsys-Administrator * @date 2012-11-30 下午11:16:48 *  */public class SyncGernicEJBTools
    
      {	private  T instance;	public  T getInstance(final Class
     
       tclass) {		int timeout = 2; //秒.          ExecutorService executor = Executors.newSingleThreadExecutor();          Future
      
        future = executor.submit(new Callable
       
        (){			@Override			public T call() throws Exception {				return tclass.newInstance();			}        	        });// 将任务提交到线程池中             try {             	instance = future.get(timeout*400, TimeUnit.MILLISECONDS);// 设定在200毫秒的时间内完成               System.out.println(instance);          } catch (InterruptedException e) {              System.out.println("线程中断出错。");              future.cancel(true);// 中断执行此任务的线程             } catch (ExecutionException e) {                 System.out.println("线程服务出错。");              future.cancel(true);// 中断执行此任务的线程             } catch (TimeoutException e) {// 超时异常                 System.out.println("超时。");                 future.cancel(true);// 中断执行此任务的线程             }finally{              System.out.println("线程服务关闭。");              executor.shutdown();          }  		return instance;	}	public static void main(String[] args) {		SyncGernicEJBTools
        
          tools=new SyncGernicEJBTools
         
          (); EJBServer server= (EJBServer) tools.getInstance(EJBServer.class); if(server==null){ System.out.println("获取EJB连接失败或者是获取EJB实例失败"); }else{ System.out.println("done!"); } }}