java Semaphores示例：限制Url连接数，semaphores示例,package cn.o

java Semaphores示例：限制Url连接数，semaphores示例,package cn.o

package cn.outofmemory;import java.util.concurrent.Semaphore; //import other packagepublic class ConnectionLimiter {   private final Semaphore semaphore;   private ConnectionLimiter(int maxConcurrentRequests) {       semaphore = new Semaphore(maxConcurrentRequests);   }   public URLConnection acquire(URL url) throws InterruptedException,                                                IOException {       semaphore.acquire();       return url.openConnection();   }   public void release(URLConnection conn) {       try {           /*           * ... clean up here           */       } finally {           semaphore.release();       }   }}