Question

我有一个类似这样的方法:(我在android项目中使用此代码）

    void flushAndClose(Socket socket,String s1){
     if (socket!=null)
         try {
             OutputStream outputStream=socket.getOutputStream();
             PrintStream printStream=new PrintStream(outputStream,true);
             printStream.write(s1.getBytes());
             printStream.close(); //This only closes outputStream. Am I wrong?
             //Error will occur in inner try-catch
             //Again try catch to countinue next statement
             //Actually I call method twice so I added second try-catch just for trying it with one method.
             try {
                 System.out.println("socket.isClosed() --> "+socket.isClosed());//Returns false
                 flushAndClose(socket,s1);
             }catch (Exception e){ 
                 e.printStackTrace();
                 System.out.println(e.getMessage());//"Socket is closed"
             }
         } catch (IOException e) {
             e.printStackTrace();
         }
}

这是来自grepcode.com

的getOutputStream（）方法

825     public OutputStream getOutputStream() throws IOException {
826         if (isClosed())
827             throw new SocketException("Socket is closed");
828         if (!isConnected())
829             throw new SocketException("Socket is not connected");
830         if (isOutputShutdown())
831             throw new SocketException("Socket output is shutdown");
832         final Socket s = this;
833         OutputStream os = null;
834         try {
835             os = (OutputStream)
836                 AccessController.doPrivileged(new PrivilegedExceptionAction() {
837                     public Object More ...run() throws IOException {
838                         return impl.getOutputStream();
839                     }
840                 });
841         } catch (java.security.PrivilegedActionException e) {
842             throw (IOException) e.getException();
843         }
844         return os;
845     }

我得到s1值一次不是两次。我知道在finally块中调用此方法printStream.close();将解决此问题。

但是我无法理解为什么socket.isClosed()返回 false 然后当我尝试通过socket.getOutputStream();方法第二次获得OutputStream类的新实例时，即使我使用 NOT 关闭的相同套接字对象，这也会失败。并且返回消息为SocketException() --> "Socket is closed"

有谁知道它的原因？只有在socket.close();返回 true

之后调用socket.isClosed();方法后，才尝试使用其他组合

即使socket.isClosed（）返回false，Socket getOutputStream方法也会抛出SocketException（＆＃34; Socket关闭＆＃34;）

0 个答案: