java - 输入套接字意外关闭时吞下 IOException

Question

当套接字意外关闭时，此代码段失败。不IOException 被抛出，并且 s.read() 永远不会返回。

  try {
   while (!doneReading)
   {    /* read blocks waiting for data */
    int readResult = s.read(inBuf, inBufLength, 1);
    ...
   }
  }
  catch (IOException err) { .. }

当socket初始关闭时，栈如下:

    Thread [Thread-10] (Suspended (exception SocketException))  
        SocketInputStream.socketRead0(FileDescriptor, byte[], int, int, int) line: not available [native method]    
        SocketInputStream.read(byte[], int, int, int) line: 150 
        SocketInputStream.read(byte[], int, int) line: 121  
        SocketInputStream.read(byte[]) line: 107    
        JavaSEPort$SocketImpl.readFromStream() line: 7462   
        JavaSEPort.readFromSocketStream(Object) line: 7601  
        Socket$SocketInputStream.read(byte[], int, int) line: 179   
        NetConn.runRead() line: 1044    
        NetConn.run() line: 989 
        Thread.run() line: 744  
C:\java\jdk1.8.0\bin\javaw.exe (Dec 23, 2015, 4:47:53 PM)   

socketexception 显然被捕获，并作为 ioexception 重新抛出此时:

    Thread [Thread-10] (Suspended (exception IOException))  
        owns: DualStackPlainSocketImpl  (id=93) 
        DualStackPlainSocketImpl(AbstractPlainSocketImpl).available() line: 465 [local variables unavailable]   
        SocketInputStream.available() line: 238 
        JavaSEPort$SocketImpl.getAvailableInput() line: 7428    
        JavaSEPort$SocketImpl.readFromStream() line: 7452   
        JavaSEPort.readFromSocketStream(Object) line: 7601  
        Socket$SocketInputStream.read(byte[], int, int) line: 179   
        NetConn.runRead() line: 1044    
        NetConn.run() line: 989 
        Thread.run() line: 744  

        NetConn.run() line: 989 
        Thread.run() line: 744  

很难详细说明发生了什么，因为 JavaSEPort 的源未绑定(bind)在eclipse环境下

更多信息:我获取了更多资源，可以看到 JavaSEPort.readFromStream 捕获 IOException 并返回 null。再往上几层，在 Socket.read 中有一个 while (buffer==null) 永远不会被转义。这完全解释了这种行为 - 我看到一个无限循环的堆栈跟踪并且读取永远不会返回。

Answer 1

当出现错误时，您应该得到 connectionError 回调而不是异常。