套接字例外：套接字已關閉

Question

我想創建能夠與多個客戶端連接的服務器。 我的主要功能是：

ServerSocket serverSocket = null; 
    try { 
     serverSocket = new ServerSocket(5556); 
    } catch (IOException ex) { 
     Logger.getLogger(MakaoServer.class.getName()).log(Level.SEVERE, null, ex); 
    } 
    while (true) { 
     try { 
      Socket connection = serverSocket.accept(); 
      PlayerConnection playerConn = new PlayerConnection(connection); 
      playerConn.start(); 
     } catch (IOException ex) { 
      System.out.println("Nie można było utworzyć gniazda."); 
     } 
    } 

PlayerConnection是一個Thread類。 run方法：

public void run() { 
    InputStream input = null; 
    while (true) { 
     try { 
      input = connection.getInputStream(); 
      BufferedReader reader = new BufferedReader(new InputStreamReader(input)); 
      String msg = reader.readLine(); 
      System.out.println(msg); 

     } catch (IOException ex) { 
      Logger.getLogger(PlayerConnection.class.getName()).log(Level.SEVERE, null, ex); 
     } finally { 

     } 
    } 
} 

當我運行客戶端和發送消息給它接收的服務器，但是，接下來將在循環迭代connection.getInputStream（）;拋出一個Socket異常套接字被關閉。爲什麼？

java.net.SocketException: socket closed 
at java.net.SocketInputStream.socketRead0(Native Method) 
at java.net.SocketInputStream.read(SocketInputStream.java:150) 
at java.net.SocketInputStream.read(SocketInputStream.java:121) 
at sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:283) 
at sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:325) 
at sun.nio.cs.StreamDecoder.read(StreamDecoder.java:177) 
at java.io.InputStreamReader.read(InputStreamReader.java:184) 
at java.io.BufferedReader.fill(BufferedReader.java:154) 
at java.io.BufferedReader.readLine(BufferedReader.java:317) 
at java.io.BufferedReader.readLine(BufferedReader.java:382) 
at makaoserver.PlayerConnection.run(PlayerConnection.java:38) 

Answer 1

將輸入流和緩衝讀取器放在循環之外。

可能創建多個流連接到相同的輸入流造成這種情況。

Answer 2

嘗試

public void run() { 
    InputStream input = null; 
    input = connection.getInputStream(); 
    BufferedReader reader = new BufferedReader(new InputStreamReader(input)); 

    while (true) { 
     try { 
      String msg = reader.readLine(); 
      System.out.println(msg); 
     } catch (IOException ex) { 
      Logger.getLogger(PlayerConnection.class.getName()).log(Level.SEVERE, null, ex); 
     } finally { 

     } 
    } 
} 

另外不要忘記關閉插座，當你與他們做

try { 
    // Create objects 
    // do stuff 
} finally { 
    if (obj != null) obj.close(); 
}