java.net.SocketException：套接字已關閉TCP連接

Question

做了一些調試，我認爲這個錯誤發生在下面的這個方法中。該方法基本上向服務器發送一個ID（字符串），服務器在收到該ID後查找它發送回客戶端的記錄。這些ID顯示在用戶選擇的GUI JList中，因此每次用戶在JList中單擊不同的ID時，該方法都由ListSelectionListener事件激活。客戶端從服務器接收到記錄後，將其顯示在JTextField中。當用戶第一次點擊JList中的一個ID時，一切都按預期工作。但是，當您單擊列表中的另一條記錄，我得到異常：

java.net.SocketException: Socket is closed

編輯：現在我越來越：

java.net.SocketException: Software caused connection abort: recv failed

客戶端程序：

import java.awt.BorderLayout; 
import java.awt.Dimension; 
import java.io.IOException; 
import java.io.ObjectInputStream; 
import java.io.ObjectOutputStream; 
import java.net.Socket; 
import java.net.UnknownHostException; 
import java.util.ArrayList; 

import javax.swing.DefaultListModel; 
import javax.swing.JFrame; 
import javax.swing.JList; 
import javax.swing.JPanel; 
import javax.swing.JScrollPane; 
import javax.swing.JTextField; 
import javax.swing.event.ListSelectionEvent; 
import javax.swing.event.ListSelectionListener; 


public class ClientGUI extends JFrame implements ListSelectionListener{ 

    //gui components 
    JList jlist = null; 
    String requestID = null; //Assigned to selected ID in JList. 
    JScrollPane scpane = null; 
    JTextField field = null; 
    JPanel pane = null; 
    DefaultListModel<String> listModel = null; 
    ArrayList<String> idList = null; 

    //client stuff: 
    Socket sock1 = null; 
    Socket sock2 = null; 
    ObjectInputStream in = null; 
    ObjectOutputStream out = null; 

    public ClientGUI() throws ClassNotFoundException{ 
     //get List of IDs from Server1 
     try{ 
      sock1 = new Socket("FahadAhmed-PC", 8889); 
      in = new ObjectInputStream(sock1.getInputStream()); 
      idList = new ArrayList<String>(29); 
      ArrayList<Customer> custList = null; 
      custList = (ArrayList<Customer>) in.readObject(); 
      for(Customer c : custList){ 
       idList.add(c.getID()); 
      } 

      in.close(); 
      sock1.close(); 

      sock2 = new Socket("FahadAhmed-PC", 8888); 
      ArrayList streams = new ArrayList(3); 
      streams.add(out = new ObjectOutputStream(sock2.getOutputStream())); 
      streams.add(in = new ObjectInputStream(sock2.getInputStream())); 

     }catch(UnknownHostException e) { 
      System.err.println("Don't know about host: FahadAhmed-PC"); 
      System.exit(1); 
     }catch(IOException e){ 
      System.err.println(e); 
      System.exit(1); 
     } 

     //Setup GUI 
     jlist = new JList(idList.toArray()); 
     jlist.setVisibleRowCount(10); 
     scpane = new JScrollPane(jlist); 
     jlist.addListSelectionListener(this); 
     pane = new JPanel(new BorderLayout()); 
     pane.setPreferredSize(new Dimension(300, 300)); 
     field = new JTextField(29); 
     field.setEditable(false); 
     pane.add(scpane, BorderLayout.PAGE_START); 
     pane.add(field, BorderLayout.PAGE_END); 

     this.setContentPane(pane); 
     this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
     this.pack(); 
     this.setVisible(true); 
    } 

    public static void main(String args[]) throws ClassNotFoundException{ 
     ClientGUI gui = new ClientGUI(); 
    } 


    @Override 
    public void valueChanged(ListSelectionEvent arg0) { 
     if(!arg0.getValueIsAdjusting()) 
      try { 
       System.out.println(jlist.getSelectedValue().toString()); 
       getRecord(jlist.getSelectedValue().toString()); 
      } catch (ClassNotFoundException e) { 
       // TODO Auto-generated catch block 
       e.printStackTrace(); 
      }  
    } 

    private void getRecord(String getID) throws ClassNotFoundException { 
     try{ 

      //System.out.println(getID + "sent to getRecord method"); 
      out.writeObject(getID); 

      String rec = (String) in.readObject(); 

      field.setText(rec); 
      //in.close(); 
      //sock2.shutdownInput(); 
      out.flush(); 
      //sock2.shutdownOutput(); 
      //out.close(); 

     }catch(UnknownHostException e) { 
      System.err.println("Don't know about host: FahadAhmed-PC"); 
      System.exit(1); 
     }catch(IOException e){ 
      System.err.println(e); 
      System.exit(1); 
     } 
    } 


} 

Answer 1

關閉輸入/輸出流會關閉套接字。您需要使用shutdownInput方法上的插座，關閉只需輸入流：

//do sth with fromSocket ... and close it 
socket.shutdownInput(); 
socket.shutdownOutput(); 

Answer 2

地封閉輸入流或輸出流關閉套接字，我不知道爲什麼你在這裏收什麼，但這裏還有另一個問題。您必須在插座的兩端使用相同的ObjectInputStream和ObjectOutputStream。否則，兩個同伴會失去同步，你會開始看到像StreamCorruptedException: invalid type code這樣的東西。