Android和Java服务器之间的套接字编程问题

Question

我遇到的问题是我能够正确连接，但是该死的连接不会关闭！ 我必须做什么？

服务器端 ：

听.java

package com.example.ServerSide;


import java.net.ServerSocket;

public class Listen extends servVars {

    public static void main(String[] args) {
        try {
            System.out.println("HOSTED");
            hostAt = new ServerSocket(2051);
            conDev = hostAt.accept();
            System.out.println(conDev.getInetAddress()+":"+conDev.getPort());
            for(;;) {
                System.out.print(".");
                Thread.sleep(1000);
                if(conDev.isClosed())
                    break;
            }
        } catch(Exception E) {

        }
    }

}

servVars.java

package com.example.ServerSide;

import java.net.ServerSocket;
import java.net.Socket;

public class servVars {
    static ServerSocket hostAt;
    static Socket conDev;
}

客户端 ：

* Connect_to_server.java *

package com.example.clientside;

import java.net.Socket;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class Connect_to_server extends Activity implements View.OnClickListener {

    private EditText IP_field;
    private EditText port_field;
    private String IP;
    private String portStr;
    private int port;
    public static Socket conn;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.connect_to_server);
        IP_field = (EditText) this.findViewById(R.id.IP_field);
        port_field = (EditText) this.findViewById(R.id.port_field);
        Button connect = (Button) this.findViewById(R.id.connect_button);
        connect.setOnClickListener(this);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.connect_to_server, menu);
        return true;
    }

    @Override
    public void onClick(View v) {
        IP = IP_field.getText().toString();
        portStr = port_field.getText().toString();
        Toast.makeText(getApplicationContext(),"Trying to connect to "+IP+":"+portStr,Toast.LENGTH_SHORT).show();
        try {
            port = Integer.parseInt(portStr);
            conn = new Socket(IP, port);
            Intent landing = new Intent(this, Landing.class);
            startActivity(landing);
        } catch(Exception E) {
            Intent failure = new Intent(this, ConnectFail.class);
            failure.putExtra("ctsException", E.toString());
            startActivity(failure);
        }
    }

}

Landing.java

package com.example.clientside;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

public class Landing extends Activity implements View.OnClickListener {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.landing);
        Button disconnect = (Button) this.findViewById(R.id.disconnect_button);
        disconnect.setOnClickListener(this);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.landing, menu);
        return true;
    }

    @Override
    public void onClick(View v) {
        try {
            Connect_to_server.conn.close();
            Toast.makeText(getApplicationContext(),"Disconnected!",Toast.LENGTH_SHORT).show();
        } catch(Exception E) {}
    }

}

我认为我没有发布布局和ConnectFail.java，因为这不是必需的。

编辑：我猜这与Socket和ServerSocket是静态的有关。 但是，我不知道如何使它们变为非静态并仍然使程序运行！

Answer 1

isClosed()告诉您是否已经关闭了套接字。 它不会告诉您有关连接状态的任何信息。 如果对等方关闭套接字，则在读取以下内容时会收到EOF指示：

• read()返回-1
• readLine()返回null
• readXXX()会为任何其他XXX抛出EOFException 。

由于您的服务器未从客户端读取任何内容，因此它可能无法发现客户端何时关闭连接。