Question

我编写了一个java TCP服务器程序。我将在我的电脑上运行该程序。我已经编写了一个java TCP客户端程序，我将在android模拟器上运行。我将使用ip地址10.0.2.2连接到服务器，因为我使用的是Android模拟器。但表现非常糟糕。服务器在接近8-10分钟后接收客户端发送的数据。并且模拟器没有从服务器接收任何数据。请看哪里出错了？

TCP服务器（在PC上运行）：

import java.io.*;
import java.net.*;

class TCPServer
{
   public static void main(String argv[]) throws Exception
      {
         String clientSentence;
         String capitalizedSentence=null;
         ServerSocket welcomeSocket = new ServerSocket(9000);

         while(true)
         {
            Socket connectionSocket = welcomeSocket.accept();
            BufferedReader inFromClient =new BufferedReader(new InputStreamReader(connectionSocket.getInputStream()));
            DataOutputStream outToClient = new DataOutputStream(connectionSocket.getOutputStream());
            clientSentence = inFromClient.readLine();
            System.out.println("Received: " + clientSentence);
            if(clientSentence.equals("IS COMPUTER ON?"))
            {
                capitalizedSentence = "YES SYSTEM IS ON.";
            }
            outToClient.writeBytes(capitalizedSentence);
         }
      }
}

TCP客户端（运行在ANDROID EMULATOR中）：

package a.b.c;
import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.InputStreamReader;
import java.net.Socket;
import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;

public class WifitestActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        try
        {
            String sentence="IS COMPUTER ON?";
            String modifiedSentence=sentence;
            Socket clientSocket = new Socket("10.0.2.2", 9000);
            DataOutputStream outToServer = new DataOutputStream(clientSocket.getOutputStream());
            BufferedReader inFromServer = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
            outToServer.writeBytes(sentence);
            modifiedSentence = inFromServer.readLine();
            TextView a=(TextView)findViewById(R.id.textView1);
            a.setText(modifiedSentence);
            a.showContextMenu();
            clientSocket.close();
        }
        catch(Exception e)
        {
            TextView a=(TextView)findViewById(R.id.textView1);
            a.setText(e.toString());
            a.showContextMenu();
        }

    }
}

Answer 1

您可以查看模拟器的network delay option吗？您也可以看到机器上运行的进程不多，因为这些进程可能会窃取您希望仿真器使用的CPU周期

Answer 2

几点提示

要创建客户端套接字，请使用以下

构造函数Socket(String host, int port)可以无限期地阻塞，直到建立与主机的初始连接。

您可以通过首先构建一个未连接的套接字，然后将其与超时连接来解决此问题：

Socket s = new Socket();
s.connect(new InetSocketAddress(host, port), timeout);

在服务器端使用PrintWriter，因为它将作为套接字和字符数据的低级别字节之间的桥接器。

例如：服务器代码

public class ServerTest {

ServerSocket s;

public void go() {

    try {
        s = new ServerSocket(44457);

        while (true) {

            Socket incoming = s.accept();
            Thread t = new Thread(new MyCon(incoming));
            t.start();
        }
    } catch (IOException e) {

        e.printStackTrace();
    }

}

class MyCon implements Runnable {

    Socket incoming;

    public MyCon(Socket incoming) {

        this.incoming = incoming;
    }

    @Override
    public void run() {

        try {
            PrintWriter pw = new PrintWriter(incoming.getOutputStream(),
                    true);
            InputStreamReader isr = new InputStreamReader(
                    incoming.getInputStream());
            BufferedReader br = new BufferedReader(isr);
            String inp = null;

            boolean isDone = true;

            System.out.println("TYPE : BYE");
            System.out.println();
            while (isDone && ((inp = br.readLine()) != null)) {

                System.out.println(inp);
                if (inp.trim().equals("BYE")) {
                    System.out
                            .println("THANKS FOR CONNECTING...Bye for now");
                    isDone = false;
                    s.close();
                }

            }
        } catch (IOException e) {
            // TODO Auto-generated catch block
            try {
                s.close();
            } catch (IOException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
            e.printStackTrace();
        }

    }

}

public static void main(String[] args) {

    new ServerTest().go();

}

}

使用android和PC的TCP客户端和服务器程序的性能问题

2 个答案: