java - 返回 Java TCP Socket 编程中的 N 协议实现

Question

我正在尝试使用 Java TCP 套接字实现 Go Back N ARQ 协议。但我得到数组越界错误。我在下面附上了我的服务器端和客户端代码。这是服务器程序：

import java.net.*;
import java.io.*;
import java.util.*;
public class Server
{
public static void main(String args[]) throws Exception
{
    ServerSocket server=new ServerSocket(6262);
    System.out.println("Server established.");
    Socket client=server.accept();
    ObjectOutputStream oos=new ObjectOutputStream(client.getOutputStream());
    ObjectInputStream ois=new ObjectInputStream(client.getInputStream());
    System.out.println("Client is now connected.");
    int x=(Integer)ois.readObject();
    int k=(Integer)ois.readObject();
    int j=0;
    int i=(Integer)ois.readObject();
    boolean flag=true;
    Random r=new Random(6);
    int mod=r.nextInt(6);
    while(mod==1||mod==0)
        mod=r.nextInt(6);
    while(true)
    {
        int c=k;
        for(int h=0;h<=x;h++)
        {
            System.out.print(" "+c+" ");
            c=(c+1)%x;
        }
        System.out.println();
        System.out.println();
        if(k==j)
        {
            System.out.println("Frame "+k+" recieved"+"\n"+"Data:"+j);
            j++;
            System.out.println();
        }
        else
            System.out.println("Frames recieved not in correct order"+"\n"+" Expected farme:" + j +"\n"+ " Recieved frame no :"+ k);
        System.out.println();
        if(j%mod==0 && flag)
        {
            System.out.println("Error found. Acknowledgement not sent. ");
            flag=!flag;
            j--;
        }
        else if(k==j-1)
        {
            oos.writeObject(k);
            System.out.println("Acknowledgement sent");
        }
        System.out.println();
        if(j%mod==0)
            flag=!flag;
        k=(Integer)ois.readObject();
        if(k==-1)
            break;
        i=(Integer)ois.readObject();
    }
        System.out.println("Client finished sending data. Exiting");
        oos.writeObject(-1);
    }
}

这是客户端程序：

import java.util.*;
import java.net.*;
import java.io.*;
public class Client
{
public static void main(String args[]) throws Exception
{
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        System.out.print("Enter the value of m : ");
        int m=Integer.parseInt(br.readLine());
        int x=(int)((Math.pow(2,m))-1);
        System.out.print("Enter no. of frames to be sent:");
        int count=Integer.parseInt(br.readLine());
        int data[]=new int[count];
        int h=0;
        for(int i=0;i<count;i++)
        {
            System.out.print("Enter data for frame no " +h+ " => ");
            data[i]=Integer.parseInt(br.readLine());
            h= (h+1)%x;
        }
        Socket client=new Socket("localhost",6262);
        ObjectInputStream ois=new ObjectInputStream(client.getInputStream());
        ObjectOutputStream oos=new ObjectOutputStream(client.getOutputStream());
        System.out.println("Connected with server.");
        boolean flag=false;
        GoBackNListener listener=new GoBackNListener(ois,x);
        listener=new GoBackNListener(ois,x);
        listener.t.start();
        int strt=0;
        //h=0;
        oos.writeObject(x);
        do
        {
            int c=h;
            for(int i=h;i<count;i++)
            {
                System.out.print(" "+c+" ");
                c=(c+1)%x;
            }
            System.out.println();
            System.out.println();
            h=strt;
            for(int i=strt;i<x;i++)
            {
                try
                {
                    System.out.println("Sending frame:"+ h);
                    h= (h + 1) % x;
                    System.out.println();
                    oos.writeObject(i);
                    oos.writeObject(data[i]);
                    Thread.sleep(1000);
                }
                catch(Exception e)
                {
                    System.out.println("Exception " + e);
                }
            }
            listener.t.join(3500);
            if(listener.reply!=x-1)
            {
                System.out.println("No reply from server in 3.5 seconds. Resending data from frame no " + (listener.reply+1));
                System.out.println();
                strt=listener.reply+1;
                flag=false;
            }
            else
            {
                System.out.println("All elements sent successfully. Exiting");
                flag=true;
            }
        }while(!flag);
        oos.writeObject(-1);
    }
}

class GoBackNListener implements Runnable
{
    Thread t;
    ObjectInputStream ois;
    int reply,x;
    GoBackNListener(ObjectInputStream o,int i)
    {
        t=new Thread(this);
        ois=o;
        reply=-2;
        x=i;
    }
    @Override
    public void run() {
        try
        {
            int temp=0;
            while(reply!=-1)
            {
                reply=(Integer)ois.readObject();
                if(reply!=-1 && reply!=temp+1)
                    reply=temp;
                if(reply!=-1)
                {
                    temp=reply;
                    System.out.println("Acknowledgement of frame no " + (reply%x) + " recieved.");
                    System.out.println();
                }
            }
            reply=temp;
        }
        catch(Exception e)
        {
            System.out.println("Exception => " + e);
        }
    }
}

我得到数组索引越界错误

oos.writeObject(i);
oos.writeObject(data[i]);

有人可以帮我弄这个吗？