java小程序套接字连接问题

Question

我用于套接字通信的代码在命令提示符下运行的程序中工作，但是当在嵌入网页的小程序中使用相同的代码时，会出现安全问题。它不连接... 请帮帮我，需要在3天内完成这个...... 服务器：

    public void run()
{
    try
    {
        ServerSocket s1 = new ServerSocket(5555); // create a server socket and bind it to port number.

        Socket s2 = s1.accept(); // make the server listen for a connection.

        DataInputStream in = new DataInputStream(s2.getInputStream());
        PrintStream out = new PrintStream(s2.getOutputStream());
        while(true)
        {
            char[] buf = new char[150];
            String line = in.readUTF(); // wait for the client to send a line of text.
            if(line.equals("send"))
            {
                for(int i=0;i<150;i++)
                    buf[i]=0;
                if(Traffic1.s1wiut) buf[0]='1';
                if(Traffic1.s1wist) buf[1]='1';
                if(Traffic1.s1wirt) buf[2]='1';
                if(Traffic1.s1silt) buf[3]='1';
                if(Traffic1.s1siut) buf[4]='1';
                if(Traffic1.s1sirt) buf[5]='1';
            }
            String line1 = new String(buf);
            out.println(line1); // send the data to the client.
            out.flush(); // flush the stream to ensure that the data reaches the other end.
        }
    }

客户端：

    public void run()
{

    while(true)
    {
        int serverPort = 5555; // port number on which the server is listening.

        try
        {
            InetAddress ipAddress = InetAddress.getLocalHost(); // create an object that represents the above IP address.

            Socket socket = new Socket(ipAddress,serverPort); // create a socket with the server's IP address and server's port.

            DataInputStream in = new DataInputStream(socket.getInputStream());
            PrintStream out = new PrintStream(socket.getOutputStream());

            while(true)
            {
                char[] buf = new char[150];
                String line = "send"; // request string to send to server.
                out.println(line); // send the above line to the server.
                out.flush(); // flush the stream to ensure that the data reaches the other end.
                line = in.readUTF(); // wait for the server to send a line of text.
                buf = line.toCharArray();
                if(buf[0]=='1')     s1wiut=true;    else    s1wiut=false;
                if(buf[1]=='1')     s1wist=true;    else    s1wist=false;
                if(buf[2]=='1')     s1wirt=true;    else    s1wirt=false;
                if(buf[3]=='1')     s1silt=true;    else    s1silt=false;
                if(buf[4]=='1')     s1siut=true;    else    s1siut=false;
                if(buf[5]=='1')     s1sirt=true;    else    s1sirt=false;

                repaint();
                Thread.sleep(1000);
            }
        }

有什么办法可以解决这个问题？？

Answer 1

1. 未签名的小程序只能连接到加载它的主机。

2. 您的小程序尝试连接到“localhost”。所以服务器也必须在 localhost 上运行。是吗？你是怎么安排的？

3. 您使用readUTF() 读取，但println() 写入。那是行不通的。 println() 需要readLine()，readUTF() 需要writeUTF()。

Answer 2

您能发布您遇到的错误类型吗？即使它也是与安全相关的问题

一个小建议：

我认为您需要按如下方式更改您的服务器代码（因为服务器总是监听客户端套接字的接受）

public void run()
{
    try
    {
        ServerSocket s1 = new ServerSocket(5555); // create a server socket and bind it to port number.

        while(true){

        Socket s2 = s1.accept(); // make the server listen for a connection.

        DataInputStream in = new DataInputStream(s2.getInputStream());
        PrintStream out = new PrintStream(s2.getOutputStream());
        while(true)
        {
            char[] buf = new char[150];
            String line = in.readUTF(); // wait for the client to send a line of text.
            if(line.equals("send"))
            {
                for(int i=0;i<150;i++)
                    buf[i]=0;
                if(Traffic1.s1wiut) buf[0]='1';
                if(Traffic1.s1wist) buf[1]='1';
                if(Traffic1.s1wirt) buf[2]='1';
                if(Traffic1.s1silt) buf[3]='1';
                if(Traffic1.s1siut) buf[4]='1';
                if(Traffic1.s1sirt) buf[5]='1';
            }
            String line1 = new String(buf);
            out.println(line1); // send the data to the client.
            out.flush(); // flush the stream to ensure that the data reaches the other end.
          }
       } // end of while
    }

你的客户如下所示

public void run()
{

    int serverPort = 5555; // port number on which the server is listening.

    try
    {
        InetAddress ipAddress = InetAddress.getLocalHost(); // create an object that represents the above IP address.

        Socket socket = new Socket(ipAddress,serverPort); // create a socket with the server's IP address and server's port.

        DataInputStream in = new DataInputStream(socket.getInputStream());
        PrintStream out = new PrintStream(socket.getOutputStream());

        while(true)
        {
            char[] buf = new char[150];
            String line = "send"; // request string to send to server.
            out.println(line); // send the above line to the server.
            out.flush(); // flush the stream to ensure that the data reaches the other end.
            line = in.readUTF(); // wait for the server to send a line of text.
            buf = line.toCharArray();
            if(buf[0]=='1')     s1wiut=true;    else    s1wiut=false;
            if(buf[1]=='1')     s1wist=true;    else    s1wist=false;
            if(buf[2]=='1')     s1wirt=true;    else    s1wirt=false;
            if(buf[3]=='1')     s1silt=true;    else    s1silt=false;
            if(buf[4]=='1')     s1siut=true;    else    s1siut=false;
            if(buf[5]=='1')     s1sirt=true;    else    s1sirt=false;

            repaint();
            Thread.sleep(1000);
        }
    }catch(Exception e){
    }