Sockets java - Beginner

Question

Sockets java - Beginner

Navigation

#1 by (1 votes)

3

I'm starting in java and I have a problem with sockets, I wanted my server to receive a value and then I wanted to turn it into a String so I could include it in if conditions. However, despite the server receiving the text without problem, I can not pass the value to a String .

Follow the server code:

/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package javasockets;

import java.io.DataInputStream;
import java.io.IOException;
import static java.lang.System.exit;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Scanner;

/**
 *
 * @author Nuno
 */
public class JavaSockets {

    public static String T = "s";

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws IOException {
        // TODO code application logic here
        try {
            ServerSocket sckServer = new ServerSocket(5000);

            System.out.println("Porta 5000 aberta!");
            Socket sck;

            while (true) {

                sck = sckServer.accept();
                try (Scanner entrada = new Scanner(sck.getInputStream())) {

                    while (entrada.hasNextLine()) {

                        System.out.println(entrada.nextLine());
                    }
                    String texto = entrada.nextLine();
                    System.out.println("ola" + texto);
                    String fnames = texto;
                    System.out.println("ola" + fnames);
                    System.out.println(texto);
                    if (texto.equals(T)) {
                        System.out.println("LOOL");
                    }
                }
                sckServer.close();
            }

        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

The following is the client code:

/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package javasockets;

import java.io.IOException;
import java.io.PrintStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.Scanner;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 *
 * @author Nuno
 */
public class cliente {

    public static void main(String[] args) throws IOException {
        while (true) {
            Socket cliente = new Socket("127.0.0.1", 5000);
            System.out.println("O cliente se conectou ao servidor!");

            Scanner teclado = new Scanner(System.in);
            PrintStream saida = new PrintStream(cliente.getOutputStream());

            while (teclado.hasNextLine()) {
                saida.println(teclado.nextLine());
            }
            saida.flush();
            saida.close();
            teclado.close();
        }

    }

    static Object getInetAddress() {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }
}

java socket

asked by anonymous 18.02.2015 / 23:09

1 answer

How to organize css and js? How do I update a row in the datatable with jquery? [closed]

score 1 · Answer 1

It is not clear when you say you receive the text but can not pass it to a String. Reception is already a String.

I think your problem might be on your server at this point:

                while (entrada.hasNextLine()) {

                    System.out.println(entrada.nextLine());
                }
                String texto = entrada.nextLine();

You are consuming the entire entry in while and only displaying it, and of course the while will end when there is nothing else to consume ( hasNextLine() ), then after while you simply pass nothing for String texto .

Try this:

                String texto = "";

                while (entrada.hasNextLine()) {
                    texto += entrada.nextLine() + "\n";
                }

                System.out.println(texto);

You save all the content before into a variable and then show it. Note the inclusion of the \n line escape, this causes ln of println . Then you can do whatever you want with texto .