Praktek Client-Server: Membuat Aplikasi Client Server Sederhana Berbasis Java

Buatlah sebuah project aplikasi di Netbeans atau di eclipse (tergantung anda) dengan Source Code untuk Server adalah sbb:

package client_server;

/**

*

* @author samsul

*/

import java.io.IOException;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

import java.net.ServerSocket;

import java.net.Socket;

import java.util.logging.Level;

import java.util.logging.Logger;

public class Client_Server {

/**

* @param args the command line arguments

*/

public static void main(String[] args) {

// TODO code application logic here

try{

//inisial objek server soket denga meset port 51111

ServerSocket ss = new ServerSocket(5111);

Socket s;

String balasan;

String balasan2;

//inisialisasi objek input dan ouput stream

ObjectInputStream in = null;

ObjectOutputStream out = null;

//fungsi bawaan dari class server sket yang mereturn objek soket

//tanda clent server terhubung

s = ss.accept();

//alokasi memori objek

out = new ObjectOutputStream(s.getOutputStream());

//fungsi bawaan objek output stream untuk membersihkan isi memory

out.flush();

//alokasi memory

in = new ObjectInputStream(s.getInputStream());

balasan = “”;

balasan2 = “”;

while (true) {

balasan = “”;

balasan2 = “”;

balasan=ReadMassage(in);

//program akan berhenti sampai input exit dari klien

if(balasan.equals(“exit”)) break;

else {

if(balasan.equals(“ini client”)) {

SendMassage(“ini server, masukan username”, out);

balasan2 = ReadMassage(in);

if(balasan2.equals(“admin”)) SendMassage(“Selamat datang admin”, out);

else

{

if (balasan2.equals(“user”)) SendMassage(“Selamat datang user”, out);

else SendMassage(“username tidak diketahui”, out);

}

} else {

SendMassage(“perintah tidak diketahui”, out);

}

}

}

//Menutup semua stream

in.close();

out.close();

s.close();

ss.close();

} catch (IOException ex) {

Logger.getLogger(Client_Server.class.getName()).log(Level.SEVERE, null, ex);

}

}

//fungsi membaca input dari client

public static String ReadMassage(ObjectInputStream in)

{

String reader = “”;

try {

reader=(String) in.readObject();

} catch (IOException ex) {

Logger.getLogger(Client_Server.class.getName()).log(Level.SEVERE, null, ex);

} catch (ClassNotFoundException ex) {

Logger.getLogger(Client_Server.class.getName()).log(Level.SEVERE, null, ex);

}

System.out.println(reader);

//mereturn nilai string hasil bacaan

return reader;

}

//Fungsi untuk mengirim objek /data ke klient

public static void SendMassage(String word, ObjectOutputStream out)

{

try {

out.writeObject(word);

//bersihkan memori

out.flush();

} catch (IOException ex) {

Logger.getLogger(Client_Server.class.getName()).log(Level.SEVERE, null, ex);

}

}

}

Apabila anda sudah membuat aplikasi servernya maka anda tinggal membuat aplikasi clientnya, maka buat projek baru di netbeans atau eclipse (terserah anda inigi pilih yang mana, hehe), dengan source code sebagai berikut:

package client;

import java.util.Scanner;

import java.io.IOException;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

import java.net.Socket;

import java.util.logging.Level;

import java.util.logging.Logger;

/**

*

* @author dodi

*/

public class Client {

/**

* @param args the command line arguments

*/

public static void main(String[] args) throws IOException {

// TODO code application logic here

Socket s = new Socket(“localhost”,5111);

ObjectInputStream in = null;

ObjectOutputStream out = null;

Scanner scanf = new Scanner(System.in);

String input=”";

String balasan;

String balasan2;

out=new ObjectOutputStream(s.getOutputStream());

out.flush();

in=new ObjectInputStream(s.getInputStream());

balasan=”";

balasan2=”";

while(true)

{

balasan=”";

balasan2=”";

input = scanf.nextLine();

SendMessage(input,out);

if(input.equals(“exit”))break;

else

{

balasan=ReadMessage(in);

if(balasan.equals(“ini server, masukkan username”))

{

input=scanf.nextLine();

SendMessage(input,out);

balasan2=ReadMessage(in);

}

}

}

in.close();

out.close();

s.close();

}

public static void SendMessage(String word, ObjectOutputStream out)

{

try{

out.writeObject(word);

out.flush();

}catch(IOException ex){

Logger.getLogger(Client.class.getName()).log(Level.SEVERE,null,ex);

}

}

public static String ReadMessage(ObjectInputStream in)

{

String reader=”";

try{

reader=(String)in.readObject();

}catch(IOException ex){

Logger.getLogger(Client.class.getName()).log(Level.SEVERE, null,ex);

}catch(ClassNotFoundException ex){

Logger.getLogger(Client.class.getName()).log(Level.SEVERE, null,ex);

}

System.out.println(reader);

return reader;

}

}

Setelah anda berhasil membuat aplikasi server dan clientnya, langsung saja anda running kedua aplikasi tersebut, berikut aplikasi server yang sedang running, dan statusnya listen.