Dalam tulisan ini akan membahas tentang aplikasi chat sederhana menggunakan bahasa pemrograman java. Aplikasi ini akan mengimplementasikan Class ServerSocket dan Class Socket, dikembangkan dengan NetBeans 7.2
Hasil tampilan dari aplikasi ini adalah seperti gambar di bawah ini
Tampilan ChatServer ketika sedang dijalankan
Tampilan Chat Client ketika sedang dijalankan
Pertama buat ChatServer.java
package com.andik.chatserver;
import java.io.*;
import java.net.*;
import java.util.*;
public class ChatServer {
private static int uniqueId;
private ArrayList<ChatServer.ClientThread> clients;
private int port;
private boolean keepGoing;
public ChatServer() {
this.port = 9999;
clients = new ArrayList<>();
}
public void start() {
keepGoing = true;
try {
ServerSocket serverSocket = new ServerSocket(port);
while (keepGoing) {
System.out.println("ChatServer waiting for Clients on port " + port + ".");
Socket socket = serverSocket.accept();
if (!keepGoing) {
break;
}
ChatServer.ClientThread t = new ChatServer.ClientThread(socket);
clients.add(t);
t.start();
send("login~" + t.username + "~" + t.username + " sedang login...~Server~\n");
}
try {
serverSocket.close();
for (int i = 0; i < clients.size(); ++i) {
ChatServer.ClientThread tc = clients.get(i);
try {
tc.sInput.close();
tc.sOutput.close();
tc.socket.close();
} catch (IOException ioE) {
}
}
} catch (Exception e) {
System.out.println("Exception closing the server and clients: " + e);
}
} catch (IOException e) {
String msg = "Exception on new ServerSocket: " + e + "\n";
System.out.println(msg);
}
}
private synchronized void send(String message) {
for (int i = clients.size(); --i >= 0;) {
ChatServer.ClientThread ct = clients.get(i);
if (!ct.writeMsg(message)) {
clients.remove(i);
System.out.println("Disconnected Client " + ct.username + " removed from list.");
}
}
}
private String getClients() {
String s = "";
for (ClientThread clientThread : clients) {
s += clientThread.username + ":";
}
s += "---";
System.out.println(s);
return s;
}
private synchronized void remove(int id) {
for (int i = 0; i < clients.size(); ++i) {
ChatServer.ClientThread ct = clients.get(i);
if (ct.id == id) {
clients.remove(i);
return;
}
}
}
public static void main(String[] args) {
ChatServer server = new ChatServer();
server.start();
}
private class ClientThread extends Thread {
private Socket socket;
private ObjectInputStream sInput;
private ObjectOutputStream sOutput;
private int id;
private String username;
public ClientThread(Socket socket) {
id = ++uniqueId;
this.socket = socket;
System.out.println("Menciptakan Object Input/Output Streams");
try {
sOutput = new ObjectOutputStream(socket.getOutputStream());
sInput = new ObjectInputStream(socket.getInputStream());
String message = (String) sInput.readObject();
username = message.split("~")[1];
System.out.println(username + " masuk.");
} catch (IOException e) {
System.out.println("Exception creating new Input/output Streams: " + e);
} catch (ClassNotFoundException e) {
}
}
@Override
public void run() {
boolean keepGoing = true;
while (keepGoing) {
String message;
try {
message = sInput.readObject().toString();
} catch (IOException e) {
System.out.println(username + " Exception reading Streams: " + e);
break;
} catch (ClassNotFoundException e2) {
break;
}
String type = message.split("~")[0];
String pengirim = message.split("~")[1];
String text = message.split("~")[2];
String kepada = message.split("~")[3];
String response;
switch (type) {
case "postText":
response = "recieveText~" + pengirim + "~" + text + "~" + kepada + "~\n";
send(response);
break;
case "postPrivateText":
response = "recievePrivateText~" + pengirim + "~" + text + "~" + kepada + "~\n";
send(response);
break;
case "login":
response = "login~" + pengirim + "~" + text + "~" + kepada + "~\n";
send(response);
break;
case "logout":
response = "logout~" + pengirim + "~" + text + "~" + kepada + "~\n";
send(response);
break;
case "list":
response = "list~server~" + getClients() + "~ ~ ~ ~ ~\n";
send(response);
break;
}
}
remove(id);
close();
}
private void close() {
try {
if (sOutput != null) {
sOutput.close();
}
} catch (Exception e) {
}
try {
if (sInput != null) {
sInput.close();
}
} catch (Exception e) {
}
try {
if (socket != null) {
socket.close();
}
} catch (Exception e) {
}
}
private boolean writeMsg(String msg) {
if (!socket.isConnected()) {
close();
return false;
}
try {
sOutput.writeObject(msg);
} catch (IOException e) {
System.out.println("Error sending message to " + username);
System.out.println(e.toString());
}
return true;
}
}
}
Ke Dua buat ChatClient.java
ChatClient.java ini merupakan antarmuka untuk client. Caranya adalah, klik menu File/ New File maka akan tampil dialog New File. Pilih Swing GUI Form pada list kategori dan pilih JFrame Form pada list File Types. Klik Next dan beri nama Class dengan ChatClient lalu akhiri dengan menekan tombol Finish
Buat desain seperti gambar di bawah ini
Desain Chat Client
Ubah variable jTextFiel1 menjadi serverTextField, jTextField2 menjadi portTextField, jTextField3 menjadi usernameTextField, jButton1 menjadi masukButton, jTextArea1 menjadi viewTextArea, jTextField4 menjadi postTextField, jButton2 menjadi kirimButton dan jTable1 menjadi clientTable
Jika semua sudah seperti gambar di atas, tinggal masukkan kode nya. Masukkan kode di bawah ini
package com.andik.chatclient;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.table.DefaultTableModel;
/**
*
* @author Andik Hermawan
*/
public class ChatClient extends javax.swing.JFrame {
/**
* Creates new form ChatClient
*/
private ObjectInputStream input;
private ObjectOutputStream output;
private Socket socket;
private String server, username;
private int port;
private List<String> clients;
public ChatClient() {
clients = new ArrayList<>();
initComponents();
}
public boolean start() {
try {
socket = new Socket(server, port);
} catch (Exception ec) {
System.out.println("Error connectiong to server:" + ec);
return false;
}
String msg = "Connection accepted " + socket.getInetAddress() + ":" + socket.getPort();
System.out.println(msg);
try {
input = new ObjectInputStream(socket.getInputStream());
output = new ObjectOutputStream(socket.getOutputStream());
} catch (IOException eIO) {
System.out.println("Exception creating new Input/output Streams: " + eIO);
return false;
}
new ChatClient.ListenFromServer().start();
try {
output.writeObject("login~" + username + "~" + username + " sedang login...~server~\n");
output.writeObject("list~" + username + "~" + username + " sedang login...~server~\n");
} catch (IOException eIO) {
System.out.println("Exception doing login : " + eIO);
disconnect();
return false;
}
return true;
}
private void disconnect() {
try {
// TODO add your handling code here:
output.writeObject("logout~" + username + "~" + username + " sudah logout...~Server~\n");
} catch (IOException ex) {
//Logger.getLogger(ChatClient.class.getName()).log(Level.SEVERE, null, ex);
}
try {
if (input != null) {
input.close();
}
} catch (Exception e) {
}
try {
if (output != null) {
output.close();
}
} catch (Exception e) {
}
try {
if (socket != null) {
socket.close();
}
} catch (Exception e) {
}
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jScrollPane1 = new javax.swing.JScrollPane();
viewTextArea = new javax.swing.JTextArea();
jScrollPane2 = new javax.swing.JScrollPane();
clientTable = new javax.swing.JTable();
postTextField = new javax.swing.JTextField();
kirimButton = new javax.swing.JButton();
jLabel2 = new javax.swing.JLabel();
serverTextField = new javax.swing.JTextField();
jLabel3 = new javax.swing.JLabel();
portTextField = new javax.swing.JTextField();
masukButton = new javax.swing.JButton();
jLabel4 = new javax.swing.JLabel();
usernameTextField = new javax.swing.JTextField();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
viewTextArea.setEditable(false);
viewTextArea.setColumns(20);
viewTextArea.setLineWrap(true);
viewTextArea.setRows(5);
viewTextArea.setFocusable(false);
jScrollPane1.setViewportView(viewTextArea);
jScrollPane2.setViewportView(clientTable);
postTextField.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
postTextFieldActionPerformed(evt);
}
});
kirimButton.setText("Kirim");
kirimButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
kirimButtonActionPerformed(evt);
}
});
jLabel2.setText("Server");
serverTextField.setText("127.0.0.1");
jLabel3.setText("Port");
portTextField.setText("9999");
masukButton.setText("Masuk");
masukButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
masukButtonActionPerformed(evt);
}
});
jLabel4.setText("Username");
usernameTextField.setText("animous");
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addContainerGap()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addComponent(postTextField)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(kirimButton))
.addComponent(jScrollPane1))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(jScrollPane2, javax.swing.GroupLayout.PREFERRED_SIZE, 259, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGroup(layout.createSequentialGroup()
.addComponent(jLabel2)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(serverTextField, javax.swing.GroupLayout.PREFERRED_SIZE, 167, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addComponent(jLabel3)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(portTextField, javax.swing.GroupLayout.PREFERRED_SIZE, 46, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addComponent(jLabel4)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(usernameTextField, javax.swing.GroupLayout.DEFAULT_SIZE, 194, Short.MAX_VALUE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(masukButton)))
.addContainerGap())
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addContainerGap()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel2)
.addComponent(serverTextField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(jLabel3)
.addComponent(portTextField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(masukButton)
.addComponent(jLabel4)
.addComponent(usernameTextField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jScrollPane2, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, 427, Short.MAX_VALUE)
.addGroup(layout.createSequentialGroup()
.addComponent(jScrollPane1)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(postTextField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(kirimButton))))
.addContainerGap())
);
pack();
}// </editor-fold>
private void masukButtonActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
this.server = serverTextField.getText();
this.port = new Integer(portTextField.getText());
this.username = usernameTextField.getText();
start();
}
private void kirimButtonActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
try {
String message = "postText~" + username + "~" + postTextField.getText() + "~all~\n";
output.writeObject(message);
postTextField.setText("");
} catch (IOException ex) {
Logger.getLogger(ChatClient.class.getName()).log(Level.SEVERE, null, ex);
}
}
private void postTextFieldActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
kirimButtonActionPerformed(evt);
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(ChatClient.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(ChatClient.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(ChatClient.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(ChatClient.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
new ChatClient().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JTable clientTable;
private javax.swing.JLabel jLabel2;
private javax.swing.JLabel jLabel3;
private javax.swing.JLabel jLabel4;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JScrollPane jScrollPane2;
private javax.swing.JButton kirimButton;
private javax.swing.JButton masukButton;
private javax.swing.JTextField portTextField;
private javax.swing.JTextField postTextField;
private javax.swing.JTextField serverTextField;
private javax.swing.JTextField usernameTextField;
private javax.swing.JTextArea viewTextArea;
// End of variables declaration
class ListenFromServer extends Thread {
@Override
public void run() {
while (true) {
try {
String msg = (String) input.readObject();
String res;
String type = msg.split("~")[0];
String pengirim = msg.split("~")[1];
String text = msg.split("~")[2];
String kepada = msg.split("~")[3];
switch (type) {
case "recieveText":
res = pengirim + ": " + text;
viewTextArea.setText(viewTextArea.getText() + res + "\n");
break;
case "recievePrivateText":
res = pengirim + ": " + text;
if (kepada.equals(username)) {
viewTextArea.setText(viewTextArea.getText() + res + "\n");
}
break;
case "login":
viewTextArea.setText(viewTextArea.getText() + pengirim + " sedah login..." + "\n");
clients.add(pengirim);
break;
case "logout":
viewTextArea.setText(viewTextArea.getText() + pengirim + " telah logout..." + "\n");
clients.remove(pengirim);
break;
case "list":
setTable(text);
break;
}
} catch (IOException e) {
System.out.println("Server has close the connection: " + e);
break;
} catch (ClassNotFoundException e2) {
}
}
}
private void setTable(String text) {
int rows = text.split(":").length - 1;
Object[][] data = new Object[rows][1];
for (int i = 0; i < rows; i++) {
String t = text.split(":")[i];
data[i][0] = t;
}
String[] header = {"Clients"};
clientTable.setModel(new DefaultTableModel(data, header));
}
}
}
Aplikasi ini dapat dikembangkan menjadi aplikasi chat yang lebih komplit seperti voice call, video call dengan menggunakan JMF (Java Media Framework)
Untuk pengembangannya menggunakan JMF dilanjutkan nanti pada tulisan selanjutnya…
Semoga bermanfaat…
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