Marauroa Chat Tutorial: Difference between revisions

// Something weird happened while applying perception

=== Output ===

Ideally you should see something like

<pre>

>java -cp marauroa.jar;log4j.jar;. Test test1 test1

Cannot find log4j.properties in classpath. Using default properties.

0.5

Do not contact us!

Marauroa server

Chat

*test1* : test50

*test1* : test150

</pre>

Note the message about log4j.properties: you can create that file in order to configure the Log4J usage inside Marauroa framework.

=== Code ===

The design of our Client class allows us to easily use it in something more complex then Test class above. Here is the example of a simple Swing application that uses Client as a communication tool

<pre>

import javax.swing.*;

import java.awt.event.*;

import java.io.IOException;

import java.net.URL;

import java.util.*;

import java.awt.*;

public class View extends JFrame implements ActionListener {

private javax.swing.JButton jSayButton;

private javax.swing.JButton jConnectButton;

private javax.swing.JScrollPane jScrollPane1;

private javax.swing.JTextArea jChatArea;

private javax.swing.JTextField jInputField;

private javax.swing.Timer timer;

private Client client = null;

public View() {

initComponents();

jSayButton.addActionListener(

new ActionListener() {

public void actionPerformed(ActionEvent e) {

String message = jInputField.getText();

jInputField.setText("");

client.SendMessage(message);

}

});

jConnectButton.addActionListener(

new ActionListener() {

public void actionPerformed(ActionEvent e) {

try {

client = Client.get();

client.connect("127.0.0.1", 555);

client.login("test1", "test1");

client.chooseCharacter("test1");

jSayButton.setEnabled(true);

jInputField.setEnabled(true);

} catch (Exception exception) {

JOptionPane.showMessageDialog(

View.this, "Error", exception.toString(), JOptionPane.WARNING_MESSAGE);

client = null;

}

}

});

timer = new javax.swing.Timer(300, this);

timer.setInitialDelay(500);

timer.start();

setVisible(true);

}

public void actionPerformed(ActionEvent e) {

if (client != null) {

client.loop(0);

String s = client.popQuote();

while (s != null) {

jChatArea.append(s + "\n");

s = client.popQuote();

}

}

}

private void initComponents() {

jScrollPane1 = new javax.swing.JScrollPane();

jChatArea = new javax.swing.JTextArea();

jSayButton = new javax.swing.JButton();

jConnectButton = new javax.swing.JButton();

jInputField = new javax.swing.JTextField();

setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

setTitle("Chat 0.5");

setName("main");

jChatArea.setColumns(20);

jChatArea.setEditable(false);

jChatArea.setRows(5);

jScrollPane1.setViewportView(jChatArea);

jSayButton.setText("Say");

jSayButton.setEnabled(false);

jConnectButton.setText("Connect");

jInputField.setEnabled(false);

javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());

getContentPane().setLayout(layout);

layout.setHorizontalGroup(

layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)

.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()

.addContainerGap()

.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)

.addComponent(jScrollPane1, javax.swing.GroupLayout.Alignment.LEADING, javax.swing.GroupLayout.DEFAULT_SIZE, 394, Short.MAX_VALUE)

.addGroup(layout.createSequentialGroup()

.addComponent(jInputField, javax.swing.GroupLayout.PREFERRED_SIZE, 236, javax.swing.GroupLayout.PREFERRED_SIZE)

.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)

.addComponent(jSayButton, javax.swing.GroupLayout.DEFAULT_SIZE, 73, Short.MAX_VALUE)

.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)

.addComponent(jConnectButton)))

.addContainerGap())

);

layout.setVerticalGroup(

layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)

.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()

.addContainerGap()

.addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 249, Short.MAX_VALUE)

.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)

.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)

.addComponent(jConnectButton)

.addComponent(jSayButton)

.addComponent(jInputField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))

.addContainerGap())

);

pack();

}

}

</pre>

To create the layout of the elements NetBeans was used, but we concentrate just on the source code here.

The client establishes a connection to a hard-coded location upon Connect button is pressed. There is no "Create new account" functionality, so account should be created beforehand.

We use timer to regularly check for the new messages in the Client queue. If there are some - they are put to the large text box. Sending the new message also relies on the Client facilities.

The only thing left for the Swing client now is a main method. Here is the source code

<pre>

final class Chat {

private Chat() {}

public static void main( String[] args ) {

new View();

}

}

</pre>

=== Deployment ===

You still use the same command for compilation

<pre>

javac -cp marauroa.jar;log4j.jar;. *.java

</pre>

Make sure that source files with code for Swing client are in the same directory with jars mentioned and Client.java file. You can run the client with the following command

<pre>

java -cp marauroa.jar;log4j.jar;. Chat

</pre>