Building Simple GUI in Java – ChatClient

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Date;
 
/**
* Created by ismailsirma on 25.6.2015.
*/
public class ClientSwing {
 
    JTextField username;
    JTextField message;
    JLabel label1;
    JScrollPane jScrollPane1;
    JLabel statusbar;
    JButton button1;
    JButton button2;
    JTextArea textArea;
    JFrame frame;
    String usernamee = null;
    Date date = new Date();
 
    final static Color  ERROR_COLOR = Color.RED;
 
    ClientSwing(){
        // Create a frame
        frame = new JFrame("Chat Client");
        frame.setSize(500, 400);
 
        // create a text field for user to enter their name
        username = new JTextField();
        // create a text field for user to enter their message
        message = new JTextField();
        // text area where incoming and outgoing messages being seen
        textArea = new JTextArea();
        button1 = new JButton("Set nickname");
        button2 = new JButton("Send");
        label1 = new JLabel();
        statusbar = new JLabel();
 
        // How frame is closed
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setTitle("Chat Client");
 
        textArea.setColumns(20);
        textArea.setRows(5);
        textArea.setLineWrap(true);
        textArea.setWrapStyleWord(true);
        textArea.setEditable(false);
        jScrollPane1 = new JScrollPane(textArea);
 
        label1.setText("Enter your username:");
 
        // creates the graphical user interface
        SetLayout(frame, label1, username, message, statusbar, button1, button2, jScrollPane1);
 
 
        // set the frame visible
        frame.setVisible(true);
 
        // when user hits enter key in username field, show it on status bar
        username.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                usernamee = username.getText();
                statusbar.setText("Username set!");
                username.setEnabled(false);
                frame.setVisible(true);
            }
        });
 
        // when an action is performed, capture the action
        // button1 is the button sets the username
        button1.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                usernamee = username.getText();
                statusbar.setText("Username set!");
                username.setEnabled(false);
                frame.setVisible(true);
            }
        });
 
        message.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                if (usernamee == null) {
                    message.setText("");
                    // work in progress
                }
                textArea.append(usernamee + ": " + message.getText() + "\\n");
                //clear the message area
                message.setText("");
                //clear the status area
                statusbar.setText("");
                username.setEnabled(false);
                frame.setVisible(true);
            }
        });
 
        // button2 is the button sends the message
        button2.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                // take the text and put it on the label
 
                // if user didn't specify the user name
                if(usernamee == null){
                    message.setText("");
                    // work in progress
                }
                textArea.append(usernamee + ": " + message.getText() + "\\n");
                //clear the message area
                message.setText("");
                //clear the status area
                date = new Date();
                statusbar.setText("Your message at " + date.getHours() + ":" + date.getMinutes() + ":" + date.getSeconds() + " has been sent");
                username.setEnabled(false);
                frame.setVisible(true);
            }
        });
 
 
    }
 
    public static void main(String[] args) {
 
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                new ClientSwing();
            }
        });
 
    }
 
    public void SetLayout(JFrame frame,JLabel label, JTextField username, JTextField message, JLabel statusbar, JButton setusername, JButton send, JScrollPane jScrollPane){
 
        // Creating layout
        GroupLayout layout = new GroupLayout(frame.getContentPane());
        frame.getContentPane().setLayout(layout);
 
        //Create a parallel group for the horizontal axis
        GroupLayout.ParallelGroup hGroup = layout.createParallelGroup(GroupLayout.Alignment.LEADING);
 
        //Create a sequential and a parallel groups
        GroupLayout.SequentialGroup h1 = layout.createSequentialGroup();
        GroupLayout.ParallelGroup h2 = layout.createParallelGroup(GroupLayout.Alignment.TRAILING);
 
        //Add a container gap to the sequential group h1
        h1.addContainerGap();
 
        //Add a scroll pane and a label to the parallel group h2
        h2.addComponent(jScrollPane, GroupLayout.Alignment.LEADING, GroupLayout.DEFAULT_SIZE, 450, Short.MAX_VALUE);
        h2.addComponent(statusbar, GroupLayout.Alignment.LEADING, GroupLayout.DEFAULT_SIZE, 450, Short.MAX_VALUE);
 
        //Create a sequential group h3
        GroupLayout.SequentialGroup h3 = layout.createSequentialGroup();
        h3.addComponent(label, 0, GroupLayout.DEFAULT_SIZE, 150);
        h3.addComponent(username, 0, GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE);
        h3.addComponent(setusername, 0, GroupLayout.DEFAULT_SIZE, 120);
 
        // new added
        GroupLayout.SequentialGroup h4 = layout.createSequentialGroup();
        h4.addComponent(message, 0, GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE);
        h4.addComponent(send, 0, GroupLayout.DEFAULT_SIZE, 120);
 
        hGroup.addGroup(h4);
        //Add the group h3 to the group h2
        hGroup.addGroup(h3);
        //Add the group h2 to the group h1
        hGroup.addGroup(h2);
 
        h1.addContainerGap();
 
 
        //Add the group h1 to the hGroup
        hGroup.addGroup(GroupLayout.Alignment.TRAILING, h1);
        //Create the horizontal group
        layout.setHorizontalGroup(hGroup);
 
 
        //Create a parallel group for the vertical axis
        GroupLayout.ParallelGroup vGroup = layout.createParallelGroup();
        //Create a sequential group v1
        GroupLayout.SequentialGroup v1 = layout.createSequentialGroup();
        //Add a container gap to the sequential group v1
        v1.addContainerGap();
        //Create a parallel group v3
        GroupLayout.ParallelGroup v3 = layout.createParallelGroup(GroupLayout.Alignment.BASELINE);
        v3.addComponent(label);
        v3.addComponent(username);
        v3.addComponent(setusername);
        //Create a parallel group v2
        GroupLayout.ParallelGroup v2 = layout.createParallelGroup(GroupLayout.Alignment.BASELINE);
        v2.addComponent(message,0,70,300);
        v2.addComponent(send);
        //Add the group v2 tp the group v1
        v1.addGroup(v3);
        v1.addGroup(v2);
        v1.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED);
        v1.addComponent(jScrollPane, 0, GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE);
        v1.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED);
        v1.addComponent(statusbar);
        v1.addContainerGap();
 
        //Add the group v1 to the group vGroup
        vGroup.addGroup(v1);
        //Create the vertical group
        layout.setVerticalGroup(vGroup);
 
        //Window to be sized to fit the preferred size and layouts of its sub components.
        //The resulting width and height of the window are automatically enlarged if either of dimensions
        //is less than the minimum size as specified by the previous call to the setMinimumSize method.
        frame.pack();
    }
}