Doubt on line removal in JTextArea

Question

Hi All,
I have 3 lines which are on the JTextArea like
sample.pl
sample1.pl
sample2.pl
So i want to remove the whole from Jtextarea..how is it possible??
thanks in advance.
regards,
Viswanadh

Answer 1

TechnicalGuy7 wrote:
Thanks for the reply.
If suppose i want to remove only the middle line..How can i do???
regards,
Viswanadh
Edited by: TechnicalGuy7 on Feb 16, 2009 5:21 AMI've written a simple example which will remove the second line of the input when you press a button. Obviously you can manipulate the logic to remove whatever line you want (programmatically determining where the middle lines is, removing odd lines etc).
package tester;
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JTextArea;
public class Tester extends JFrame implements WindowListener {
     private JTextArea textArea;
     public static void main(String[] args) {
          new Tester();
     public Tester() {
          textArea = new JTextArea();
          JButton checkTextButton = new JButton("Click to remove the second line");
          checkTextButton.addActionListener(new ActionListener() {
               public void actionPerformed(ActionEvent e) {
                    checkTextButton_actionPerformed(e);
          this.setLayout(new BorderLayout());
          this.add(textArea, BorderLayout.CENTER);
          this.add(checkTextButton, BorderLayout.SOUTH);
          this.setTitle("Second Line Remover");
          this.setSize(500, 500);
          this.addWindowListener(this);
          this.setVisible(true);
     private void checkTextButton_actionPerformed(ActionEvent e) {
          // Get the text from the text area
          String inputText = textArea.getText();
           * Split the text into lines using the new line character as the split point. lines[0] is
           * the first line, lines[1] is the second and so on...
          String[] lines = inputText.split("\n");
          // If there aren't 2 or more lines we can't do anything
          if(lines.length < 2) {
               JOptionPane.showMessageDialog(this, "Cannot remove the second line because it doesn't exist.");
               return;
          StringBuilder outputString = new StringBuilder();
          for(int i=0; i<lines.length; i++) {
               // Append all lines except from the second line to the new text to put in the area
               if(i != 1) {
                    outputString.append(lines[i]+"\n");
          // Set the new text in the area to be the input minus the second line
          textArea.setText(outputString.toString());
     @Override
     public void windowActivated(WindowEvent e) {}
     public void windowClosed(WindowEvent e) {}
     public void windowClosing(WindowEvent e) {
          System.exit(0);
     public void windowDeactivated(WindowEvent e) {}
     public void windowDeiconified(WindowEvent e) {}
     public void windowIconified(WindowEvent e) {}
     public void windowOpened(WindowEvent e) {}
}Sample interaction (before and after pressing the button:
http://img4.imageshack.us/img4/4307/beforeandafterva5.jpg