In java code, how to obtain the input a user types in JTextArea

Question

In my java code, I have two JTextArea. When a user
starts the GUI, there are two testareas showing up
(by typing: java xxx). The user types in words and
sentences in the first testarea, and how can I code
the java program so that something can come out
on the second testarea, with that something depends
on what the words are.

Answer 1

import javax.swing.*;
import javax.swing.event.*;
import java.awt.*;
import java.awt.event.*;
public class GUI extends JFrame{
    JTextArea jta1, jta2;
    public static void main(String args[]){
        GUI g = new GUI();
        g.addWindowListener(new WindowAdapter(){
            public void windowClosing(WindowEvent we){
                  System.exit(1);         
        g.setSize(400,300);
        g.setVisible(true);   
    public GUI(){
        JPanel p = new JPanel();
        p.setLayout(new FlowLayout());
        jta1 = new JTextArea(10,10);
        jta1.setLineWrap(true);
        jta1.addKeyListener(new KeyAdapter() {
            public void keyTyped(KeyEvent e) {
                char c = e.getKeyChar();
                jta2.append(String.valueOf(c));
        jta2 = new JTextArea(10,10);
        jta2.setLineWrap(true);
        p.add(jta1);
        p.add(jta2);
        getContentPane().add(p);
} You can implement whatever logic you want inside the keyTyped method.