Not handling button event?

Question

//package com.ociweb.preferencestest;
import java.awt.event.*;
import java.util.prefs.*;
import javax.swing.*;
* A frame to test some basic functionality
* in the Preferences API
* @author Object Computing Inc.
public class PreferenceTestFrame extends JFrame implements ActionListener {
// A reference to a Preferences object
private Preferences myPreferences = null;
// Default values for this frame's preferences
public static final int DEFAULT_WINDOW_X = 50;
public static final int DEFAULT_WINDOW_Y = 50;
public static final int DEFAULT_WINDOW_WIDTH = 300;
public static final int DEFAULT_WINDOW_HEIGHT = 100;
// Keys for this frame's preferences
public static final String WINDOW_X_KEY = "TEST_WINDOW_X";
public static final String WINDOW_Y_KEY = "TEST_WINDOW_Y";
public static final String WINDOW_WIDTH_KEY = "TEST_WINDOW_WIDTH";
public static final String WINDOW_HEIGHT_KEY = "TEST_WINDOW_HEIGHT";
public PreferenceTestFrame() {
setTitle("Preferences Test Window");
// Obtain a references to a Preferences object
myPreferences = Preferences.userNodeForPackage(PreferenceTestFrame.class);
// Retrieve the location of the frame from the Preferences object
int windowX = myPreferences.getInt(WINDOW_X_KEY, DEFAULT_WINDOW_X);
int windowY = myPreferences.getInt(WINDOW_Y_KEY, DEFAULT_WINDOW_Y);
// Retrieve the size of the frame from the Preferences object
int windowWidth =
myPreferences.getInt(WINDOW_WIDTH_KEY, DEFAULT_WINDOW_WIDTH);
int windowHeight =
myPreferences.getInt(WINDOW_HEIGHT_KEY, DEFAULT_WINDOW_HEIGHT);
// Set the size and location of the frame
setBounds(windowX, windowY, windowWidth, windowHeight);
JButton but=new JButton("Click me");
add(but);
but.addActionListener(this);
setVisible(true);
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent we) {
exitApp();
public void actionPerformed(ActionEvent e) {
     if(e.getActionCommand == "Click me" )
     setbackground(Color.blue);
private void exitApp() {
// Save the state of the window as preferences
myPreferences.putInt(WINDOW_WIDTH_KEY, getWidth());
myPreferences.putInt(WINDOW_HEIGHT_KEY, getHeight());
myPreferences.putInt(WINDOW_X_KEY, getX());
myPreferences.putInt(WINDOW_Y_KEY, getY());
System.exit(0);
public static void main(String[] args) {
new PreferenceTestFrame();
On compliation I get the following error:
---------- javac ----------
PreferenceTestFrame.java:59: illegal start of expression
public void actionPerformed(ActionEvent e) {
^
PreferenceTestFrame.java:76: ';' expected
^
PreferenceTestFrame.java:76: '}' expected
^
3 errors
Output completed (0 sec consumed) - Normal Termination
Wheres the problem?

Answer 1

sorry, the missing braces (}) should be placed below:
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent we) {
exitApp();
} //missing
public void actionPerformed(ActionEvent e) {
     if(e.getActionCommand == "Click me" )
     setbackground(Color.blue);
}and some other changes that u need:
import java.awt.Color;
e.getActionCommand should be e.getActionCommand()
setbackground() should be setBackground()
hth.