This is a login form for a slot machine game which will evoke a "NextPage" object. I don't think this LoginDemo.java code has to do anything with the error but I prefer to post the entire code. Thanks in advance..
//LoginDemo.java
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
class Login extends JFrame implements ActionListener
{
JButton SUBMIT;
JPanel panel;
JLabel label1,label2;
final JTextField text1,text2;
Login()
{
label1 = new JLabel();
label1.setText("Username:");
label1.setBounds(50,50,100,30);
text1 = new JTextField(15);
text1.setBounds(250,50,100,30);
label2 = new JLabel();
label2.setText("Password:");
label2.setBounds(50,250,100,30);
text2 = new JPasswordField(15);
text2.setBounds(250,250,100,30);
//this.setLayout(new BorderLayout());
SUBMIT=new JButton("SUBMIT");
SUBMIT.setBounds(350,350,100,30);
// panel=new JPanel(new GridLayout(3,1));
panel=new JPanel(null);
panel.setBounds(50,50,1000,1000);
// panel.setLayout(new FlowLayout());
panel.add(label1);
panel.add(text1);
panel.add(label2);
panel.add(text2);
panel.add(SUBMIT);
add(panel,BorderLayout.CENTER);
SUBMIT.addActionListener(this);
setTitle("LOGIN FORM");
}
public void actionPerformed(ActionEvent ae)
{
String value1=text1.getText();
String value2=text2.getText();
if (value1.equals("a") && value2.equals("a"))
{
NextPage page=new NextPage();
page.setVisible(true);
//JLabel label = new JLabel("Welcome:"+value1);
// page.getContentPane().add(label);
setVisible(false);
}
else
{
//System.out.println("enter the valid username and password");
JOptionPane.showMessageDialog(this,"Incorrect login or password","Error",JOptionPane.ERROR_MESSAGE);
}
}
}
class LoginDemo
{
public static void main(String arg[])
{
try
{
Login frame=new Login();
frame.setSize(1000,1000);
frame.setVisible(true);
}
catch(Exception e)
{
JOptionPane.showMessageDialog(null, e.getMessage());
}
}
}
//NextPage.java
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.applet.*;
import java.util.Random;
import java.sql.*;
import java.lang.*;
import java.awt.image.*;
import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;
import java.io.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class NextPage extends JFrame implements Runnable, ActionListener
{
BufferedImage img1,i0,i1,i2,i3,i4,i5,i6,i7,i8,i9,i10,i11,i12,star1;
JFrame f1;
Thread t1,t2,t3;
int x1,y1,i,j,k,l,m,n,r1,r2,r3;
JButton b1;
Random r=new Random();
TextField tf1;
JPanel p1;
NextPage()
{
setBounds(50,50,1000,1000);
p1=(JPanel)(getContentPane());
p1.setBounds(50,50,1000, 1000);
p1.setLayout(null);
//tf1=new TextField(20);
//tf1.setBounds(50,50,100,30);
setDefaultCloseOperation(javax.swing.WindowConstants.DISPOSE_ON_CLOSE);
setTitle("Welcome");
b1=new JButton("START");
//p1.add(tf1);
b1.setBounds(150,400,100,30);
//try{
b1.addActionListener(this);
//}
/*catch(Exception e)
{
System.out.println(""+e);
}*/
add(b1);
setVisible(true);
try
{
i0=ImageIO.read(new File("tea.jpg"));
i1=ImageIO.read(new File("coffee.jpg"));
i2=ImageIO.read(new File("bhel.jpg"));
i3=ImageIO.read(new File("pizza.jpg"));
i4=ImageIO.read(new File("icecream.jpg"));
i5=ImageIO.read(new File("dosa.jpg"));
i6=ImageIO.read(new File("idli.jpg"));
i7=ImageIO.read(new File("panipuri.jpg"));
i8=ImageIO.read(new File("orange.jpg"));
i9=ImageIO.read(new File("watermelon.jpg"));
i10=ImageIO.read(new File("pavbhaji.jpg"));
i11=ImageIO.read(new File("noodles.jpg"));
i12=ImageIO.read(new File("sandwich.jpg"));
}
catch (IOException ie)
{
System.out.println("Error:"+ie.getMessage());
}
j=0; m=0; n=0;
r1= r.nextInt(13);
r2= r.nextInt(13);
r3= r.nextInt(13);
}
public void init()
{
t1=new Thread(this);
t2=new Thread(this);
t3=new Thread(this);
}
public void start()
{
t2.start();
t3.start();
}
public void run()
{
try
{
if(Thread.currentThread()==t1)
for(j=0; j<150; j++)
//for(i=0; i<=150; i+=20)
{
r1= r.nextInt(13);
repaint();
t1.sleep(10);
}
if(Thread.currentThread()==t2)
for(m=0; m<160; m++)
//for(k=0; k<=150; k+=20)
{
r2= r.nextInt(13);
repaint();
t2.sleep(10);
}
if(Thread.currentThread()==t3)
for(n=0; n<170; n++)
//for(l=0; l<=150; l+=20)
{
r3= r.nextInt(13);
repaint();
t3.sleep(10);
}
}
catch(Exception e)
{
System.out.println(""+e);
}
}
public void paint(Graphics g)
{
g.setColor(Color.blue);
g.drawRect(50,300,150,80);
g.drawRect(200,300,150,80);
g.drawRect(350,300,150,80);
switch(r1)
{
case 0: g.drawImage(i0,65,300,this);
break;
case 1: g.drawImage(i1,65,300,this);
break;
case 2: g.drawImage(i2,65,300,this);
break;
case 3: g.drawImage(i3,65,300,this);
break;
case 4: g.drawImage(i4,65,300,this);
break;
case 5: g.drawImage(i5,65,300,this);
break;
case 6: g.drawImage(i6,65,300,this);
break;
case 7: g.drawImage(i7,65,300,this);
break;
case 8: g.drawImage(i8,65,300,this);
break;
case 9: g.drawImage(i9,65,300,this);
break;
case 10: g.drawImage(i10,65,300,this);
break;
case 11: g.drawImage(i11,65,300,this);
break;
case 12: g.drawImage(i12,65,300,this);
break;
}
switch(r2)
{
case 0: g.drawImage(i0,215,300,this);
break;
case 1: g.drawImage(i1,215,300,this);
break;
case 2: g.drawImage(i2,215,300,this);
break;
case 3: g.drawImage(i3,215,300,this);
break;
case 4: g.drawImage(i4,215,300,this);
break;
case 5: g.drawImage(i5,215,300,this);
break;
case 6: g.drawImage(i6,215,300,this);
break;
case 7: g.drawImage(i7,215,300,this);
break;
case 8: g.drawImage(i8,215,300,this);
break;
case 9: g.drawImage(i9,215,300,this);
break;
case 10: g.drawImage(i10,215,300,this);
break;
case 11: g.drawImage(i11,215,300,this);
break;
case 12: g.drawImage(i12,215,300,this);
break;
}
switch(r3)
{
case 0: g.drawImage(i0,365,300,this);
break;
case 1: g.drawImage(i1,365,300,this);
break;
case 2: g.drawImage(i2,365,300,this);
break;
case 3: g.drawImage(i3,365,300,this);
break;
case 4: g.drawImage(i4,365,300,this);
break;
case 5: g.drawImage(i5,365,300,this);
break;
case 6: g.drawImage(i6,365,300,this);
break;
case 7: g.drawImage(i7,365,300,this);
break;
case 8: g.drawImage(i8,365,300,this);
break;
case 9: g.drawImage(i9,365,300,this);
break;
case 10: g.drawImage(i10,365,300,this);
break;
case 11: g.drawImage(i11,365,300,this);
break;
case 12: g.drawImage(i12,365,300,this);
break;
}
}
public void actionPerformed(ActionEvent ae)
{
if(ae.getSource()==b1)
t1.start();
}
/*public static void main(String args[])
{
NextPage o=new NextPage();
}*/
}
}
Here are the exceptions that I get-
F:\java\jdk\bin>java LoginDemo
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at NextPage.actionPerformed(NextPage.java:235)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318)
atjavax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
at java.awt.Component.processMouseEvent(Component.java:6289)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3267)
at java.awt.Component.processEvent(Component.java:6054)
at java.awt.Container.processEvent(Container.java:2041)
at java.awt.Component.dispatchEventImpl(Component.java:4652)
at java.awt.Container.dispatchEventImpl(Container.java:2099)
at java.awt.Component.dispatchEvent(Component.java:4482)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4577)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4238)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4168)
at java.awt.Container.dispatchEventImpl(Container.java:2085)
at java.awt.Window.dispatchEventImpl(Window.java:2478)
at java.awt.Component.dispatchEvent(Component.java:4482)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:644)
at java.awt.EventQueue.access$000(EventQueue.java:85)
at java.awt.EventQueue$1.run(EventQueue.java:603)
at java.awt.EventQueue$1.run(EventQueue.java:601)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87
at
java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:98
at java.awt.EventQueue$2.run(EventQueue.java:617)
at java.awt.EventQueue$2.run(EventQueue.java:615)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87
at java.awt.EventQueue.dispatchEvent(EventQueue.java:614)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
Can't get any solution.. I am a learner..please help..