Code this Java program: display the moving car using Applet

Member • Nov 30, 2008

The java file code is as follows:
It shows 4 cars crossing a square.

import java.awt.*;
import java.util.*;
import java.applet.*;
/*
 <APPLET CODE="Animation.JAVA" WIDTH=400 HEIGHT=300>
 </APPLET>
*/
//The basic applet class.The applet shows 4 cars crossing each other at a square.
public class Animation extends Applet implements Runnable
{
 Thread t;
 //4 variables used to vary the car's positions.
 int x1=0,x2=380,y1=50,y2=250;
 public void start()
 {
  if(t==null)
  {
   t=new Thread(this,"New Thread");//New side Thread created on start of applet.
   t.start();
  }
 }
 public void stop()
 {
  if(t!=null)
  {
   t=null;//On stop of applet the created thread is destroyed.
  }
 }
 //Implementation of method run() of Runnable interface.
 public void run()
 {
  Thread t1=Thread.currentThread();
  while(t==t1)
  {
   repaint();
   try
   {
    Thread.sleep(100);
   }
   catch(Exception e)
   {   }
  }
 }
 public void paint(Graphics g)
 {
  setBackground(Color.cyan);
  g.setColor(Color.BLACK);
  x1=(x1+16)%400;
  x2=x2-16;
  y1=(y1+12)%300;
  y2=y2-12;
  if(y2<0)
   y2=288;
  if(x2<0)
   x2=384;
  //Draw the roads using 2 filled rectangles using black color.
  g.fillRect(0,130,400,40);
  g.fillRect(180,0,40,305);
  //Draw the white colored lines.
  g.setColor(Color.white);
  for(int i=0;i<20;i++)
  {
   if(i!=9 && i!=10)
    g.drawLine(i*20,150,i*20+10,150);
  }
  for(int j=0;j<15;j++)
  {
   if(j!=7 && j!=8)
    g.drawLine(200,j*20,200,j*20+10);
  }
  //Draw 4 colored cars using filled round rectangles.
  g.setColor(Color.red);
  g.fillRoundRect(x2,152,20,8,2,2);
  g.fillRoundRect(x1,140,20,8,2,2);
  g.fillRoundRect(190,y1,8,20,2,2);
  g.fillRoundRect(202,y2,8,20,2,2);
 }
}

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lano51

Member • Jan 8, 2009

i take this code and try to run it on java but it doesnot run since it doesnot contain the main method that runs the program please can you send me the runnable code.thanks

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Ashutosh_shukla

Member • Jan 8, 2009

Hey it is an applet you don't have to run it as Java application
Instead you have to view it using the appletviewer

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rosario.n

Member • Jan 9, 2009

😕 i also tried that program.there is error in the class declaration.

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Ashutosh_shukla

Member • Jan 9, 2009

Hey you save it as Animation.java and try again if it does not work out still send me actual error i will see because it runs perfectly on my pc

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lano51

Member • Jan 9, 2009

hi i try again to run this applet but their is an error 😔 please send me step by step what should i do inorder to run this applet please reply as soon as possible as you can.thanks

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Ashutosh_shukla

Member • Jan 10, 2009

Hey listen you copy the code and store it in a file Animation.java
Next thing is to compile it with the jdk and then kepp the .class file in folder of bin. Now on comand prompt type
appletviewer Animation

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lano51

Member • Jan 12, 2009

hi again i face another problem i try to apply what you wrote but i donot know what is meant by jdk and the .class i donot have it, more over where is the location of the bin in the computer .
i create a file and name it animation.java but the rest of the steps i donot know how to apply it .so please send me the code in a zip file on my mail :
#-Link-Snipped-#
thank you very much for helping me 😁

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Ashutosh_shukla

Member • Jan 12, 2009

Hey listen you don't know jdk i mean it is same as the java installed on your machine.It has a bin folder and on compilation of a .java file you get a .class file created.Now simply you have to put this file in your bin and then compile it then you will get a Animation.class file.Then simply you have to use appletviwer command to view the applet.The bin folder contains an application file appletviewer.You need to go to command prompt and then write this command appletviewer Animation
Thats it it will run I guess you have never used java and compiled programs on command line interpreter. Try it once again i have already given you the code you just need to execute this steps properly

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rosario.n

Member • Jan 23, 2009

hey..i tried again.there is no error..but,i didn't get the car image..😕

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shalini_goel14

Member • Feb 1, 2009

rosario.n
hey..i tried again.there is no error..but,i didn't get the car image..😕

Hey rosario,

This code is working absolutely fine for me. Well done Mr. Ashutosh 😀

@rosario: Did you get the applet window? If not even that, follow the steps told by Mr. Ashutosh to run the program.😀

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rama_krish627

Member • Feb 6, 2009

Ya it's working ya. I got a moving cars in red color.

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zia.sepsis

Member • Aug 1, 2009

lano51
hi again i face another problem i try to apply what you wrote but i donot know what is meant by jdk and the .class i donot have it, more over where is the location of the bin in the computer .
i create a file and name it animation.java but the rest of the steps i donot know how to apply it .so please send me the code in a zip file on my mail :
#-Link-Snipped-#
thank you very much for helping me 😁

Jdk stands for java developing kit... which is an open source software developed by sun microsystem. only with the help of jdk the java source code is compiled into java byte code with the extension of (.class). the command instructing JDK to compile is "javac".
do the following:
1.Copy the above source code and paste it in a notepad.
2.save it with the "class name" i.e."Animation" with an extension (.java) (note: java is case sensitve)
3.For instance your saving this in a folder named "david" in your "c:", now open your "cmd" and type as following.
c:\documents and settings\user name> cd\
c:\> cd david
c:\david>
" you have located the desired directory now"
c:\david> javac Animation.java
c:\david>
(this denotes successfull execution of the program)
(please be sure that you have already installed jdk)
4. now "javac" instructs JDK to compile the given source code in java byte code with an extension of (.class). this compiled code will be saved in the same folder.
5. applets cannot be run'd as application because it doesn't hold's any main method. so it has to done by using appletviewer.
6. In order to run an applet you have to write an HTML document and include the applet into that.

<html>
<head>
<title> Display name applet </title>
</head>
<body>
<h1 align=center> Name web applet</h1>
<center>
<applet name="Animation" code="Animation.class" width=200 height=100></applet>
</center>
</body>
</html>

7. save it with an extension (.html)....in the folder david.
8. now--->
c:/david>appletviewer Animation.html

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zia.sepsis

Member • Aug 1, 2009

Its working.....😎

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spp

Member • Aug 1, 2009

i tried this code but its not working.
it showing an error that applet not initialized.
so can u please check this out

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zia.sepsis

Member • Aug 1, 2009

spp
i tried this code but its not working.
it showing an error that applet not initialized.
so can u please check this out

Have you installed JDK?????

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spp

Member • Aug 1, 2009

zia.sepsis
Have you installed JDK?????

yah i have installed jdk1.6

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zia.sepsis

Member • Aug 1, 2009

spp
yah i have installed jdk1.6

Try this:
c:\foldername>set path="directory of the jdk's bin";
eg:
"set path=c:\program files\java\jdk.1.5.0-06\bin;"

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spp

Member • Aug 1, 2009

yah i have already set that path
other applet applications are working but this one not

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Srikz

Member • Aug 20, 2009

Actually, inside the program the <applet> code must contain the class file and not the java file.
Once you change it, it'll work.
i.e <APPLET CODE="Animation.class" WIDTH=400 HEIGHT=300> </APPLET>

It Worked for me !!

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sookie

Member • Aug 21, 2009

Hi Srikz,

That program works if I use neither .java nor .class

Step # 1: Create a folder named "I:\JavaSrcCode" in your local
Step # 2: Open notepad, copy the program in this thread in it and save it as Animation.java in I:\JavaSrcCode folder. Also edit Animation.JAVA to simply Animation in Animation.java file.So final file would look like this

import java.awt.*;
import java.util.*;
import java.applet.*;
/*
 <APPLET CODE="Animation" WIDTH=400 HEIGHT=300>
 </APPLET>
*/
//The basic applet class.The applet shows 4 cars crossing each other at a square.
public class Animation extends Applet implements Runnable
{
 Thread t;
 //4 variables used to vary the car's positions.
 int x1=0,x2=380,y1=50,y2=250;
 public void start()
 {
  if(t==null)
  {
   t=new Thread(this,"New Thread");//New side Thread created on start of applet.
   t.start();
  }
 }
 public void stop()
 {
  if(t!=null)
  {
   t=null;//On stop of applet the created thread is destroyed.
  }
 }
 //Implementation of method run() of Runnable interface.
 public void run()
 {
  Thread t1=Thread.currentThread();
  while(t==t1)
  {
   repaint();
   try
   {
    Thread.sleep(100);
   }
   catch(Exception e)
   {   }
  }
 }
 public void paint(Graphics g)
 {
  setBackground(Color.cyan);
  g.setColor(Color.BLACK);
  x1=(x1+16)%400;
  x2=x2-16;
  y1=(y1+12)%300;
  y2=y2-12;
  if(y2<0)
   y2=288;
  if(x2<0)
   x2=384;
  //Draw the roads using 2 filled rectangles using black color.
  g.fillRect(0,130,400,40);
  g.fillRect(180,0,40,305);
  //Draw the white colored lines.
  g.setColor(Color.white);
  for(int i=0;i<20;i++)
  {
   if(i!=9 && i!=10)
    g.drawLine(i*20,150,i*20+10,150);
  }
  for(int j=0;j<15;j++)
  {
   if(j!=7 && j!=8)
    g.drawLine(200,j*20,200,j*20+10);
  }
  //Draw 4 colored cars using filled round rectangles.
  g.setColor(Color.red);
  g.fillRoundRect(x2,152,20,8,2,2);
  g.fillRoundRect(x1,140,20,8,2,2);
  g.fillRoundRect(190,y1,8,20,2,2);
  g.fillRoundRect(202,y2,8,20,2,2);
 }
}

Step #3: Now open command prompt. Switch to your I:\JavaSrcCode directory and enter following command. It will create Animation.class file in the same folder "I:\JavaSrcCode" folder.

javac I:\JavaSrcCode\Animation.java

Step 4: Now enter following command

appletviewer Animation.java

You will get applet window finally.

[IMG]

It has nothing to do with .java and .class until or unless you are keeping your .java and .class files at the same location. Better keep them at same place to avoid any compilications. For large projects only we should keep .class files separately.

Thanks !

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Srikz

Member • Aug 22, 2009

Hey sookie,
it's just that i happened to compile few other java programs using the .java extenstion in the applet code, which just failed. But it'd work along fine with the class extension. Anyhow, i'll try your method and let you know. Thanks 😀

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HImanshu_Sharma

Member • Mar 23, 2010

i haven't tried bt i'l actually i had an another programe of this moving car,,,i made myself..so think i can sort out your prob...

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Kavithak

Member • Aug 12, 2014

Ya ..it works...Thanks a lot..

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v.gowtham

Member • Oct 9, 2014

in my pc,at the applet page,on the bottom (start:applet not initialised)is displaying whats wrong...........?pls help me......!

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Bharath0bk

Member • Aug 14, 2015

I/O exception while reading: D:\Mycode\Animation (The system cannot find the fil e specified)

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Bharath0bk

Member • Aug 14, 2015

I/O exception while reading: D:\Mycode\Animation (The system cannot find the fil e specified)

i am getting this error?

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Aaditya Karankot

Member • Feb 12, 2016

D:\>AppletViewer a.html
load: class Animation.JAVA not found.
java.lang.ClassNotFoundException: Animation.JAVA
at sun.applet.AppletClassLoader.findClass(AppletClassLoader.java:211)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.applet.AppletClassLoader.loadClass(AppletClassLoader.java:144)
at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
at sun.applet.AppletClassLoader.loadCode(AppletClassLoader.java:662)
at sun.applet.AppletPanel.createApplet(AppletPanel.java:785)
at sun.applet.AppletPanel.runLoader(AppletPanel.java:714)
at sun.applet.AppletPanel.run(AppletPanel.java:368)
at java.lang.Thread.run(Thread.java:662)

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Aashish Chugh

Member • May 30, 2016

Yeah nice Coding ..

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