Decimal to Hexadecimal convertor (10to16 convertor)using JAVA

 
class extra
{
 public static void main(String args[])
 {
  hexadecimal h=new hexadecimal();
  int a1,a2=0;
  char c;
  a1=Integer.parseInt(args[0]);
  //System.out.println(h.hax(a1,a2));
  h.hax(a1);
 }
}


class hexadecimal
{
 void hax(int a1)
 {
  int b;
  char c;
  b=a1%16;
  a1=a1/16;
  if(a1>16)
  {
   hax(a1); 
  }
  System.out.print(a1);
  if(b==0 && a1<16)
  {
   System.out.print(0);
  }
  if(b>9)
  {
   c=(char)(b+55);
   System.out.print(c);
  }
  else
  {
   System.out.print(b);
  }
  return;
 }
}

Sticky Oval in JAVA

import java.awt.*;
import java.awt.event.*;
import java.applet.*;

public class sticky_oval extends Applet implements MouseMotionListener {
 int x,y;
 public void init() {
  addMouseMotionListener(this);
 }
 public void mouseMoved(MouseEvent me) {
  x=me.getX();
  y=me.getY();
  repaint();
 }
 public void mouseDragged(MouseEvent me) {
 
 }
 public void paint(Graphics g) {
  try {
   g.drawOval(x,y,x,y);
   if(x==y) {
    g.setColor(Color.blue);
    g.fillOval(x,y,x,y);
    showStatus("THIS IS PERFECT CIRCLE.");
    Thread.sleep(4000);
   } else showStatus("");
  } catch(InterruptedException e) {
  
  }
 }
} 

Calculator using Buttons in JavaScript

<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Untitled Document</title>
<style type="text/css">
.box {
 width:15px;
 height:15px;
}
</style>
</head>

<body>
<script type="text/javascript">
 var no1="",no2="";
 var flag=0;
 var flag2=0;
 var already=0;
 function calc(id,txt)
 {
  
  if(flag==0)
  {
   no1=no1+document.getElementById(id).value;
   document.getElementById(txt).value=no1;
  }
  else if(flag==1)
  {
   no2=no2+document.getElementById(id).value;
   document.getElementById(txt).value=no2;
  }
 }
 function change(id)
 {
  if(already==0)
  {
  flag=1;
  already=1;
  var sign=document.getElementById(id).value;
  
  if(sign=='+')
  {
   if(flag2==0) document.getElementById('one').value=document.getElementById('two').value;
   document.getElementById('one').value=document.getElementById('one').value+"+";
   flag2=1;
  }
  if(sign=='-')
  {
   if(flag2==0) document.getElementById('one').value=document.getElementById('two').value;
   document.getElementById('one').value=document.getElementById('one').value+"-";
   flag2=1;
  }
  if(sign=='*')
  {
   if(flag2==0) document.getElementById('one').value=document.getElementById('two').value;
   document.getElementById('one').value=document.getElementById('one').value+"*";
   flag2=1;
  }
  if(sign=='/')
  {
   if(flag2==0) document.getElementById('one').value=document.getElementById('two').value;
   document.getElementById('one').value=document.getElementById('one').value+"/";
   flag2=1;
  }
  document.getElementById('two').value="";
  }
  
  
 }
 function ans(id)
 {
  var txt1=document.getElementById('one').value;
  var no1=txt1.substr(0,txt1.length-1);
  var no2= document.getElementById('two').value;
  flag=3;
  
  <!--var no2=document.getElementById('two').value;-->
  
  <!--var txt1=document.getElementById('one').value;-->
  <!--var no2=no1.substr(0,txt1.length-2);-->
  no1=parseInt(no1);
  no2=parseInt(no2);
  
  if(txt1.charAt(txt1.length-1)=='+') document.getElementById('ans').value=(no1+no2);
  if(txt1.charAt(txt1.length-1)=="-") document.getElementById('ans').value=(no1-no2);
  if(txt1.charAt(txt1.length-1)=="*") document.getElementById('ans').value=(no1*no2);
  if(txt1.charAt(txt1.length-1)=="/") 
  {
   try 
   {
    if(no2!=0) document.getElementById('ans').value=(no1/no2);
    else  document.getElementById('ans').value="Error while dividing";
   }
   catch(err)
   {
    document.getElementById('ans').value="by Zero is not possible";
   }
  }
  
 }
 function clear1()
 {
  document.getElementById('one').value="no1";
  document.getElementById('two').value="no2"
  document.getElementById('ans').value="answer";
  no1="";
  no2="";
  flag=0;
  flag2=0;
  already=0;
 }
 
</script>

<input type="text" id="one" readonly="readonly" value="no1"/><br />
<input type="text" id="two" readonly="readonly" value="no2"/><br />
<input type="text" id="ans" value="answer" readonly="readonly" />

<table width="30%" cellpadding="0" cellpadding="0">
<tr>
  <td><input type="button" id="01" value="1" onclick="return calc(this.id,'two')"/>
  <input type="button" id="2" value="2" onclick="return calc(this.id,'two')"/>
  <input type="button" id="3" value="3" onclick="return calc(this.id,'two')"/>
  <input type="button" id="add" value="+" onclick="return change(this.id)" />
 </td>
</tr>
<tr>
<td>
  <input type="button" id="4" value="4" onclick="return calc(this.id,'two')"/>
  <input type="button" id="5" value="5" onclick="return calc(this.id,'two')"/>
  <input type="button" id="6" value="6" onclick="return calc(this.id,'two')"/>
  <input type="button" id="sub" value="-" onclick="return change(this.id)" />
</td>
</tr>
<tr>
<td>
  <input type="button" id="7" value="7" onclick="return calc(this.id,'two')"/>
  <input type="button" id="8" value="8" onclick="return calc(this.id,'two')"/>
  <input type="button" id="9" value="9" onclick="return calc(this.id,'two')"/>
  <input type="button" id="mul" value="*" onclick="return change(this.id)" />
</td>
</tr>
<tr>
<td>
 <input type="button" id="c" value="C" onclick="return clear1()"/>
 <input type="button" id="0" value="0" onclick="return calc(this.id,'two')"/>
 <input type="button" id="equal" value="=" onclick="return ans(this.id)"/>
 <input type="button" id="div" value="/" onclick="return change(this.id)" />
</td>
</tr>
</table>


</body>
</html>