using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ErrorDemo
{
    class ErrorDemo
    {
        public static void Main(String[] args)
        {
            int a, b, ans;
            int[] no = new int[5];
            try
            {
                a = int.Parse(args[0]);
                b = 10;
                ans = b / a;
                Console.WriteLine("ans=" + ans);
                no[4] = ans;
                Console.WriteLine(no[3]);
            }
            catch (DivideByZeroException e)
            {
                Console.WriteLine("Division by 0");
            }
            catch (Exception e)
            {
                Console.WriteLine(e);
            }
            Console.WriteLine("After try catch block");
            Console.ReadKey();      
        }
    }
}

TreeD.java

import javax.swing.*;
import javax.swing.tree.*;
import javax.swing.event.*;
import java.applet.*;
import java.awt.*;
/*<applet code="TreeD" width=600 height=400>
</applet> */
public class TreeD extends JApplet implements TreeSelectionListener
{
JTree tr;
JLabel l1;
DefaultMutableTreeNode top,a,a1,a2,b,b1,b2,b3;
public void init()
{
top=new DefaultMutableTreeNode("Options");
a=new DefaultMutableTreeNode("A");
top.add(a);
a1=new DefaultMutableTreeNode("A1");
a.add(a1);
a2=new DefaultMutableTreeNode("A2");
a.add(a2);
b=new DefaultMutableTreeNode("B");
top.add(b);
b1=new DefaultMutableTreeNode("B1");
b.add(b1);
b2=new DefaultMutableTreeNode("B2");
b.add(b2);
b3=new DefaultMutableTreeNode("B3");
b.add(b3);
tr=new JTree(top);
JScrollPane s=new JScrollPane(tr);
add(s);
l1=new JLabel();
add(l1,BorderLayout.SOUTH);
tr.addTreeSelectionListener(this);
}
public void valueChanged(TreeSelectionEvent tse)
{
l1.setText("Selected path is" +tse.getPath());
}
}

//Use appletviewer TreeD.java to execute the program

JAVA download link!!

The following link can be used to download java development kit for your PC!!
http://www.oracle.com/technetwork/java/javase/downloads/jdk-6u25-download-346242.html

To download eclipse for java the link is:
http://www.eclipse.org/downloads/

!!Enjoy programming!!

Animal.java

//U need to copy these images to a folder where you are going to save this program!!
import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

import javax.swing.event.*;

import java.applet.*;

/*<applet code="Animal" width=1000 height=700>

</applet>*/

public class Animal extends JApplet implements ActionListener,ListSelectionListener

{

JList li1;

JLabel l1;

JScrollPane s1;

JButton b1;

String [] Animals={"Dog","Elephant","Lion","Rat","Tiger"};

ImageIcon i1=new ImageIcon("Dog.png");

ImageIcon i2=new ImageIcon("Elephant.png");

ImageIcon i3=new ImageIcon("Lion.png");

ImageIcon i4=new ImageIcon("Rat.png");

ImageIcon i5=new ImageIcon("Tiger.png");

public void init()

{

Container cp=getContentPane();

cp.setLayout(new FlowLayout());

li1=new JList(Animals);

li1.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);

s1=new JScrollPane(li1);

l1=new JLabel();

b1=new JButton("Clear");

cp.add(s1);

cp.add(l1);

cp.add(b1);

li1.addListSelectionListener(this);

b1.addActionListener(this);

}

public void valueChanged(ListSelectionEvent le)

{

int i;

i=li1.getSelectedIndex();

if(i==0)

{

l1.setIcon(i1);

}

else if(i==1)

{

l1.setIcon(i2);

}

else if(i==2)

{

l1.setIcon(i3);

}

else if(i==3)

{

l1.setIcon(i4);

}

else if(i==4)

{

l1.setIcon(i5);

}

}

public void actionPerformed(ActionEvent ae)

{

l1.setVisible(false);

li1.clearSelection();

}

}