Assignment-14

Implement student database in java using Applet.

Source Code:

import java.util.*;
import java.applet.*;
import java.awt.*;
import java.awt.event.*;//ActionListener Interface


public class studentapp extends Applet implements ActionListener
{
	LinkedList ll=new LinkedList();
	Label l1,l2,l3,l4,l5;
	TextField t1,t2,t3,t4,t5;
	Button b1,b2,b3,b4,b5;
	String s1,s2,s3,s4,s5;
	public void init()
	{
	l1=new Label("Name");
	add(l1);
	t1=new TextField(40);
	add(t1);
	l2=new Label("Class");
	add(l2);
	t2=new TextField(40);
	add(t2);
	l3=new Label("Roll No");
	add(l3);
	t3=new TextField(40);
	add(t3);
	l4=new Label("Marks");
	add(l4);
	t4=new TextField(40);
	add(t4);
	l5=new Label("D.O.B");
	add(l5);
	t5=new TextField(40);
	add(t5);
	b2=new Button("Add");
	add(b2);
	b3=new Button("Delete");
	add(b3);
	b4=new Button("Update");
	add(b4);
	b5=new Button("Search");
	add(b5);
	b1=new Button("CLEAR");
	add(b1);
	t1.addActionListener(this);
	t2.addActionListener(this);
	t3.addActionListener(this);
	t4.addActionListener(this);
	t5.addActionListener(this);
	b2.addActionListener(this);
	b3.addActionListener(this);
	b4.addActionListener(this);
	b5.addActionListener(this);
	b1.addActionListener(this);
	}

	public void actionPerformed(ActionEvent ae)
	{
	
	 if(ae.getSource()==b2)
	{
	LinkedList ll1=new LinkedList();
	s1=t1.getText();
	s2=t2.getText();
	s3=t3.getText();
	s4=t4.getText();
	s5=t5.getText();
	ll1.add(s1);
	ll1.add(s2);
	ll1.add(s3);
	ll1.add(s4);
	ll1.add(s5);
	ll.add(ll1);
	t1.setText("");
	t2.setText("");
	t3.setText("");
	t4.setText("");
	t5.setText("");
	}

	else if(ae.getSource()==b3)
	{
	String str1;
	String str2;
	int i,j=0;
	LinkedList ll2=new LinkedList();
	str1=t1.getText();

	for(i=0;i<ll.size();i++)
	{
		ll2=(LinkedList)ll.get(i);
		str2=(String)ll2.getFirst();
		if(str1.equals(str2))
		{
		ll.remove(i);
		j=1;
		break;
		}
	}
	if(j==0)
	{
	t1.setText("Name Not found in the list");
	}
	if(j==1)
	{
	t1.setText("");
	t2.setText("");
	t3.setText("");
	t4.setText("");
	t5.setText("");
	}
	}

	else if(ae.getSource()==b4)
	{
	String str1;
	String str2,str3,str4,str5,str6,str;
	String g1,g2;
	int i,j=0,m1;
	LinkedList ll2=new LinkedList();
	str=t1.getText();
	str3=t2.getText();
	str4=t3.getText();
	str5=t4.getText();
	str6=t5.getText();
	if(str3.compareTo("") != 0)
	{
	str1=str;
	for(i=0;i<ll.size();i++)
	{
		ll2=(LinkedList)ll.get(i);
		str2=(String)ll2.getFirst();
		if(str1.equals(str2))
		{
		g2=(String)ll2.set(1,str3);
		j=1;
		break;
		}
	}
	}
	
	if(str4.compareTo("") != 0)
	{
	str1=str;
	for(i=0;i<ll.size();i++)
	{
		ll2=(LinkedList)ll.get(i);
		str2=(String)ll2.getFirst();
		if(str1.equals(str2))
		{
		g2=(String)ll2.set(2,str4);
		j=1;
		break;
		}
	}
	}

	if(str5.compareTo("") != 0)
	{
	str1=str;
	for(i=0;i<ll.size();i++)
	{
		ll2=(LinkedList)ll.get(i);
		str2=(String)ll2.getFirst();
		if(str1.equals(str2))
		{
		g2=(String)ll2.set(3,str5);
		j=1;
		break;
		}
	}
	}

	if(str6.compareTo("") != 0)
	{
	str1=str;
	for(i=0;i<ll.size();i++)
	{
		ll2=(LinkedList)ll.get(i);
		str2=(String)ll2.getFirst();
		if(str1.equals(str2))
		{
		g2=(String)ll2.set(4,str6);
		j=1;
		break;
		}
	}
	}

	if(j==0)
	{
	t1.setText("Name Not found in the list");
	}
	if(j==1)
	{
	t1.setText("");
	t2.setText("");
	t3.setText("");
	t4.setText("");
	t5.setText("");
	}
	}
else if(ae.getSource()==b5)
	{
	String str1;
	String str2;
	int i,j=0;
	LinkedList ll2=new LinkedList();
	str1=t1.getText();
	for(i=0;i<ll.size();i++)
	{
		ll2=(LinkedList)ll.get(i);
		str2=(String)ll2.getFirst();
		if(str1.equals(str2))
		{
		t1.setText((String)ll2.get(0));
		t2.setText((String)ll2.get(1));
		t3.setText((String)ll2.get(2));
		t4.setText((String)ll2.get(3));
		t5.setText((String)ll2.get(4));
		j=1;
		break;
		}
	}
	if(j==0)
	{
	t1.setText("Not found in the list");
	}
	}	

	
	else if(ae.getSource()==b1)
	{
	t1.setText("");
	t2.setText("");
	t3.setText("");
	t4.setText("");
	t5.setText("");
	}
}
}