db

import java.applet.*;
import java.awt.*;
/*
<applet code="DbDemo.class" height="500" width="500">
</applet>
*/
public class DbDemo extends Applet implements ActionListner
{
		Label lblname,lblroll;
		Button ins,update,del,search;
		TextField Txtnm,Txtroll;
		public void init()
		{
			lblname=new Label("enter name");
			lblroll=new Label("enter roll");


			ins=new Button("insert");
			update=new Button("update");
			del=new Button("delete");
			search=new Button("search");
			Txtnm=new TextField();
			txtroll=new TextField();
			add(lblname);
			add(Txtnm);
			add(lblroll);
			add(Txtroll);
			add(ins);
			add(update);
			add(del);
			add(search);
			ins.add ActionListner(this);
			update.add ActionListner(this);
			del.add ActionListner(this);
			search.add ActionListner(this);
		}
		public void actionPerformed(ActionEvent ae)
		{
			String lbl=ae.getActionCommand();
			String n=Txtnm.getText();
			String r=Txtroll.getText();
			if(lbl.equals("insert"))
			{

				DbMain d=new Dbmain();
				d.insert(n,r);


			}
			if(lbl.equals("update"))
			{
				DbMain d=new Dbmain();
				d.update(n,r);


			}
			if(lbl.equals("delete"))
			{
				DbMain d=new Dbmain();
				d.delete(r);


			}
			if(lbl.equals("search"))
			{
				DbMain d=new Dbmain();
				d.search();


			}
		}
}
class DbMain
{
	DbMain(){
        try
        {

         Class.forName("com.mysql.jdbc.Driver");
         Connection conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/stud?zeroDateTimeBehavior=convertToNull", "Stud",

"");
         Statement stmt=conn.createStatement();
         String query="select * from Stud";
         ResultSet rs=stmt.executeQuery(query);


        }
        catch(SQLException e1)
         {
             System.out.println("Error"+e1);
         }
         catch(ClassNotFoundException e1)
         {
             System.out.println("Error"+e1);
         }

    }
	public void search()
	{
		String query="select * from Stud";
		try
		{
			rs=stmt.executeQuery(query);
			while(rs.next())

  		      {
        		        int r=rs.getInt("Roll");
        	        	String n=rs.getString("Name");
             			System.out.println("Name="+n+"\t"+"Roll ="+r);

        	      }

		}
		catch(Exception e1)
         	{
             		System.out.println("Error"+e1);
         	}
	}
	public void insert(int r,string n)
	{
		try
		{
			String q="insert into Stud values("+r+",'"+n+";)";
			int cnt=stmt.executeUpdate(q);
			if(cnt>0)
			{ System.out.println("inserted");}
			else
			{System.out.println("not inserted");}
		}
		catch(Exception e)
		{System.out.println("error:"+e);}
	}
	public void delete(int r)
	{
		try
		{
			String q="delete from Stud where roll="+r+"";
			int cnt=stmt.executeUpdate(q);
			if(cnt>0)
			{ System.out.println("deleted");}
			else
			{System.out.println("not not deleted");}
		}
		catch(Exception e)
		{System.out.println("error:"+e);}
	}
	public void update(int r,String n)
	{
		try
		{
			String q="update Stud where set name='"+n+"' where roll="+r+"";
			int cnt=stmt.executeQuery(q);
			if(cnt>0)
			{ System.out.println("updated");}
			else
			{System.out.println("not updated");}
		}
		catch(Exception e)
		{System.out.println("error:"+e);}
	}
}