TY_BCS_JAVA_SLIP 10_1

Slip 10_1. Write a program to implement simple arithmetic calculator. Perform appropriate validations.

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

public class Slip10_1  extends JFrame implements ActionListener

{

                String msg=" ";

                                int v1,v2,result;

                                JTextField t;

                                JButton b[]=new JButton[10];

                                JButton add,sub,mul,div,clear,equals;

                                char choice;

                                JPanel p,p1;

                                Slip10_1()

                                {

                                                setLayout(new BorderLayout());

                                                                p =new JPanel();

                                                                t=new JTextField(20);

                                                                p.add(t);

                                                               

                                                                p1=new JPanel();

                                                                p1.setLayout(new GridLayout(5,4));

                                                                for(int i=0;i<10;i++)

                                                                {

                                                                                b[i]=new JButton(""+i);

                                                                }

                                                equals=new JButton("=");

                                                                add=new JButton("+");

                                                                sub=new JButton("-");

                                                                mul=new JButton("*");

                                                                div=new JButton("/");

                                                                clear=new JButton("C");

                                                               

                                                                for(int i=0;i<10;i++)

                                                                {

                                                                                p1.add(b[i]);

                                                                }

                                               

                                                                p1.add(equals);

                                                                p1.add(add);

                                                                p1.add(sub);

                                                                p1.add(mul);

                                                                p1.add(div);

                                                                p1.add(clear);

                                                               

                                                                for(int i=0;i<10;i++)

                                                                {

                                                                                b[i].addActionListener(this);

                                                                }

                                                add.addActionListener(this);

                                                                sub.addActionListener(this);

                                                                mul.addActionListener(this);

                                                                div.addActionListener(this);

                                                                clear.addActionListener(this);

                                                                equals.addActionListener(this);

                                                               

                                                                add(p,BorderLayout.NORTH);

                                                                add(p1);

                                                                setVisible(true);

                                                setSize(500,500);

                                                setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);    

                               

                                }

               

                                public void actionPerformed(ActionEvent ae)

                                {

                                                String str = ae.getActionCommand();

                                                                char ch = str.charAt(0);

                                                                if ( Character.isDigit(ch))

                                                                                t.setText(t.getText()+str);

                                                                else

                                                                                if(str.equals("+"))

                                                                                {

                                                                                                v1=Integer.parseInt(t.getText());

                                                                                                                choice='+';

                                                                                                                t.setText("");

                                                                                }

                                                                                else if(str.equals("-"))

                                                                                {

                                                                                                v1=Integer.parseInt(t.getText());

                                                                                                                choice='-';

                                                                                                                t.setText("");

                                                                                }

                                                                                else if(str.equals("*"))

                                                                                {

                                                                                                v1=Integer.parseInt(t.getText());

                                                                                                                choice='*';

                                                                                                                t.setText("");

                                                                                }

                                                                                else if(str.equals("/"))

                                                                                {

                                                                                                v1=Integer.parseInt(t.getText());

                                                                                                                choice='/';

                                                                                                                t.setText("");

                                                                                }

                                               

                                                                if(str.equals("="))

                                                                {

                                                                                v2=Integer.parseInt(t.getText());

                                                                                                if(choice=='+')

                                                                                                                result=v1+v2;

                                                                                                else if(choice=='-')

                                                                                                                result=v1-v2;

                                                                                                else if(choice=='*')

                                                                                                                result=v1*v2;

                                                                                                else if(choice=='/')

                                                                                                                result=v1/v2;

                                                                                                                               

                                                                                                                                t.setText(""+result);

                                                                }             

                                                if(str.equals("C"))

                                                {

                                                                t.setText("");

                                                }

                                }

                public static void main(String a[])

                {

                                Slip10_1 ob = new Slip10_1();

                }

}