CALCULATOR PROGRAMMING USING JAVA LANGUAGE

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.io.*;
import java.util.*;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
class Calculater extends JFrame implements ActionListener
{
//-----------------------------------------------------------------------------------------
JTextField tf;
JButton b0;
JButton b1;
JButton b2;
JButton b3;
JButton b4;
JButton b5;
JButton b6;
JButton b7;
JButton b8;
JButton b9;
JButton badd;
JButton bsub;
JButton beql;
int countadd=0;
int countsub=0;
//String s[];

//int num[];
int ans=0;


//--------------------------------------------------------------------------------------------
public static void main(String cal[])throws Exception
{
Calculater calc=new Calculater();
}

Calculater()
{
tf=new JTextField();
tf.setBounds(100,50,200,40);
add(tf);
b1=new JButton("1");
b1.setBounds(100,100,45,30);
b1.addActionListener(this);
add(b1);
b2=new JButton("2");
b2.setBounds(150,100,45,30);
b2.addActionListener(this);
add(b2);
b3=new JButton("3");
b3.setBounds(200,100,45,30);
b3.addActionListener(this);
add(b3);
badd=new JButton("+");
badd.setBounds(250,100,45,30);
badd.addActionListener(this);
add(badd);
b4=new JButton("4");
b4.setBounds(100,140,45,30);
b4.addActionListener(this);
add(b4);
b5=new JButton("5");
b5.setBounds(150,140,45,30);
b5.addActionListener(this);
add(b5);
b6=new JButton("6");
b6.setBounds(200,140,45,30);
b6.addActionListener(this);
add(b6);
bsub=new JButton("-");
bsub.setBounds(250,140,45,30);
bsub.addActionListener(this);
add(bsub);
b7=new JButton("7");
b7.setBounds(100,180,45,30);
b7.addActionListener(this);
add(b7);
b8=new JButton("8");
b8.setBounds(150,180,45,30);
b8.addActionListener(this);
add(b8);
b9=new JButton("9");
b9.setBounds(200,180,45,30);
b9.addActionListener(this);
add(b9);
beql=new JButton("=");
beql.setBounds(250,180,45,30);
beql.addActionListener(this);
add(beql);
b0=new JButton("0");
b0.setBounds(150,220,45,30);
b0.addActionListener(this);
add(b0);


setSize(600,600);
setLayout(null);
setVisible(true);
}
/*public static void sep()
{
String m=tf.getText();
StringTokenizer st=new StringTokenizer(m,"+");
s=new String[countadd];
for(int i=0;i<countadd;i++)
{
s[i]=st.nextToken();
}
num=new int[countadd];
for(int j=0;j<countadd;j++)
{
num[j]=Integer.parseInt(s[j]);
}

}
public void add()
{
for(int l:num)
{
ans=ans+l;
}
tf.setText(String.valueOf(ans));
}*/
public void actionPerformed(ActionEvent e)
{ String n;

if(e.getSource()==b1)
{
n=tf.getText();
n=n+"1";
tf.setText(n);
}
if(e.getSource()==b2)
{
n=tf.getText();
n=n+"2";
tf.setText(n);
}
if(e.getSource()==b3)
{
n=tf.getText();
n=n+"3";
tf.setText(n);
}
if(e.getSource()==b4)
{
n=tf.getText();
n=n+"4";
tf.setText(n);
}
if(e.getSource()==b5)
{
n=tf.getText();
n=n+"5";
tf.setText(n);
}
if(e.getSource()==b6)
{
n=tf.getText();
n=n+"6";
tf.setText(n);
}
if(e.getSource()==b7)
{
n=tf.getText();
n=n+"7";
tf.setText(n);
}
if(e.getSource()==b8)
{
n=tf.getText();
n=n+"8";
tf.setText(n);
}
if(e.getSource()==b9)
{
n=tf.getText();
n=n+"9";
tf.setText(n);
}
if(e.getSource()==b0)
{
n=tf.getText();
n=n+"0";
tf.setText(n);
}
if(e.getSource()==badd)
{ countadd++;
System.out.println(countadd);
n=tf.getText();
n=n+"+";
tf.setText(n);
}
if(e.getSource()==bsub)
{ countsub++;
n=tf.getText();
n=n+"-";
tf.setText(n);
}
if(e.getSource()==beql)
{
String m=tf.getText();
StringTokenizer st=new StringTokenizer(m,"+");
ArrayList<String> s=new ArrayList<String>();
for(int i=0;i<=(s.size());i++)
{
s.add(st.nextToken());
System.out.println(s.get(i));
}
ArrayList<Integer> num=new ArrayList<Integer>();
for(int j=0;j<=(s.size());j++)
{
num.add(Integer.parseInt(s.get(j)));
ans=ans+num.get(j);
tf.setText(String.valueOf(ans));
}
}


}
}