TODO SWING CALCULADORA METODO CORTO en 11:05

NUEVO EJEMPLO
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class CALCULADORA2 extends JApplet implements ActionListener
{
    JTextField t1,t2,t3;
    JButton suma,resta,multi,divi;
   
    public void init()
    {
        Container c=getContentPane();
        c.setLayout(new FlowLayout());
        t1=new JTextField(30);
        t2=new JTextField(30);
        t3=new JTextField(30);
        suma=new JButton("SUMAR");
        resta=new JButton("RESTA");
        multi=new JButton("MULTIPLICAR");
        divi=new JButton("DIVIDIR");
       
        suma.addActionListener(this);
        resta.addActionListener(this);
        multi.addActionListener(this);
        divi.addActionListener(this);
       
        c.add(t1);
        c.add(t2);
        c.add(t3);
        c.add(suma);
        c.add(resta);
        c.add(multi);
        c.add(divi);
           
    }//metodo init
   
   
    public void actionPerformed(ActionEvent e)
    {
        double a,b,s,r,m,d;
        if(e.getSource()==suma)
        {
            a=Double.parseDouble(t1.getText());
            b=Double.parseDouble(t2.getText());
            s=a+b;
            t3.setText(String.valueOf(s));
        }
       
        if(e.getSource()==resta)
        {
            a=Double.parseDouble(t1.getText());
            b=Double.parseDouble(t2.getText());
            r=a-b;
            t3.setText(String.valueOf(r));
        }
       
        if(e.getSource()==multi)
        {
            a=Double.parseDouble(t1.getText());
            b=Double.parseDouble(t2.getText());
            m=a*b;
            t3.setText(String.valueOf(m));
        }
       
        if(e.getSource()==divi)
        {
            a=Double.parseDouble(t1.getText());
            b=Double.parseDouble(t2.getText());
            d=a/b;
            t3.setText(String.valueOf(d));
        }
    }
}

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