Ejemplo AWT

gistfile1.java

import java.awt.*;
import java.awt.event.*;

public class DibujoPrueba extends Frame implements WindowListener,ActionListener,KeyListener {

    //ELEMENTOS DE NUESTRO FRAME
    private Label L1,L2,L3,L4,L5=null;
    private Label V1,V2,V3,V4,V5,V6=null;
    private TextField T1,T2,T3,T4,T5,T6,T7,T8=null;
    private Button calculo=null;
    private Button limpio=null;
   
    //CONSTRUCTORES
    public DibujoPrueba(){
        super();
        configurarFrame();
    }
    public DibujoPrueba(String titulo){
        super(titulo);
        configurarFrame();
    }
    public void keyPressed(KeyEvent e){

        Object ob=e.getSource();
        char tecla=e.getKeyChar();
        if(ob.equals(T1)){
            if(tecla=='\n'){
                T2.requestFocus();
            }
        }
        if(ob.equals(T2)){
            if(tecla=='\n'){
                T3.requestFocus();
            }
        }
        if(ob.equals(T3)){
            if(tecla=='\n'){
                T4.requestFocus();
            }
        }
        if(ob.equals(T4)){
            if(tecla=='\n'){
                T5.requestFocus();
            }
        }
        if(ob.equals(T5)){
            if(tecla=='\n'){
                T6.requestFocus();
            }
        }
        if(ob.equals(T6)){
            if(tecla=='\n'){
                calcular();
            }
        }
    }
    public void keyReleased(KeyEvent e){}
    public void keyTyped(KeyEvent e){}

    public void aclarar(){
        T1.setText("");
        T2.setText("");
        T3.setText("");
        T4.setText("");
        T5.setText("");
        T6.setText("");
        T7.setText("");
        T8.setText("");
    }

    public void calcular(){
        double x1=0;
        double y1=0;
        double x2=0;
        double y2=0;
        double x3=0;
        double y3=0;

        x1=Double.valueOf(T1.getText()).doubleValue();
        y1=Double.valueOf(T2.getText()).doubleValue();
        x2=Double.valueOf(T3.getText()).doubleValue();
        y2=Double.valueOf(T4.getText()).doubleValue();
        x3=Double.valueOf(T5.getText()).doubleValue();
        y3=Double.valueOf(T6.getText()).doubleValue();

        double area=Math.abs((0.5)*(y1*(x2-x3) + y2*(x3-x1) + y3*(x1-x2)));
        double lado1=Math.sqrt((x1-x2)*(x1-x2) + (y1-y2)*(y1-y2));
        double lado2=Math.sqrt((x2-x3)*(x2-x3) + (y2-y3)*(y2-y3));
        double lado3=Math.sqrt((x1-x3)*(x1-x3) + (y1-y3)*(y1-y3));
        double perimetro=lado1+lado2+lado3;

        T7.setText(String.valueOf(area));
        T8.setText(String.valueOf(perimetro));
               
    }

    public void actionPerformed(ActionEvent e){
        Object ob=e.getSource();
        if(ob.equals(calculo)){
            calcular();
        }
        else if(ob.equals(limpio)){
            aclarar();
        }
    }

    public static void main(java.lang.String[]args){
        DibujoPrueba D1=new DibujoPrueba();
        D1.show();
    }
    private void configurarFrame(){
        this.addWindowListener(this);
        this.setLayout(null);
        this.setBackground(Color.BLUE);
        this.setResizable(true);

        L1=new Label("VERTICE 1");
        L1.setBounds(20,40,70,20);
        add(L1);

        L2=new Label("VERTICE 2");
        L2.setBounds(20,60,70,20);
        add(L2);

        L3=new Label("VERTICE 3");
        L3.setBounds(20,80,70,20);
        add(L3);

        L4=new Label("AREA");
        L4.setBounds(20,120,70,20);
        add(L4);

        L5=new Label("PERIMETRO");
        L5.setBounds(20,140,80,20);
        add(L5);

        V1=new Label("X1");
        V1.setBounds(160,40,100,20);
        add(V1);

        V2=new Label("Y1");
        V2.setBounds(450,40,100,20);
        add(V2);

        V3=new Label("X2");
        V3.setBounds(160,60,100,20);
        add(V3);

        V4=new Label("Y2");
        V4.setBounds(450,60,100,20);
        add(V4);

        V5=new Label("X3");
        V5.setBounds(160,80,100,20);
        add(V5);

        V6=new Label("Y3");
        V6.setBounds(450,80,100,20);
        add(V6);

        T1=new TextField();
        T1.setBounds(270,40,80,20);
        T1.addKeyListener(this);
        add(T1);

        T2=new TextField();
        T2.setBounds(560,40,80,20);
        T2.addKeyListener(this);
        add(T2);

        T3=new TextField();
        T3.setBounds(270,60,80,20);
        T3.addKeyListener(this);
        add(T3);

        T4=new TextField();
        T4.setBounds(560,60,80,20);
        T4.addKeyListener(this);
        add(T4);

        T5=new TextField();
        T5.setBounds(270,80,80,20);
        T5.addKeyListener(this);
        add(T5);

        T6=new TextField();
        T6.setBounds(560,80,80,20);
        T6.addKeyListener(this);
        add(T6);

        T7=new TextField();
        T7.setBounds(140,120,100,20);
        T7.addKeyListener(this);
        add(T7);

        T8=new TextField();
        T8.setBounds(140,140,100,20);
        T8.addKeyListener(this);
        add(T8);

        calculo=new Button("CALCULAR");
        calculo.setBounds(20,160,100,20);
        calculo.addActionListener(this);
        add(calculo);

        limpio=new Button("RESET");
        limpio.setBounds(20,180,100,20);
        limpio.addActionListener(this);
        add(limpio);

        setSize(700,210);
        setLocation(200,200);

    }
    public void windowActivated(WindowEvent e){}
    public void windowClosed(WindowEvent e){}
    public void windowClosing(WindowEvent e){
        Window w=e.getWindow();
        if(w.equals(this)){
            this.dispose();
            System.exit(0);
        }
    }
    public void windowDeactivated(WindowEvent e){}
    public void windowDeiconified(WindowEvent e){}
    public void windowIconified(WindowEvent e){}
    public void windowOpened(WindowEvent e){}
}