Estou tentando instanciar o objeto, de Quadirlateral pra trapezoid mas não consigo algém pode me ajudar.
[code]public class Quadrilateral extends Object{
protected double x,y;
/** Creates a new instance of Quadrilateral */
public Quadrilateral() {
setQuadrilateral(0,0);
}
public void setQuadrilateral( double x, double y){
setX( x);
setY( y);
}
public void setX( double xx){
x = ( xx >= 0 ? xx : 0);
}
public void setY( double yy){
y = ( yy >= 0 ? yy : 0);
}
public double getX(){
return x;
}
public double getY(){
return y;
}
public double area(){
return x * x * y * y;
}
public String toString(){
return "[" + x + ", " + y + "]";
}
}[/code]
[code]public class Trapezoid extends Quadrilateral{
protected double x;
protected double y;
public Trapezoid(){
x = super.getX();
y = super.getY();
}
public double area(){
return (x + y)/2;
}
public String toString(){
return (super.toString());
}
}
import java.awt.;
import java.awt.event.;
import javax.swing.*;
public class Areas extends JFrame{
private Quadrilateral quadrilateral;
private Trapezoid trapezoid;
private JLabel xLabel, yLabel;
private JTextField xField, yField,resultField, resultField1;
private JButton exitButton;
/** Creates a new instance of Areas */
public Areas() {
super( "Área");
quadrilateral = new Quadrilateral();
trapezoid = new Trapezoid();
ActionEventHandler handler = new ActionEventHandler();
Container container = getContentPane();
container.setLayout( new FlowLayout() );
xLabel = new JLabel("Coordenada x ");
xField = new JTextField(10);
xField.addActionListener( handler);
container.add( xLabel);
container.add( xField);
yLabel = new JLabel("Coordenada y ");
yField = new JTextField(10);
yField.addActionListener( handler);
container.add( yLabel);
container.add( yField);
resultField = new JTextField(20);
resultField.setEditable( false);
container.add( resultField);
resultField1 = new JTextField(20);
resultField1.setEditable( false);
container.add( resultField1);
exitButton = new JButton("Sair");
exitButton.addActionListener( handler);
container.add( exitButton);
}
public void resultTime(){
resultField.setText("Quadrilateral: " + quadrilateral.toString() + " Area: " + quadrilateral.area());
resultField1.setText(" Trapézio: " + trapezoid.toString()+ " Area: " + trapezoid.area());
}
public static void main( String args[]){
Areas window = new Areas();
window.setSize(250, 170);
window.setVisible( true);
}
private class ActionEventHandler
implements ActionListener{
public void actionPerformed( ActionEvent event){
if ( event.getSource() == exitButton)
System.exit(0);
else if ( event.getSource() == xField){
quadrilateral.setX(
Double.parseDouble( event.getActionCommand() ));
}
else if ( event.getSource() == yField){
quadrilateral.setY(
Double.parseDouble( event.getActionCommand() ));
}
resultTime();
}
}
}[/code]