What is the use of Rectangle class in java?

Hi friends,

I just completed core java programming and started advanced java programming. For me the advanced java seems very tough than core java. In which I am not getting the use of Rectangle class. If you posses good knowledge about the Rectangle class of java programming, then please let me know that. I would greatly appreciate you help over Rectangle class.

A Rectangle class specifies an area in a coordinate space that is enclosed by the Rectangle object's top-left point (x, y) in the coordinate space, its width, and its height.A Rectangle object's width and height are public fields. The constructors that create a Rectangle, and the methods that can modify one, do not prevent setting a negative value for width or height. A Rectangle whose width or height is negative is considered empty.

Following java code will depict you about the use of Rectangle class:

Code:

---

java.awt.Rectangle;
import javax.swing.JComponent;

class RectDemo
{
  public void paint(Graphics g)
 {
    g.drawRect (20, 20, 200, 200); 
  }
}
public class DrawRect
{
  public static void main(String[] agh)
{
    JFrame window1 = new JFrame();
    window1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    window1.setBounds(40, 40, 300, 300);
    window1.getContentPane().add(new RectDemo());
    window1.setVisible(true);
  }
}

---

Hello friend,

Before using Rectangle class, you should be aware about below it's constructors:

• Rectangle(Rectangle rct)
• Rectangle(Point pt, Dimension dm)
• Rectangle(Point pt)
• Rectangle(int xn, int yn, int width1, int height1)
• Rectangle(int width1, int height1)

Hi,

I suggest you to study following example of Rectangle class:

Code:

---

import java.awt.Graphics2D;
import java.awt.Rectangle;

public class RectangleTP extends JApplet {
  final static BasicStroke stroke1 = new BasicStroke(2.0f);
  public void init() {
    setBackground(Color.blue);
    setForeground(Color.blue);
  }
  public void paint(Graphics g) {
    Graphics2D g02 = (Graphics2D) g;
    g02.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
        RenderingHints.VALUE_ANTIALIAS_ON);
    g02.setPaint(Color.gray);
    int x = 5;
    int y = 7;
    g02.setStroke(stroke);
    g02.draw(new Rectangle2D.Double(x, y, 200, 200));
    g02.drawString("Rectangle2D", x, 250);
  }
  public static void main(String sko[]) {
    JFrame f1 = new JFrame("");
    f1.addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent e) {
        System.exit(0);
      }    }
    JApplet applet = new RectangleDemo2D();
    f1.getContentPane().add("Center", applet);
    f1.setSize(new Dimension(400, 300));
    f1.show();
  }
}

---

Please go through following various methods of Rectangle class of java:

1. translate(int ak, int bk)
2. setSize(int wd, int ht)
3. setRect(double ak, double bk, double wd, double ht)
4. setLocation(int ak, int bk)
5. resize(int wd, int ht