JSwing | Create a Magnifying tool using Java Robot

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Java Robot is a part of Java AWT (Abstract Window Toolkit ) package . Java Robot is used to generate native system input events for the purposes of test automation, self-running demos, and other applications where control of the mouse and keyboard is needed. The purpose of using Java Robot is to gain the control of input events such as mouse, keyboard etc.
In this article we will create a Magnifying toolusing JAVA Robot .
Methods used :

getPointerInfo() : Returns a PointerInfo instance that represents the current location of the mouse pointer.
getLocation() : returns a point instance that represents location
createScreenCapture(Rectangle r) : captures a part of screen which is within the rectangle r.
drawImage(Image i, int x, int y, ImageObserver o) : draws an image at x, y position on the screen specifying an image observer
drawImage(Image i, int x, int y,,int w, int h, ImageObserver o) : draws an image at x, y position and specified width and height on the screen specifying an image observer

Java program to create a Magnifying tool using Java Robot

Java

// Java program to create a Magnifying tool
// using Java Robot
 
import java.awt.event.*;
import javax.swing.*;
import java.awt.*;
class magnify extends JFrame {
 
    // object
    static magnify m;
 
    // image
    Image i;
 
    // default constructor
    magnify()
    {
        // create a frame
        super("magnify");
 
        // set size of frame
        setSize(200, 220);
        show();
 
        // function to magnify the image
        work();
    }
 
    // main function
    public static void main(String args[])
    {
 
        // object of class
        m = new magnify();
    }
 
    public void work()
    {
        try {
            // create a robot
            Robot r = new Robot();
 
            // while the frame is visible
            while (isVisible()) {
                // get the position of mouse
                Point p = MouseInfo.getPointerInfo().getLocation();
 
                // create a screen capture around the mouse pointer
                i = r.createScreenCapture(new Rectangle((int)p.getX() - 30,
                                                        (int)p.getY() - 30, 150, 150));
 
                // repaint the container
                repaint();
            }
            // exit the program
            System.exit(0);
        }
        catch (Exception e) {
            System.err.println(e.getMessage());
        }
    }
 
    // paint function
    public void paint(Graphics g)
    {
 
        // draw the image
        g.drawImage(i, 0, 0, 300, 300, this);
    }
}