Graphics programming; Frame, Components ,working with 2D shapes

Introduction to Java Graphics Programming

Java provides a powerful Abstract Window Toolkit (AWT) and Swing libraries for developing Graphical User Interfaces (GUIs). The java.awt.Graphics class is fundamental for drawing 2D shapes, handling colors, fonts, and rendering images.

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Working with Frame and Components

✳️ Frame:

A top-level window with a title and a border.

✳️ Component:

An object having a graphical representation that can be displayed on the screen and can interact with the user.

🔹 Example: Creating a Frame and Drawing a Line

Program:

import java.awt.*;

public class SimpleFrame extends Frame {

    public SimpleFrame() {

        setTitle("Basic Frame Example");

        setSize(400, 300);

        setVisible(true);

    }

 

    public void paint(Graphics g) {

        g.drawLine(50, 50, 250, 250);

    }

 

    public static void main(String[] args) {

        new SimpleFrame();

    }

}

Output:

📝 Note: The paint(Graphics g) method is overridden to draw on the frame.

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Working with 2D Shapes

Java offers the Graphics2D class for enhanced 2D rendering using shapes like rectangle, ellipse, arc, etc.

🔹 Example: Drawing Basic Shapes

Program:

import java.awt.*;

import java.awt.geom.*;

public class ShapesDemo extends Frame {

 

    public ShapesDemo() {

        setTitle("2D Shapes Example");

        setSize(400, 300);

        setVisible(true);

    }

 

    public void paint(Graphics g) {

        Graphics2D g2 = (Graphics2D) g;

 

        g2.draw(new Rectangle2D.Double(50, 50, 100, 60));

        g2.draw(new Ellipse2D.Double(200, 50, 100, 60));

        g2.draw(new Arc2D.Double(50, 150, 100, 60, 45, 90, Arc2D.OPEN));

    }

 

    public static void main(String[] args) {

        new ShapesDemo();

    }

}

Output:

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Using Color in Graphics

The setColor(Color c) method is used to set the current drawing color.

🔹 Example: Filling Shapes with Color

Program:

import java.awt.*;

import java.awt.geom.*;

 

public class ColorExample extends Frame {

    public ColorExample() {

        setTitle("Using Colors");

        setSize(400, 300);

        setVisible(true);

    }

 

    public void paint(Graphics g) {

        Graphics2D g2 = (Graphics2D) g;

        g2.setColor(Color.RED);

        g2.fill(new Rectangle2D.Double(50, 50, 100, 60));

 

        g2.setColor(new Color(0, 128, 255)); // Custom color

        g2.fill(new Ellipse2D.Double(200, 50, 100, 60));

    }

 

    public static void main(String[] args) {

        new ColorExample();

    }

}

Output:

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5. Using Fonts in Graphics

Java allows font customization using Font class and drawing text using drawString() method.

Program:

import java.awt.*; 

public class FontExample extends Frame {

    public FontExample() {

        setTitle("Font Example");

        setSize(400, 300);

        setVisible(true);

    }

 

    public void paint(Graphics g) {

        g.setFont(new Font("Serif", Font.BOLD, 24));

        g.setColor(Color.BLUE);

        g.drawString("Graphics with Font", 100, 100);

    }

 

    public static void main(String[] args) {

        new FontExample();

    }

}

Output:

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6. Working with Images

To display an image, we use the drawImage() method of the Graphics class. Images can be loaded using Toolkit.

🔹 Example: Displaying an Image

Program:

import java.awt.*; 

public class ImageExample extends Frame {

    Image img;

    public ImageExample() {

        setTitle("Image Display");

        setSize(400, 300);

        setVisible(true);

        img = Toolkit.getDefaultToolkit().getImage("your_image.jpg"); // Replace with image path

    }

    public void paint(Graphics g) {

        g.drawImage(img, 50, 50, this);

    }

    public static void main(String[] args) {

        new ImageExample();

    }

}

Output:

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🧾 Summary Notes

Topic	Description
Frame	A top-level window in AWT; used for GUI apps.
Component	Elements like Button, Label, etc.
Graphics	Core class for drawing basic shapes.
Graphics2D	Advanced class to draw geometric primitives.
Color	Used to set drawing color; predefined and custom.
Font	Customizes text style and size in graphics.
Image	Used to load and render images onto the GUI.