Drawing Shapes

The Graphics and Graphics2D classes provide several methods for drawing different types of shapes and figures. Here are some of the most commonly used methods:

Common Drawing Methods in Graphics and Graphics2D

  1. Lines:

    • drawLine(int x1, int y1, int x2, int y2): Draws a line between two points.

  2. Rectangles:

    • drawRect(int x, int y, int width, int height): Draws the outline of a rectangle.
    • fillRect(int x, int y, int width, int height): Fills a rectangle with the current color.

  3. Ovals:

    • drawOval(int x, int y, int width, int height): Draws the outline of an oval inscribed in the specified rectangle.
    • fillOval(int x, int y, int width, int height): Fills an oval with the current color.

  4. Arcs:

    • drawArc(int x, int y, int width, int height, int startAngle, int arcAngle): Draws the outline of an arc.
    • fillArc(int x, int y, int width, int height, int startAngle, int arcAngle): Fills an arc with the current color.

  5. Polygons:

    • drawPolygon(int[] xPoints, int[] yPoints, int nPoints): Draws the outline of a polygon defined by arrays of x and y coordinates.
    • fillPolygon(int[] xPoints, int[] yPoints, int nPoints): Fills a polygon with the current color.

  6. Round Rectangles:

    • drawRoundRect(int x, int y, int width, int height, int arcWidth, int arcHeight): Draws the outline of a rectangle with rounded corners.
    • fillRoundRect(int x, int y, int width, int height, int arcWidth, int arcHeight): Fills a rectangle with rounded corners.
Example Program to draw various shapes using Graphics
import javax.swing.*;
import java.awt.*;

public class ShapeTest extends JFrame {
    public ShapeTest() {
        setSize(400, 400);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLocationRelativeTo(null);
        setVisible(true);
    }

    public void paint(Graphics g) {
        g.drawOval(40, 40, 60, 60); // Circle
        g.drawRect(80, 30, 200, 200); // Square
        g.drawRect(200, 100, 100, 200); // Rectangle
        g.drawString("Drawing shapes", 10, 10);
        setBackground(Color.WHITE);
        g.fillRect(130, 30, 100, 80); // Rectangle
        g.drawOval(30, 130, 50, 60); // Circle
        setForeground(Color.RED);
        g.fillOval(130, 130, 50, 60); // Filled Circle
        g.drawArc(30, 200, 40, 50, 90, 60); // Arc
        g.fillArc(30, 130, 40, 50, 180, 40); // Filled Arc
    }

    public static void main(String[] args) {
        new ShapeTest();
    }
}

Setting Up the JFrame:
The ShapeTest class extends JFrame, which is a window container for GUI components.
In the constructor (ShapeTest()), we set the frame size to 400x400 pixels, set the close operation, and make it visible.

Drawing Shapes:
The paint(Graphics g) method is overridden to handle custom drawing.
We use the Graphics object (g) to draw various shapes:

g.drawOval(40, 40, 60, 60);: Draws an oval (circle) with its top-left corner at (40, 40) and dimensions 60x60 pixels.
g.drawRect(80, 30, 200, 200);: Draws a rectangle with its top-left corner at (80, 30) and dimensions 200x200 pixels.
g.drawRect(200, 100, 100, 200);: Draws another rectangle.
g.fillRect(130, 30, 100, 80);: Fills a rectangle with a white background.
g.drawOval(30, 130, 50, 60);: Draws another oval.
g.fillOval(130, 130, 50, 60);: Fills an oval with red color.
g.drawArc(30, 200, 40, 50, 90, 60);: Draws an arc (part of an ellipse).
g.fillArc(30, 130, 40, 50, 180, 40);: Fills an arc with a different angle.

Text:
g.drawString("Drawing shapes", 10, 10);: Displays the text “Drawing shapes” at coordinates (10, 10).

Colors:
We set the background color to white (setBackground(Color.WHITE)).
The foreground color (used for filling shapes) is red (setForeground(Color.RED)).

Main Method:The main method creates an instance of ShapeTest, which displays the shapes in the JFrame.

Example Program Demonstrating Various Shapes using advanced Graphics2D

Here's an example Java Swing program that demonstrates how to draw different shapes using the methods mentioned above:

import javax.swing.*;
import java.awt.*;

public class ShapesExample extends JPanel {

    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        Graphics2D g2d = (Graphics2D) g;

        // Set anti-aliasing for smoother graphics
        g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);

        // Draw a line
        g2d.setColor(Color.BLUE);
        g2d.drawLine(10, 10, 200, 10);

        // Draw a rectangle
        g2d.setColor(Color.RED);
        g2d.drawRect(10, 30, 100, 50);
        g2d.fillRect(120, 30, 100, 50);

        // Draw an oval
        g2d.setColor(Color.GREEN);
        g2d.drawOval(10, 90, 100, 50);
        g2d.fillOval(120, 90, 100, 50);

        // Draw an arc
        g2d.setColor(Color.ORANGE);
        g2d.drawArc(10, 150, 100, 100, 0, 180);
        g2d.fillArc(120, 150, 100, 100, 0, 180);

        // Draw a polygon
        int[] xPoints = {10, 60, 110};
        int[] yPoints = {300, 250, 300};
        g2d.setColor(Color.MAGENTA);
        g2d.drawPolygon(xPoints, yPoints, 3);
        g2d.fillPolygon(new int[]{120, 170, 220}, new int[]{300, 250, 300}, 3);

        // Draw a round rectangle
        g2d.setColor(Color.CYAN);
        g2d.drawRoundRect(10, 320, 100, 50, 20, 20);
        g2d.fillRoundRect(120, 320, 100, 50, 20, 20);
    }

    private static void createAndShowGUI() {
        JFrame frame = new JFrame("Shapes Example");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(300, 400);
        frame.add(new ShapesExample());
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(ShapesExample::createAndShowGUI);
    }
}

Explanation

  1. ShapesExample Panel:

    • Extends JPanel and overrides the paintComponent method.
    • Uses Graphics2D for better control and rendering quality.
    • Draws various shapes: line, rectangle, oval, arc, polygon, and round rectangle.

  2. Running the Application:

    • The createAndShowGUI method sets up the frame and adds the ShapesExample panel.
    • The main method uses SwingUtilities.invokeLater to ensure the GUI creation and updates are handled on the Event Dispatch Thread.

Comments

Post a Comment

Popular posts from this blog

KTU OOP LAB JAVA CSL 203 BTech CS S3 - Dr Binu V P

About Me Scheme and Evaluation Syllabus and Practice Questions ******************************** How to do Java Programs in  Debian PART A Basic Java Programs Using Control  Statements 1.String Problems 2.Numerical Problems 3.Arrays 4.Matrix Lab Exercise Java-1 PART B  Object Oriented Programming 1.Creating classes and objects. constructor for initializing object 2.Method overloading in Java 3.Single Inheritance 4.Multilevel Inheritance 5.Method overriding in Java 6. Hierarchical Inheritance 7.Interface in Java 8.Abstract classes in java  PART C Exception and File Handling 1.Exception Handling in Java 2.Reading and Writing Text Files 3.Buffered Reader and String Tokenizer PART D Multi-Threading  Creating Threads in Java Thread Synchronization in Java Thread Priorities in Java Programs using Multi-Threading PART E Graphics and Database Programming Introduction to Java Swing Drawing Shapes Drawing  a Sine Wave Handling Mouse Events Handling Keyboard ...
Read more

Reading and Writing Text Files

Handling text files in Java involves performing operations like reading from, writing to, and appending to files. Here are some common techniques and examples for handling text files in Java: FileReader and BufferedReader are classes in Java used for reading text from files. Here’s a detailed explanation of each: FileReader FileReader is a class in Java that is used to read character files. It is a convenient class for reading text files using the default character encoding of the operating system. Key Points: Purpose : To read text files. Inheritance : It extends InputStreamReader , which in turn extends Reader . Encoding : Uses the default character encoding of the operating system unless specified otherwise. Basic Usage : Suitable for simple file reading tasks. Example: create a text file "example.txt" using any text editor and then run this program.In this example, FileReader reads the file character by character. import java.io.FileReader; import java.io.IOException; ...
Read more

String Problems

Reverse a String import java.util.Scanner; public class ReverseString { public static void main(String[] args) {      Scanner scanner = new Scanner(System.in);      System.out.print("Enter a string to reverse: ");      String input = scanner.nextLine();      String reversed = new StringBuilder(input).reverse().toString();      System.out.println("Reversed string: " + reversed);      scanner.close(); } } without using StringBuilder import java.util.Scanner; public class ReverseString {     public static void main(String[] args) {         Scanner scanner = new Scanner(System.in);         System.out.print("Enter a string to reverse: ");         String input = scanner.nextLine();         // Manually reverse the string         String reversed = "";         for (int i = input....
Read more