Draw General Path

import java.awt.*;
import javax.swing.*;
import java.awt.geom.*;
import java.util.Vector;

public class ShowGeneralPath extends JApplet {
Canvas1 canvas;

public static void main(String[] args) {
    JFrame frame = new JFrame("Show General Paths");
    ShowGeneralPath path = new ShowGeneralPath();
    path.init();
    frame.getContentPane().add(path);
    frame.setSize(280, 250);
    frame.show();
  }
    public void init() {
    Container container = getContentPane();
    JPanel panel = new JPanel();
    canvas = new Canvas1();
    container.add(canvas);
  }
    class Canvas1 extends Canvas {
    Vector generalPath;

    public Canvas1() {
      setBackground(Color.white);
      setSize(400, 200);
      generalPath = new Vector();
      GeneralPath path1, path2,path3;

      path1 = new GeneralPath();
      path1.moveTo(25, 35);
      path1.lineTo(35, 50);
      path1.lineTo(50, 20);
      path1.lineTo(80, 30);
    path1.curveTo(20, 100, 110, 60, 40, 100);
      generalPath.addElement(path1);

      path2 = new GeneralPath();
      path2.moveTo(120, 20);
      path2.lineTo(120, 80);
      path2.lineTo(180, 20);
      path2.lineTo(180, 80);
      path2.closePath();
      generalPath.addElement(path2);

    path3 = new GeneralPath();
      path3.moveTo(50, 120);
      path3.lineTo(70, 180);
      path3.lineTo(20, 140);
      path3.lineTo(80, 140);
      path3.lineTo(30, 180);
      path3.closePath();
      generalPath.addElement(path3);
   }
    public void paint(Graphics g) {
      Graphics2D g2d = (Graphics2D) g;
     for (int i = 0; i < generalPath.size(); i++) {
          g2d.setPaint(Color.red);
          g2d.draw((GeneralPath) generalPath.elementAt(i));
        }
    }
  }
}

Polygon in Java

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

public class DrawPolygon extends JPanel {
  public void paintComponent(Graphics g) {
    super.paintComponent(g);
  g.setColor(Color.red);
     Polygon polygon1= new Polygon();
     for (int i = 0; i < 3; i++){
      polygon1.addPoint((int) (40 + 50 * Math.cos(i * 2 * Math.PI / 3)),
          (int) (150 + 50 * Math.sin(i * 2 * Math.PI / 3)));
   }
   g.drawPolygon(polygon1);

     Polygon polygon2= new Polygon();
     for (int i = 0; i < 6; i++){
      polygon2.addPoint((int) (160 + 50 * Math.cos(i * 2 * Math.PI / 6)),
          (int) (150 + 50 * Math.sin(i * 2 * Math.PI / 6)));
   }
   g.drawPolygon(polygon2);

    Polygon polygon3 = new Polygon();
 
     for (int i = 0; i < 360; i++) {
      double value = i / 360.0;
      polygon3.addPoint((int) (290 + 50 * value * Math.cos(8 * value * Math.PI)),
          (int) (150 + 50 * value * Math.sin(8 * value * Math.PI)));
   }
      g.drawPolygon(polygon3);
   }
 
  public static void main(String[] args) {
    JFrame frame = new JFrame();
    frame.setTitle("Show Different Polygons");
    frame.setSize(350, 250);
    Container contentPane = frame.getContentPane();
    contentPane.add(new DrawPolygon());
    frame.show();
  }
}

Draw An Arc in java

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

public class DrawAnArc extends JApplet {
  BasicStroke basicStroke = new BasicStroke(5.0f); 
    public void paint(Graphics g) {
    Graphics2D g2d = (Graphics2D) g;
    g2d.setPaint(Color.red);
    g2d.setStroke(basicStroke);
    g2d.draw(new Arc2D.Double(5, 10, 150, 150, 60, 150,
        Arc2D.OPEN));
    }
  public static void main(String s[]) {
    JFrame frame = new JFrame("Draw Arc");
    JApplet applet = new DrawAnArc();
    frame.getContentPane().add("Center", applet);
    frame.setSize(300, 250);
    frame.show();
  }
}

Ellipse in Rectangle

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

public class DrawRectangleAndEllipse extends JApplet {
  final static BasicStroke stroke = new BasicStroke(2.0f);
  public void init() {
    setBackground(Color.white);
    setForeground(Color.white);
  }
  public void paint(Graphics g) {
    Graphics2D g2 = (Graphics2D) g;
    g2.setPaint(Color.red);
    int x = 6;
    int y = 8;
    g2.setStroke(stroke);
    g2.draw(new Rectangle2D.Double(x, y, 150, 150));
  g2.draw(new Ellipse2D.Double(x, y, 150, 150));
    }
  public static void main(String args[]) {
    JFrame frame = new JFrame("Draw Ellipse inside Rectangle");
    JApplet applet = new DrawRectangleAndEllipse();
    frame.getContentPane().add("Center", applet);
    applet.init();
    frame.setSize(250, 200);
    frame.show();
  }
}

Draw Triangle using Lines

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.awt.geom.Line2D;

public class DrawTriangleUsingLine2D extends JApplet {
    public void init() {
    setBackground(Color.lightGray);
  }
    public void paint(Graphics g) {
    Graphics2D g2d = (Graphics2D) g;
    g2d.setPaint(Color.red);
    g2d.draw(new Line2D.Double(50,150,150,150 ));
  g2d.draw(new Line2D.Double(50,50,150,150 ));
  g2d.draw(new Line2D.Double(50,50,50,150 ));
    }
    public static void main(String s[]) {
    JFrame frame = new JFrame("Show Triangle");
    JApplet applet = new DrawTriangleUsingLine2D();
    frame.getContentPane().add("Center", applet);
    applet.init();
    frame.setSize(300, 250);
    frame.show();
  }
}