Displaying Bar Charts using JFrames

Here is a Java Program to Display the bar chart using JFrames

import org.jfree.chart.*;
import org.jfree.data.category.*;
import org.jfree.data.general.DefaultPieDataset;
import org.jfree.data.xy.*;
import org.jfree.data.*;
import org.jfree.chart.renderer.category.*;
import org.jfree.chart.plot.*;
import java.awt.*;

public class BarExample1{
public static void main(String arg[]){
  DefaultCategoryDataset dataset = new DefaultCategoryDataset();
  dataset.setValue(2, "Marks", "Rahul");
  dataset.setValue(7, "Marks", "Vinod");
  dataset.setValue(4, "Marks", "Deepak");
  dataset.setValue(9, "Marks", "Prashant");
  dataset.setValue(6, "Marks", "Chandan");
  JFreeChart chart = ChartFactory.createBarChart("BarChart using JFreeChart","Student", "Marks", dataset, PlotOrientation.VERTICAL, false,true, false);
  chart.setBackgroundPaint(Color.yellow);
  chart.getTitle().setPaint(Color.blue); 
  CategoryPlot p = chart.getCategoryPlot(); 
  p.setRangeGridlinePaint(Color.red); 
  ChartFrame frame1=new ChartFrame("Bar Chart",chart);
  frame1.setVisible(true);
  frame1.setSize(400,350);
  }
} 

Need to add the below jar files to lib:
1. jcommon-1.0.14
2. jfreechart-1.0.11

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Make BullsEye Target Using Java AWT and Swing Classes

Here is a Java Program to Make BullsEye Target Using Java AWT and Swing Classes

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

class BullseyeDemo {
 
    public static void main(String[] args) {
        JFrame target = new BullseyeWindow();
        target.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        target.setVisible(true);
    }
}

class BullseyeWindow extends JFrame {
    int initialRings = 10; // Number of rings to start with.
    Bullseye be;           // The panel that draws the bullseye

    public BullseyeWindow() {
        JSlider slide = new JSlider(JSlider.HORIZONTAL, 0, 30, initialRings);
        slide.setMajorTickSpacing(5); // sets numbers for biggest tick marks
        slide.setPaintLabels(true);   // display numbers on major ticks
        slide.setMinorTickSpacing(1); // smaller tick marks
        slide.setPaintTicks(true);    // display the ticks
        slide.addChangeListener(new ChangeListener() {
                public void stateChanged(ChangeEvent e) {
                    int num = ((JSlider)(e.getSource())).getValue();
                    be.setRings(num);
                }
            });

        be = new Bullseye();
        be.setRings(initialRings);

        Container content = this.getContentPane();
        content.setLayout(new BoxLayout(content, BoxLayout.Y_AXIS));
        content.add(slide);
        content.add(be);
        
        this.setTitle("BullseyeDemo");
        this.pack();
        this.setResizable(false);
    }
}


class Bullseye extends JPanel {
    static final int SIZE = 300; // initial window size
    int rings = 5;  // Number of rings to draw in bullseye

    public Bullseye() {
        this.setBackground(Color.white);
        this.setPreferredSize(new Dimension(SIZE, SIZE));
    }
    
    public void setRings(int r) {
        rings = r;
        this.repaint();  // new value of rings - better repaint
    }
    
    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        int x = SIZE/2;  // x,y of top left corner for drawing circles
        int y = SIZE/2;
        
        for (int i=rings; i>0; i--) {
            if (i%2 == 0) {
                g.setColor(Color.red);
            } else {
                g.setColor(Color.blue);
            }
            int radius = i * 100/rings;  // compute radius of this ring
            g.fillOval(x-radius, y-radius, radius*2, radius*2);
        }
    }
}

Output of Above Java Program

On Running The Program

When Move Slider to 24

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Find the Body Mass Index Using AWT and Swing Classes

Here is a Java Program to Find the Body Mass Index Using AWT and Swing Classes

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

class BMI extends JFrame {
    public static void main(String[] args) {
        BMI window = new BMI();
        window.setVisible(true);
    }


    private JTextField _mField   = new JTextField(4);  // height
    private JTextField _kgField  = new JTextField(4);  // weight
    private JTextField _bmiField = new JTextField(4);  // BMI

    /****************constructor********************/
    public BMI() {
        //Create button and add action listener.
        JButton bmiButton = new JButton("Compute BMI");
        bmiButton.addActionListener(new BMIListener());

        //Set layout and add components.
        JPanel content = new JPanel();
        content.setLayout(new FlowLayout());
        content.add(new JLabel("Weight in kilograms"));
        content.add(_kgField);
        content.add(new JLabel("Height in meters"));
        content.add(_mField);
        content.add(bmiButton);
        content.add(new JLabel("Your BMI is"));
        content.add(_bmiField);

        //Set the window characteristics.
        setContentPane(content);
        setTitle("Body Mass Index");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        pack();                          // Do layout.
        setLocationRelativeTo(null);     // Center window.
    }

    /******************* inner class BMIListener *********************/
    // Inner class is used to access components.
    // BMI is converted to int to eliminate excess "accuracy".
    private class BMIListener implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            double kilograms = Double.parseDouble(_kgField.getText());
            double meters    = Double.parseDouble(_mField.getText());
            int    bmi       = (int)computeBMI(kilograms, meters);
            _bmiField.setText("" + bmi);
        }
    }

    //logic method computeBMI
    public static double computeBMI(double weight, double height) {
        return weight / (height * height);
    }
}

Output of Above Java Program

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