Design and Implement GPA Calculator

Once the user clicks on the calculate button the program should display on a dialog box first the info about the student like his name. ID, session and student type. Second the program should display the GPA.

Once the user clicks on the clear button all the fields in the form should be cleared. Once the user clicks on the cancel button the program should stop.

Assume that all the courses have the same credits number which is: 3

The points for the letter grades are as follows:

A 4 B+ 3.5 B 3 c+ 2.5 C 2 D+ 1.5 D 1 F 0

the user should be able to enter the letter grades in lower or upper cases like A or a.

View Answers

June 14, 2013 at 10:38 AM

Try the following code snippet, may this will be helpful for you.

import javax.swing.*;

import java.awt.*;
import java.awt.event.*;

public class GPACalculator {

    JFrame frame;   
    JInternalFrame jInternalFrame;
    JLabel headingLabel, stuNameLabel, stuIdLabel, sessionLabel, 
    stuType, courseLabel1, courseLabel2, courseLabel3, courseLabel4, 
    courseLabel5, courseLabel6;
    JCheckBox eveningCheckbox, morningCheckbox;
    JRadioButton regularRdbtn, nonDegreeRdbtn;
    JTextField course1, course2, course3, course4, course5, course6,
    stuNameTf, stuIdTf;
    JButton calculate, clear, cancel;
    JDesktopPane desktop = new JDesktopPane();

    public void createUI()
    {
        frame = new JFrame("GPA Calculator");
        //frame.setLayout(new BorderLayout());
        frame.setLayout(null);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        headingLabel = new JLabel("Welcome To GPA Calculator");
        headingLabel.setBounds(10, 10, 200, 20);

        stuNameLabel = new JLabel("Student Name");
        stuNameLabel.setBounds(30, 30, 100, 20);

        stuNameTf = new JTextField();
        stuNameTf.setBounds(130, 30, 100, 20);

        stuIdLabel = new JLabel("ID");
        stuIdLabel.setBounds(270, 30, 20, 20);

        stuIdTf = new JTextField();
        stuIdTf.setBounds(290, 30, 100, 20);

        sessionLabel = new JLabel("Session");
        sessionLabel.setBounds(30, 60, 80, 20);

        eveningCheckbox = new JCheckBox("Evening");
        eveningCheckbox.setBounds(110, 60, 80, 20);

        morningCheckbox = new JCheckBox("Morning");
        morningCheckbox.setBounds(190, 60, 80, 20);

        stuType = new JLabel("Student Type");
        stuType.setBounds(30, 90, 80, 20);

        regularRdbtn = new JRadioButton("regular");
        regularRdbtn.setBounds(110, 90, 80, 20);

        nonDegreeRdbtn = new JRadioButton("non Degree");
        nonDegreeRdbtn.setBounds(190, 90, 100, 20);

        courseLabel1 = new JLabel("Course1");
        courseLabel1.setBounds(30, 120, 60, 20);

        course1 = new JTextField();
        course1.setBounds(90, 120, 100, 20);

        courseLabel2 = new JLabel("Course2");
        courseLabel2.setBounds(200, 120, 60, 20);

        course2 = new JTextField();
        course2.setBounds(260, 120, 100, 20);

        courseLabel3 = new JLabel("Course3");
        courseLabel3.setBounds(30, 150, 60, 20);

        course3 = new JTextField();
        course3.setBounds(90, 150, 100, 20);

        courseLabel4 = new JLabel("Course4");
        courseLabel4.setBounds(200, 150, 60, 20);

        course4 = new JTextField();
        course4.setBounds(260, 150, 100, 20);

        courseLabel5 = new JLabel("Course5");
        courseLabel5.setBounds(30, 180, 60, 20);

        course5 = new JTextField();
        course5.setBounds(90, 180, 100, 20);

        courseLabel6 = new JLabel("Course6");
        courseLabel6.setBounds(200, 180, 60, 20);

        course6 = new JTextField();
        course6.setBounds(260, 180, 100, 20);

Continue...

June 14, 2013 at 10:38 AM

calculate = new JButton("Calculate");
        calculate.setBounds(80, 230, 100, 20);
        calculate.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent ae)
            {
                displayStudentRecord();
            }
        });

        clear = new JButton("Clear");
        clear.setBounds(190, 230, 80, 20);
        clear.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent ae)
            {
                resetFields();
            }
        });

        cancel = new JButton("Cancel");
        cancel.setBounds(280, 230, 80, 20);
        cancel.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent ae)
            {
                closeFrame();
            }
        });     

        frame.add(headingLabel);
        frame.add(stuNameLabel);
        frame.add(stuNameTf);
        frame.add(stuIdLabel);
        frame.add(stuIdTf);
        frame.add(sessionLabel);
        frame.add(eveningCheckbox);
        frame.add(morningCheckbox);
        frame.add(stuType);
        frame.add(regularRdbtn);
        frame.add(nonDegreeRdbtn);
        frame.add(courseLabel1);
        frame.add(course1);
        frame.add(courseLabel2);
        frame.add(course2);
        frame.add(courseLabel3);
        frame.add(course3);
        frame.add(courseLabel4);
        frame.add(course4);
        frame.add(courseLabel5);
        frame.add(course5);
        frame.add(courseLabel6);
        frame.add(course6);
        frame.add(calculate);       
        frame.add(clear);
        frame.add(cancel);

        frame.pack();
        frame.setVisible(true);
        frame.setSize(500,400);
    }

June 14, 2013 at 10:39 AM

public JCheckBox checkboxName()
    {
        JCheckBox ckbox = null;
        if(eveningCheckbox.isSelected())
        {
            ckbox = eveningCheckbox;
        }
        else if(morningCheckbox.isSelected())
        {
            ckbox = morningCheckbox;
        }

        return ckbox;
    }

    public JRadioButton radioButtonName()
    {
        JRadioButton radioBtn = null;
        if(regularRdbtn.isSelected())
        {
            radioBtn = regularRdbtn;
        }
        else if(nonDegreeRdbtn.isSelected())
        {
            radioBtn = nonDegreeRdbtn;
        }

        return radioBtn;
    }

June 14, 2013 at 10:40 AM

Continue...

public String getGPA()
    {
        double A = 0, BP = 0, B = 0, CP = 0, C = 0, DP = 0, D = 0, F = 0;
        double avg = 0, total=0;
        String gpa = "";
        String grade ="";
        String c1 = course1.getText();
        String c2 = course2.getText();
        String c3 = course3.getText();
        String c4 = course4.getText();
        String c5 = course5.getText();
        String c6 = course6.getText();      

        if(c1.equalsIgnoreCase("a") 
                || c2.equalsIgnoreCase("a")
                || c3.equalsIgnoreCase("a") 
                || c4.equalsIgnoreCase("a")
                || c5.equalsIgnoreCase("a")
                || c6.equalsIgnoreCase("a"))
        {
            A = 4;
        }
        else if(c1.equalsIgnoreCase("b+")
                || c2.equalsIgnoreCase("b+")
                || c3.equalsIgnoreCase("b+")
                || c4.equalsIgnoreCase("b+")
                || c5.equalsIgnoreCase("b+")
                || c6.equalsIgnoreCase("b+"))
        {
            BP = 3.5;
        }
        else if(c1.equalsIgnoreCase("b")
                || c2.equalsIgnoreCase("b")
                || c3.equalsIgnoreCase("b")
                || c4.equalsIgnoreCase("b")
                || c5.equalsIgnoreCase("b")
                || c6.equalsIgnoreCase("b"))
        {
            B = 3;
        }
        else if(c1.equalsIgnoreCase("c+")
                || c2.equalsIgnoreCase("c+")
                || c3.equalsIgnoreCase("c+")
                || c4.equalsIgnoreCase("c+")
                || c5.equalsIgnoreCase("c+")
                || c6.equalsIgnoreCase("c+"))
        {
            CP = 2.5;
        }
        else if(c1.equalsIgnoreCase("c")
                || c2.equalsIgnoreCase("c")
                || c3.equalsIgnoreCase("c")
                || c4.equalsIgnoreCase("c")
                || c5.equalsIgnoreCase("c")
                || c6.equalsIgnoreCase("c"))
        {
            C = 2;
        }
        else if(c1.equalsIgnoreCase("d+")
                || c2.equalsIgnoreCase("d+")
                || c3.equalsIgnoreCase("d+")
                || c4.equalsIgnoreCase("d+")
                || c5.equalsIgnoreCase("d+")
                || c6.equalsIgnoreCase("d+"))
        {
            DP = 1.5;
        }
        else if(c1.equalsIgnoreCase("d")
                || c2.equalsIgnoreCase("d")
                || c3.equalsIgnoreCase("d")
                || c4.equalsIgnoreCase("d")
                || c5.equalsIgnoreCase("d")
                || c6.equalsIgnoreCase("d"))
        {
            D = 1;
        }
        else if(c1.equalsIgnoreCase("f")
                || c2.equalsIgnoreCase("f")
                || c3.equalsIgnoreCase("f")
                || c4.equalsIgnoreCase("f")
                || c5.equalsIgnoreCase("f")
                || c6.equalsIgnoreCase("f"))
        {
            F = 0;
        }

        avg = A+BP+B+CP+C+DP+D+F;
        if(avg >= 4)
        {
            gpa = "A";
        }
        if(avg < 4 && avg >=3.5)
        {
            gpa = "B+";
        }
        if(avg < 3.5 && avg >= 3)
        {
            gpa = "B";
        }
        if(avg < 3 && avg >= 2.5)
        {
            gpa = "C+";
        }
        if(avg < 2.5 && avg >= 2)
        {
            gpa = "C";
        }
        if(avg < 2 && avg >= 1.5)
        {
            gpa = "D+";
        }
        if(avg < 1.5 && avg >=1)
        {
            gpa = "D";
        }
        if(avg < 1)
        {
            gpa = "F";
        }
        System.out.println(gpa);
        return gpa;         

    }

June 14, 2013 at 10:41 AM

Continue...

public void displayStudentRecord()
    {
        jInternalFrame = new JInternalFrame("Student Record", true, true, true, true);
        jInternalFrame.setBounds(50, 50, 400, 250);
        jInternalFrame.setVisible(true);

        String stuName = stuNameTf.getText();
        String stuId = stuIdTf.getText();
        String checkboxValue = checkboxName().getText();
        String radioBtnValue = radioButtonName().getText();
        String stuGpaValue = getGPA();

        JLabel stuNameLabel = new JLabel("Name");
        JLabel name = new JLabel();
        name.setText(stuName);
        stuNameLabel.setBounds(20, 20, 80, 20);
        name.setBounds(130, 20, 150, 20);

        JLabel stuIdLabel = new JLabel("ID");
        JLabel id = new JLabel();
        id.setText(stuId);
        stuIdLabel.setBounds(20, 40, 30, 20);
        id.setBounds(130, 40, 100, 20);

        JLabel ckLabel = new JLabel("Session");
        JLabel ckValue = new JLabel();
        ckValue.setText(checkboxValue);
        ckLabel.setBounds(20, 60, 80, 20);
        ckValue.setBounds(130, 60, 100, 20);

        JLabel rdLabel = new JLabel("Student Type");
        JLabel rdValue = new JLabel();
        rdValue.setText(radioBtnValue);
        rdLabel.setBounds(20, 80, 110, 20);
        rdValue.setBounds(130, 80, 100, 20);

        JLabel gpLabel = new JLabel("GPA");
        JLabel gpValue = new JLabel();
        gpValue.setText(stuGpaValue);
        gpLabel.setBounds(20, 100, 30, 20);
        gpValue.setBounds(130, 100, 20, 20);

        jInternalFrame.add(stuNameLabel);
        jInternalFrame.add(name);
        jInternalFrame.add(stuIdLabel);
        jInternalFrame.add(id);
        jInternalFrame.add(ckLabel);
        jInternalFrame.add(ckValue);
        jInternalFrame.add(rdLabel);
        jInternalFrame.add(rdValue);
        jInternalFrame.add(gpLabel);
        jInternalFrame.add(gpValue);

        desktop.add(jInternalFrame);
        frame.setContentPane(desktop);
        desktop.setDragMode(JDesktopPane.OUTLINE_DRAG_MODE);
    }

    public void resetFields()
    {
        stuNameTf.setText("");
        stuIdTf.setText("");
        course1.setText("");
        course2.setText("");
        course3.setText("");
        course4.setText("");
        course5.setText("");
        course6.setText("");        
    }

    public void closeFrame()
    {
        frame.dispose();
    }
    public static void main(String args[])
    {
        GPACalculator cal = new GPACalculator();
        cal.createUI();
    }
}