Passing information to a class that displays a GUI.

[Jonathan Haybok]

I'm trying to make a program that has methods to manipulate student information in one class (student address, grades etc.), creates several Student objects in the driver class and then uses another class to format a GUI where all the information can be well organized and displayed to the user.

I'm totally stuck as to how to create a class that would create the GUI and let me pass parameters to it.

 import java.awt.*;
import javax.swing.*;
public class StudentInfo extends JPanel
{
	public StudentInfo()
	{
		setLayout (new GridLayout (2,3));
	
		setBackground (Color.green);
	
		JLabel info = new JLabel( [b]I have a toString() method in the Student class that displays a formatted String, but I have no idea how to put it here[/b]);
	}
}   

[Eric Daly]

Do you know how to write methods like getString() and stuff like that? Just make a public getString() method in your Student class and then call it from the GUI class when you want to display it.

[Jonathan Haybok]

Here are my other 2 classes. I've never done a getString() method, how would I use it? The very last comment is where I'm having the bulk of my trouble:

   public class Student {
	// --------------------------------
 	// ----- ENTER YOUR CODE HERE -----
	// MODIFY THIS SECTION OF CODE TO USE
	// THE "this" REFERENCE IN
	// STUDENT CONSTRUCTOR (below)
	// --------------------------------
	private String firstName, lastName;
	private Address homeAddress, schoolAddress;
	private Course course;
	private int test1Score, test2Score, test3Score, average;
	
	//declares static count variable that will be used to count students
	private static int studentCount;

	public final int ERROR = -1;

   //-----------------------------------------------------------------
   // Constructor: Sets up this course with the specified data.
   //-----------------------------------------------------------------
	public Student(String firstName, String lastName, Address homeAddress, Address schoolAddress, Course course) {
		this.firstName = firstName;
		this.lastName = lastName;
		this.homeAddress = homeAddress;
		this.schoolAddress = schoolAddress;
		this.course = course;
		// initialize the 3 student test scores to 0
		test1Score = 0;
		test2Score = 0;
		test3Score = 0;
		
		//increases studentCount every time a Student object is created
		studentCount++;
	} // constructor Student

	//-------------------------------------------------
	// Sets the specified test score to 
	// the specified value
	//-------------------------------------------------
	public boolean setTestScore(int testNumber, int score) {
		switch (testNumber) {
			case 1:	
				test1Score = score;
				break;
			case 2:	
				test2Score = score;
				break;
			case 3:	
				test3Score = score;
				break;
			default: 
				return false;	
		}

		return true;

	} // method setTestScore

	//-------------------------------------------------
	//  Returns the value of the specified test score
	//-------------------------------------------------
	public int getTestScore(int testNumber) {
		switch (testNumber) {
			case 1:	
				return test1Score;
			case 2:	
				return test2Score;
			case 3:	
				return test3Score;
			default: 
				return ERROR;
		}

	} // method getTestScore

	// --------------------------------
 	// ----- ENTER YOUR CODE HERE -----
	// METHOD OVERLOADING:
	// CREATE TWO METHODS FOR AVERAGE.
	// ONE ACCEPTS TWO TEST SCORES AND
	// THE OTHER ACCEPTS THREE TEST SCORES
	// AS PARAMETERS. THE METHOD THAT IS
	// CALLED WILL DEPEND ON HOW MANY
	// TEST SCORES ARE AVAILABLE
	// --------------------------------
	public int average(int test1Score, int test2Score)
	{
		average = (test1Score + test2Score) / 2;
		return average;
	} // method average
	
	public int average(int test1Score, int test2Score, int test3Score)
	{
		average = (test1Score + test2Score + test3Score) / 3;
		return average;
	}
	
	//-------------------------------------------------
	// Returns a String representation of this 
	// Student object for display as output.
	//-------------------------------------------------
	public String toString() {
		String result;

		result = firstName + " " + lastName + "\n" + "Home Address:\n" + homeAddress + "\n";
		result += "School Address:\n" + schoolAddress;
		if (test1Score != ERROR) {
			result += "\nTest 1 score: " + test1Score;
			if (test2Score != ERROR) {
				result += "\nTest 2 score: " + test2Score;
				if (test3Score != ERROR) {
					result += "\nTest 3 score: " + test3Score;
				}
			}
			result += "\nAverage of three scores: " + average;
		}

		return result + "\n";

	} // method toString
	
	// --------------------------------
 	// ----- ENTER YOUR CODE HERE -----
	// USE A STATIC VARIABLE TO KEEP 
	// TRACK OF THE TOTAL NUMBER OF 
	// STUDENTS (HINT: SEE PAGE 300 Red
	// PAGE 303 Green)
	// --------------------------------	
	public static int getCount()
	{
		return studentCount;
	}
	
} // class Student 

  public class CourseDriver {
	//
	// Tests the functionality of the Course class
	//
	public static void main(String[] args){
		//-----------------------------------
		// Create the course
		//-----------------------------------
		Course ISJava = new Course("IS 247", "0301", "3");

		//-----------------------------------
		// Create the addresses
		//-----------------------------------
		Address theSchool = new Address("1000 Hilltop Circle", "Baltimore", "MD", 21250);
		// Student addresses		
		Address johnHouse = new Address("Mystreet St.", "Mytown", "Mystate", 73322);
		Address janeHouse = new Address("104 Rockin' It", "The Casbah", "Virginia", 22255);
		Address billHouse = new Address("123 Main Street", "Anytown", "Maryland", 12345);
	   // --------------------------------
   	// ----- ENTER YOUR CODE HERE -----
		// ADD SEVEN NEW STUDENTS ADDRESSES
	   // --------------------------------
	   //		
		Address carlosHouse = new Address("3423 Fauqier Ct.", "Mt. Airy", "Maryland", 21771);
		Address laronHouse = new Address("761 English Muffin Way", "Frederick", "Maryland", 21701);
		Address santanaHouse = new Address("2814", "Ashburn", "Virginia", 21457);
		Address mikeHouse = new Address("1242", "Bethesda", "Maryland", 23141);
		Address chrisHouse = new Address("23412", "Landover", "Maryland", 12341);
		Address caseyHouse = new Address("2815", "Ashburn", "Virginia", 21457);
		Address londonHouse = new Address("34132", "Bowie", "Maryland", 24512);

		//-----------------------------------
		// Create the students
		//-----------------------------------
		Student johnDoe = new Student("John", "Doe", johnHouse, theSchool, ISJava);
		Student janeDoe = new Student("Jane", "Doe", janeHouse, theSchool, ISJava);
		Student billJones = new Student("Billy", "Jones", billHouse, theSchool, ISJava);
		//
	   // --------------------------------
   	// ----- ENTER YOUR CODE HERE -----
		// ADD SEVEN NEW STUDENTS
	   // --------------------------------
	   //			
		Student carlosRogers = new Student("Carlos", "Rogers", carlosHouse, theSchool, ISJava);
		Student laronLandry = new Student("Laron", "Landry", laronHouse, theSchool, ISJava);
		Student santanaMoss = new Student("Santana", "Moss", santanaHouse, theSchool, ISJava);
		Student mikeSellers = new Student("Mike", "Sellers", mikeHouse, theSchool, ISJava);
		Student chrisCooley = new Student("Chris", "Cooley", chrisHouse, theSchool, ISJava);
		Student caseyRabach = new Student("Casey", "Rabach", caseyHouse, theSchool, ISJava);
		Student londonFletcher = new Student("London", "Fletcher", londonHouse, theSchool, ISJava);

		//-----------------------------------
		// Set the test scores for each student
		//-----------------------------------
		johnDoe.setTestScore(1, 80);
		johnDoe.setTestScore(2, 85);
		johnDoe.setTestScore(3, 70);
				
		janeDoe.setTestScore(1, 94);
		janeDoe.setTestScore(2, 89);
		janeDoe.setTestScore(3, 100);

		billJones.setTestScore(1, 100);
		billJones.setTestScore(2, 100);
		billJones.setTestScore(3, 100);
		
		//tests overloaded method
		carlosRogers.setTestScore(1, 82);
		carlosRogers.setTestScore(2, 76);
		
		laronLandry.setTestScore(1, 80);
		laronLandry.setTestScore(2, 75);
		laronLandry.setTestScore(3, 26);
		
		santanaMoss.setTestScore(1, 95);
		santanaMoss.setTestScore(2, 98);
		santanaMoss.setTestScore(3, 80);
		
		mikeSellers.setTestScore(1, 80);
		mikeSellers.setTestScore(2, 84);
		mikeSellers.setTestScore(3, 73);
		
		chrisCooley.setTestScore(1, 85);
		chrisCooley.setTestScore(2, 90);
		chrisCooley.setTestScore(3, 87);
		
		caseyRabach.setTestScore(1, 88);
		caseyRabach.setTestScore(2, 92);
		caseyRabach.setTestScore(3, 94);
		
		londonFletcher.setTestScore(1, 97);
		londonFletcher.setTestScore(2, 95);
		londonFletcher.setTestScore(3, 98);
		
      //
	   // --------------------------------
   	// ----- ENTER YOUR CODE HERE -----
		// CREATE A SEPARATE METHOD FOR GUI
		// Use GUI Layout Manager for display.
		// You may choose any display format
		// that you want, and use any design
		// Your output should include:
		// -- Total number of students
		// -- Every Student and their data
		//    including their Aggregate Data
		//    (see the Student Class for
		//    details)
		// -- The average test score for each
		//    student (note: the average method
		//    should work for either two or three
		//    test scores).	
		// -- Display semesters that the course
		//    is available (HINT: Use enumerated
		//    display as shown on 
		//    page 323 Red /325 Green 	
		// TIP: Use simple output formats such
		// as System.Out until you have the
		// rest of the program working, and
		// then implement the GUI Layout
		// Manager.
  

[Eric Daly]

Ok, then do you know how to do it using System.out.println? It looks like you only have to display the info once, which means you don't really have to do a Swing gui and get data from another class more than once. Do you know how to use a JOptionPane? Here's the API from Sun. Here's how you can use it:

String message = student1info + student2info + yada yada yada; 
JOptionPane.showMessageDialog(frame, message, "window title");

and here's Sun's tutorial on it.

[Jonathan Haybok]

Eric Daly wrote:Ok, then do you know how to do it using System.out.println? It looks like you only have to display the info once, which means you don't really have to do a Swing gui and get data from another class more than once. Do you know how to use a JOptionPane? Here's the API from Sun. Here's how you can use it:

String message = student1info + student2info + yada yada yada; 
JOptionPane.showMessageDialog(frame, message, "window title");

and here's Sun's tutorial on it.

Thanks for your help. I should have mentioned that the project specifically states that I need to use a GUI layout manager.

I'm just now realizing that my average comes out as 0 in every single case. As you can see I needed to overload two methods to get an average, but for some reason it's wrong?

[Eric Daly]

For your averages, it looks you never called any of the average methods in your code, so the default value for average will be zero for each student, until you set an average grade. By the way you set up your average methods to take in either 2 or 3 int values to be averaged, which makes whatever test scores you set earlier pointless. The average method is only working with the values passed in when you call the average method. Maybe you should have just one average method with no parameters, and it can average the test scores that are stored in the Student object. Otherwise your code looks good.
As for Swing, you might want to just make a JFrame and add either JTextFields or JLabels, it really doesn't matter. Check out Sun's Swing Tutorial, especially HelloWorldSwing.java. Maybe just do a bunch of JLabels and add them all to your JFrame.