Jerry Carpenter

Great after much headaches for me and probably you guys. I have finally got it all working. I appreciate all the advice, it really helped. This program relied heavily on objects which I was not that familiar with. But after over looking how this thing really works; I am really beginning to understand it.
thanks fellas.

How exactly would I go about giving a class references to the other.
code:
/* * * */ package schedule; import java.io.*; import java.util.*; import javax.swing.*; /** * * @author */ public class schedule extends JFrame { ArrayList<Course> courses = new ArrayList<Course>(); ArrayList<Student> students = new ArrayList<Student>(); schedule() throws IOException { Scanner courseFile = new Scanner(new File("C:\\CS1337Asg4Class.txt")); while (courseFile.hasNext()) { String line = courseFile.nextLine(); StringTokenizer st = new StringTokenizer(line, ","); String courseCode = st.nextToken(); String courseName = st.nextToken(); String courseTime = st.nextToken(); Course course = new Course(courseCode,courseName,courseTime); courses.add(course); } Scanner studentFile = new Scanner(new File("C:\\CS1337Asg4Student.txt")); while (studentFile.hasNext()) { String line = studentFile.nextLine(); StringTokenizer st = new StringTokenizer(line, ","); String id = st.nextToken(); String lastName = st.nextToken(); String firstName = st.nextToken(); Student student = new Student(id, lastName, firstName); students.add(student); while (st.hasMoreTokens()) { String courseId = st.nextToken(); Course course = findCourse(courseId); course.students.add(student); student.courses.add(course); } } } Course findCourse(String id) { for (Iterator i = courses.iterator(); i.hasNext(); ) { Course course = (Course)i.next(); if (course.courseCode.equals(id)) { return course; } } return null; } class Student { String id; String lastName; String firstName; ArrayList courses = new ArrayList(); Student(String id, String lastName, String firstName) { this.id = id; this.lastName = lastName; this.firstName = firstName; } } class Course { String courseCode; String courseName; String courseTime; ArrayList students = new ArrayList(); Course(String courseCode, String courseName, String courseTime) { this.courseCode = courseCode; this.courseName = courseName; this.courseTime = courseTime; } } /** * @param args the command line arguments */ public static void main(String[] args)throws IOException { // TODO code application logic here new schedule(); } } [edit]Disable smilies. CR[/edit]
[ November 11, 2008: Message edited by: Campbell Ritchie ]

well my code above shows the layout of the program. and it does return a value
and it is an object.

Well it reads the courseId from the student and sends it to the findCourse method which iterates through the courses and if it finds a match it returns the course. Now evidently I am supposed to make a link between the two and thats where I am just flat out lost.

Well I still dont understand what is meant by adding the student to the course "<link course to student>;". And how I would be able to represent that in a gui interface. Im sure you fella's are getting tired of my questions by now LOL

so would I say course.equal(courseId)

I did a little more and I created another arraylist named sc
if(course.equals(course.courseCode)) { sc.add(student); }
is this the general idea or not?

Im still not sure what is meant by placing the student in the list of the course. How would I do that.
Here is what I got for that code
while (st.hasMoreTokens()) { String courseId = st.nextToken(); Course course = findCourse(courseId); if(course.equals(course.courseCode)) { } } }

then if it does indeed match I would place that student with the course. I just dont understand how to make it happen. I dont even know if this code is how you get it done. Also, how is this going to work in the gui.

Im not sure how to create the link, and how it would work. This will work in a gui interface right?

Ok cool now this part gave me an error (course.id.equals(id)) so I changed it to (course.courseCode.equals(id)) should i have left that alone. Also, can I store the ArrayList students in a JList and the ArrayList courses in a JList as well.

Well all I need it to do is when I click on a student it show his courses. And when clicking on a course it show the students in that specific course. So, I dont need it to add or drop courses. Can this be done with the way its set up. Obviously, Im going to have two separate JList's.

Here is my new code put together; I dont know if its right or not.
/* * * */ package schedule; import java.io.*; import java.util.Scanner; import java.util.StringTokenizer; import java.util.ArrayList; import java.util.Iterator; /** * * @author */ public class schedule { ArrayList<Course> courses = new ArrayList<Course>(); ArrayList<Student> students = new ArrayList<Student>(); schedule() throws IOException { Scanner courseFile = new Scanner(new File("C:\\CS1337Asg4Class.txt")); while (courseFile.hasNext()) { String line = courseFile.nextLine(); StringTokenizer st = new StringTokenizer(line, ","); String courseCode = st.nextToken(); String courseName = st.nextToken(); String courseTime = st.nextToken(); Course course = new Course(courseCode,courseName,courseTime); courses.add(course); } Scanner studentFile = new Scanner(new File("C:\\CS1337Asg4Student.txt")); while (studentFile.hasNext()) { String line = studentFile.nextLine(); StringTokenizer st = new StringTokenizer(line, ","); String id = st.nextToken(); String lastName = st.nextToken(); String firstName = st.nextToken(); Student student = new Student(id, lastName, firstName); students.add(student); while (st.hasMoreTokens()) { String courseId = st.nextToken(); Course course = findCourse(courseId); } } } class Student { String id; String lastName; String firstName; Student(String id, String lastName, String firstName) { this.id = id; this.lastName = lastName; this.firstName = firstName; } } Course findCourse(String id) { for (Iterator i = courses.iterator(); i.hasNext() :wink: { Course course = (Course)i.next(); if (course.courseCode.equals(id)) { return course; } } return null; } class Course { String courseCode; String courseName; String courseTime; Course(String courseCode, String courseName, String courseTime) { this.courseCode = courseCode; this.courseName = courseName; this.courseTime = courseTime; } } /** * @param args the command line arguments */ public static void main(String[] args)throws IOException { // TODO code application logic here new schedule(); } }
Now the linking process needs to be for both as in, I click on student and it shows their courses; clicking on the course will show the students in the course. So, my question is do I still only have to do the link only once in the student section?

Im sorry I keep bothering you on this.
But where are you telling me to put this code
Scanner studentFile = new Scanner(new File("C:\\CS1337Asg4Student.txt")); while (studentFile.hasNext()) { String line = studentFile.nextLine(); StringTokenizer st = new StringTokenizer(line, ","); String id = st.nextToken(); String lastName = st.nextToken(); String firstName = st.nextToken(); Student student = new Student(id, lastName, firstName); students.add(student); while (st.hasMoreTokens()) { String courseId = st.nextToken(); Course course = findCourse(courseId); <link course to student>; } }

and then this code:
Course findCourse(String id) { for (Iterator i = courses.iterator(); i.hasNext(); ) { Course course = (Course)i.next(); if (course.id.equals(id)) { return course; } } return null; }
Also I see you have references of students and courses. Should those be ArrayList as well to student and course

wait i think i see what you mean.
ArrayList<Student> students = new ArrayList<Student>();
ArrayList<Course> courses = new ArrayList<Course>();
correct?

so no ArrayList for the student? just for the course? also I see no creation of a Course class do I need one?