JFrames + Returning a Variable... Beginner's Logical Error

Question

Hi,
I'm new to Java and programming in general. I'm trying to do something that seems pretty simple, but I'm making a logical error that is preventing my little program from working.
All I'm trying to do is this... I've created a little JFrame that asks a user for a university's name, address, and the number of students in the university. All of this is within a class called InputWindowSmall. I just want to be able to return those Strings, univName, univAdress, univStudents, to my main program so I can put them into a different class.
I've tried get methods, but that's silly, it doesn't work, it returns null because the program doesn't wait for the user's input.
Does anyone have any suggestions?
Also... I'm a terribly poor Object-Oriented-Thinker... If I'm doing anything that doesn't make sense in an Object-Oriented-Mindset, please point it out! I'd like to try and get better! Thanks!
CODE
InputWindowSmall
package FinalProject;
import javax.swing.JFrame;
import javax.swing.JLabel;
import java.awt.GridLayout;
import javax.swing.JTextField;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.JButton;
/** Class Definition: Input Window - small input window that asks for University name and address*/
public class InputWindowSmall extends JFrame
     private JLabel nameLabel;
     private JLabel addressLabel;
     private JLabel numberStudentsLabel;
     private JLabel whiteSpace;
     private JTextField nameField;
     private JTextField addressField;
     private JTextField numberStudentsField;
     private JButton okButton;
     private String univName;
     private String univAddress;
     private String univStudents;
     /** Constructor with extra parameters     */
     public InputWindowSmall(University univ)
          //Names title bar of window
          super("Welcome!");
          //Sets layout of window
          setLayout(new GridLayout(4,2));
          //Sets text for nameLabel and adds to window
          JLabel nameLabel = new JLabel("    University Name: ");
          add(nameLabel);
          //Sets and adds nameField to window
          nameField = new JTextField(10);
          add(nameField);
          //Sets text for addressLabel and adds to window
          JLabel addressLabel = new JLabel("    University Address: ");
          add(addressLabel);
          //Sets and adds addressField to window
          addressField = new JTextField(10);
          add(addressField);
          //Sets text for numberStudentsLabel and adds to window
          JLabel numberStudentsLabel = new JLabel("    Number of Students: ");
          add(numberStudentsLabel);
          //Sets and adds numberStudentsField to window
          numberStudentsField = new JTextField(10);
          add(numberStudentsField);
          //Sets and adds white space
          JLabel whiteSpace = new JLabel("         ");
          add(whiteSpace);
          //Sets and adds button
          okButton = new JButton("OK");
          add(okButton);
          //create new ButtonHandler for button event handling
          ButtonHandlerSmall handler = new ButtonHandlerSmall();
          okButton.addActionListener(handler);
     }//end InputWindowSmall
     private class ButtonHandlerSmall implements ActionListener
          public void actionPerformed(ActionEvent event)
               String univName = nameField.getText();
               String univAddress = addressField.getText();
               String univStudents = numberStudentsField.getText();
          }//end actionPerformed
     }//end ButtonHandlerSmall
     public String getUniversityName()
          return univName;
     }//end getUniversityName
     public String getUniversityAddress()
          return univAddress;
     public String getUniversityNumberStudents()
          return univStudents;
}//ProjectTest (contains main)
/** Class Definition: ProjectTest - contains main*/
package FinalProject;
import javax.swing.JFrame;
public class ProjectTest {
     public static void main(String args[])
          //Creates a new university
          University univ = new University();
          //Instantiates and sets up the initial small window which asks for university name, address, and # students
          InputWindowSmall inputWindowSmall = new InputWindowSmall(univ);
          inputWindowSmall.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          inputWindowSmall.setSize(350, 120);
          inputWindowSmall.setVisible(true);
          inputWindowSmall.setLocationRelativeTo(null);
          String univN = inputWindowSmall.getUniversityName();
          String univA = inputWindowSmall.getUniversityAddress();
          String univS = inputWindowSmall.getUniversityNumberStudents();
          System.out.println(univN);
          System.out.println(univA);
          System.out.println(univS);
     }//end main
}Edited by: heathercmiller on Apr 28, 2008 5:57 AM
Edited by: heathercmiller on Apr 28, 2008 5:58 AM

Answer 1

Oh! ...Here is a somewhat important detail I forgot to mention...
There's another class called University (I've included it below). The main part of the program instantiates an object of type University, and that object is passed to the InputWindowSmall class. In the end, I want those variables I mentioned above to be placed within the University object I created. ...And I've already passed a University object to InputWindowSmall... I'm just not entirely sure how to assign values to the variables within the University object while in a different class. ...Does that make any sense?
University
package FinalProject;
import java.util.Arrays;
/** Class Definition: University*/
public class University extends ProjectTest implements TuitionGenerate 
     private String universityName;     /** refers to the name of the University     */
     private String address;               /** refers to the address of the University     */
     private Student studentList[];     /** an array of Student objects                    */
     /** Default Constructor */
     University()
          setuniversityName("University_of_Miami");
          setaddress("555_Coral_Gables_St.");               
     /** Constructor with parameters */
     University(String name,String add)
          setuniversityName(name);
          setaddress(add);
     /** Constructor with extra parameters */
     University(String name,String add, Student array[])
          setuniversityName(name);
          setaddress(add);
          setstudentList(array);
     /** method: gets universityName*/
     public String getuniversityName()
          return universityName;
     /** method: gets address*/
     public String getaddress()
          return address;
     /** method: gets studentList*/
     public Student[] getstudentList()
          return studentList;
     /** method: sets universityName*/
     public void setuniversityName(String name)
          universityName=name;
     /** method: sets address*/
     public void setaddress(String add)
          address=add;
     /** method: sets studentList*/
     public void setstudentList(Student array[])
          studentList=new Student[array.length];
          studentList=array;
     /** method: returns a string representation of universityName and address*/
     public String toString()
          String output="University Name: " + universityName + "\nAddress: " + address + "\n\n";
          return output;
     /** method: sorts the array of students alphbetically by last name*/
     public void studentSort()
          String temp[]=new String[studentList.length];
          for(int i=0;i<studentList.length;i++)
               temp=studentList[i].getlastName();
          Arrays.sort(temp);
          Student temp2[]=new Student[studentList.length];
          for(int i=0;i<temp.length;i++)
               for(int j=0;j<studentList.length;j++)
                    if(temp[i].equals(studentList[j].getlastName()))
                         temp2[i]=studentList[j];
                         break;
          studentList=temp2;               
     /** method: prints the list of students*/
     public void printStudentList()
          System.out.println("Students:\n");
          for(int i=0;i<studentList.length;i++)
               System.out.println(studentList[i].toString());
     /** method: prints tuition from interface GenerateTuition*/
     public void printTuition()
          for(int i=0;i<studentList.length;i++)
               System.out.println(studentList[i].toString());
               System.out.println(" Tuition: $" + studentList[i].calTuition() + "0");
     /** method: gets tuition from calTuition method*/
     public double getTuition(Student x)
               return x.calTuition();
Edited by: heathercmiller on Apr 28, 2008 6:07 AM