import java.util.Arrays;
import java.io.Serializable;

/**
Maintains a list of Student objects, and provides machinery
for working with the list.  This has been revised from an earlier
version to maintain Student objects in sorted order, and to
provide a getStudents method, returning an array of Student objects.
Also updateRecordGui has been added.  It is like updateRecord
except that StudentGui has taken the place of StudentMenu.
@author Melvin Fitting
@version April, 2005
*/

public class StudentList implements Serializable
{
   private Student[] students;
   private int count = 0;
   private static final int DEFAULT_SIZE = 100;

   /**
   @param size maximum size of Student list
   */
   public StudentList(int size)
   {
      students = new Student[size];
   }

   /**
   Makes Student list of default size, currently 100.
   */
   public StudentList()
   {
      this(DEFAULT_SIZE);
   }

   /**
   Adds a student to Student list and returns true, unless list
   is full.  If so, false is returned.
   @param first Student first name
   @param last Student last name
   @return true if student added, false otherwise.
   */
   public boolean addStudent(String first, String last)
   {
      if(students.length == count) return false;
      Student s = new Student(first, last);
      students[count] = s;
      count++;
      Arrays.sort(students, 0, count);
      return true;
   }

   /**
   Checks to see if a student is already in the list.
   @param first Student first name
   @param last Student last name
   @return true if student in list, false otherwise
   */
   public boolean inList(String first, String last)
   {
      if (findStudent(first, last) < 0) return false;
      else return true;
   }

   /**
   Displays a StudentGui for updating a Student record,
   provided student is in the list.  No action taken otherwise.
   @param first Student first name
   @param last Student last name
   */
   public void updateRecord(String first, String last)
   {
      int index = findStudent(first, last);
      if (index >= 0)
         {
            StudentGui m = new StudentGui(students[index]);
            m.setVisible(true);
         }
   }

   /**
   Returns a list of Student objects of exactly the right size.
   @return array of Student
   */
   public Student[] getStudents()
   {
      Student[] temp = new Student[count];
      for(int n = 0; n < count; n++)
        temp[n] = students[n];
      return temp;
   }

   private int findStudent(String first, String last)
   {
      for(int n = 0; n < count; n++)
         if(first.equalsIgnoreCase(students[n].getFirst()) &&
            last.equalsIgnoreCase(students[n].getLast())) return n;
      return -1;
   }
}