Create a class named Student. A Student has fields for an ID number, number of credit hours earned, and number of points earned. (For ex, many schools compute grade point averages based on a scale of 4, so a three-credit-hour class in which a student earns an A is worth 12 points.) Include methods to assign values to all fields. A Student also has a field for grade point average. Include a method to compute the grade point average field by dividing points by credit hours earned.
prepare methods to display the values in each Student field. Save this class as Student.java.

b. prepare a class named ShowStudent that instantiates a Student object from the class you created and assign values to its fields. Compute the Student grade point average, and then display all the values associated with the Student. Save the application as ShowStudent.java.

c. Create a constructor for the Student class you created. The constructor should initialize each Student's ID number to 9999, his or her points earned to 12, and credit hours to 3 (resulting in a grade point average of 4.0). prepare a program that demonstrates that the constructor works by instantiating an object and displaying the initial values. Save the application as ShowStudent2.java.

it solved 10a in the following manner:

/**Created using Spring Source
* Created by: Kim Henry
* On: May 19, 2013
* At: 11:58:00 PM
* CHAPTER_03
* exercise_10a
* Student.java
*/
package exercise_10a;

public class Student
{

static String studentId = "A00268951";
static int creditHours = 15;
static int pointsEarned = 60;
public static double gpa;

public static void main(String []args)
{
Student.getStudentId();
System.out.println("The students Id is: " + studentId + ".");
Student.getCreditHours();
System.out.println("The student has " + creditHours + " credit hours.");
Student.getPointsEarned();
System.out.println("The student earned " + pointsEarned + " points.");
Student.GPA(creditHours, pointsEarned);
}

public static String getStudentId()
{
return studentId;
}
public static void setStudentId(String studentId)
{
Student.studentId = studentId;
}
public static int getCreditHours()
{
return creditHours;
}
public static void setCreditHours(int creditHours)
{
Student.creditHours = creditHours;
}
public static int getPointsEarned()
{
return pointsEarned;
}
public static void setPointsEarned(int pointsEarned)
{
Student.pointsEarned = pointsEarned;
}
public static void GPA(int creditHours, int pointsEarned)
{
gpa = pointsEarned/creditHours;
System.out.println("The students Grade Point Average is " + gpa + ".");
}
public static double getGpa()
{
return gpa;
}
public static void setGpa(double gpa)
{
Student.gpa = gpa;
}
}