(The Course class) Revise the Course class as follows: ■ The array size is fixed in Listing 10.6. Improve it to automatically increase the array size by creating a new larger array and copying the contents of the current array to it. ■ Implement the dropStudent method. ■ Add a new method named clear() that removes all students from the course. Write a test program that creates a course, adds three students, removes one, and displays the students in the course.

Sure, here's the revised Course class:

public class Course {
    private String courseName;
    private String[] students = new String[1];
    private int numberOfStudents;

    public Course(String courseName) {
        this.courseName = courseName;
    }

    public void addStudent(String student) {
        if (numberOfStudents == students.length) {
            // create a new larger array and copy the contents of the current array to it
            String[] newStudents = new String[numberOfStudents * 2];
            System.arraycopy(students, 0, newStudents, 0, numberOfStudents);
            students = newStudents;
        }

        students[numberOfStudents] = student;
        numberOfStudents++;
    }

    public void dropStudent(String student) {
        int index = -1;
        for (int i = 0; i < numberOfStudents; i++) {
            if (students[i].equals(student)) {
                index = i;
                break;
            }
        }

        if (index >= 0) {
            for (int i = index; i < numberOfStudents - 1; i++) {
                students[i] = students[i + 1];
            }
            numberOfStudents--;
        }
    }

    public void clear() {
        students = new String[1];
        numberOfStudents = 0;
    }

    public String[] getStudents() {
        return students;
    }

    public int getNumberOfStudents() {
        return numberOfStudents;
    }

    public String getCourseName() {
        return courseName;
    }
}

And here's a test program that creates a course, adds three students, removes one, and displays the students in the course:

public class TestCourse {
    public static void main(String[] args) {
        Course course = new Course("Java Programming");

        course.addStudent("Alice");
        course.addStudent("Bob");
        course.addStudent("Charlie");

        course.dropStudent("Bob");

        String[] students = course.getStudents();
        for (int i = 0; i < course.getNumberOfStudents(); i++) {
            System.out.println(students[i]);
        }
    }
}

Output:

Alice
Charlie