Revise the course class attached with the assignment (testcourse. java source file), as follows:

a. revise the getstudents() method to return an array whose length is the same as the number of students in the course. (hint: create a new array and copy the students to it.)
b. the array size is fixed in the source code provided. revise the addstudent() method to automatically increase the array size if there is no room to add more students. this is done by creating a new larger array and copying the contents of the current array to it.
c. implement the dropstudent() method.
d. add a new method named clear() that removes all the students from the course.
write a test program that creates a course, adds three students, removes one, and displays the students in the course.