JAVA HW

College Class includes :

$3$ variables$/$properties $$

private String name;

$$ private int age;

$$ private String major;

The rules have been established but have not been enforced by the college class. A scholar student's name and major must be non$-$null, the age of the scholar student must be at least $13,$ and the major of the scholar student must be one of the majors listed below:

public static final String$[]$ majors $=\{$

$"$Computer Engineering", "Mechanical Engineering",

$$ "Electrical Engineering", "Biomedical Engineering",

$$ "Chemical Engineering", "Aerospace Engineering",

$$ "Civil Engineering", "Physics", "Mathematics", "Biology",

$"$Chemistry$",$ "Environmental Science", "Robotics Engineering",

$$ "Materials Science", "Nuclear Engineering", "Biochemistry",

$$ "Geology", "Astronomy", "Statistics", "Computer Development"

$\}$

Make sure to pass each exception an $$error message$$ explaining why the exception happened. All of the exception constructors can receive a String as a parameter. Secondly, you should have $2$ methods in the$$College$$class should throw exceptions when they get invalid arguments.

an$$addOnToAge$$method should throw an exception when it has passed a non$-$positive value.

public void addOnToAge$($int newAge$)\{$

$$ this.age $=$ this.age $+$ newAge;

$\}$

an$$majorChange$$method should throw an exception when passed an invalid major $($one that is not in the list above$).$

public void majorChange$($String major$)\{$

$$ this.major $=$ major;

$\}$

Also, make sure to pass each exception an $$error message$$ explaining why the exception happened. All of the exceptions constructors can receive a string as a parameter. Finally, fill out the$$avAge$$method below, that receives $$ an array of scholar students as a parameter and returns, as a double, the average age of those scholar students.$$Watch out for the null Student objects. Your method should use a$$try and catch to avoid the NullPointerException caused by attempting to access the age of a null scholar student. Null scholar students should not count towards the average age.

public static double avAge$($Student$[]$ students$)\{$

return $0\mathrm{.}0$;

$\}$