作业分为五个部分，分别对应Object Oriented Concepts中的五个知识点进行编程考察。
PART1: CLASS DESIGN
Create a USMoney class with two integer instance variables dollars and cents.
Add a constructor with two parameters for initializing a USMoney object. The
constructor should check that the cents value is between 0 and 99 and, if not,
transfer some of the cents to the dollars variable to make it between 0 and
99. Add a plus() method to the class that takes a USMoney object as its
parameter. It creates and returns a new USMoney object representing the sum of
the object whose plus() method is being invoked and the parameter. It does
not modify the values of the two existing objects. It should also ensure that
the value of the cents instance variable of the new object is between 0 and
99. For example, if x is a USMoney object with 5 dollars and 80 cents, and if
y is a USMoney object with 1 dollar and 90 cents, then x.plus(y) will return a
new USMoney object with 7 dollars and 70 cents. Also, create a USMoneyDemo
class that tests the USMoney class. Document your code appropriately and
include description on how to demonstrate the uses of the classes.
PART2: INHERITANCE
Create a Person class with private instance variables for the person’s name
and birth date. Add appropriate accessor methods for these variables. Then
create a subclass CollegeGraduate with private instance variables for the
student’s GPA and year of graduation and appropriate accessors for these
variables. Don’t forget to include appropriate constructors for your classes.
Then create a class with a main() method that demonstrates your classes.
Document your code appropriately and include description on how to demonstrate
the uses of the classes.
PART3: IMPLEMENTING AN INTERFACE
Create a new class Constants that implements the Series interface provided
below. Its getNext() method repeatedly returns the last value passed in as
an argument to the setStart() method. Until setStart() is called, it
returns 0. Then create a class with a main() method that demonstrates the
use the interface. Document your code appropriately and include description on
how to demonstrate the uses of the classes.
public interface Series {
int getNext();
void reset();
void setStart(int x);
}
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PART4: GENERIC FUNCTION
Implement a generic method containsNull() that takes an array of type T as
its parameter and returns true if any of the values in the array are null.
Then create a class with a main() method that demonstrates the correct
behavior of this generic method. Document your code appropriately and include
description on how to demonstrate the correct behavior.
PART5: USING COLLECTIONS INTERFACES
Write a program that converts an ArrayList to a HashSet to a PriorityQueue to
an ArrayDeque to a TreeSet using the version of their constructors that takes
a Collection as its argument. Start by creating a small ArrayList of strings
and displaying the list using its toString() method. Then similarly
construct and display the other Collections, using each of them as the
argument to the constructor for the next one. Even though the Collections all
contain the same strings, you are likely to see those strings displayed in
different orders for some of the Collections. Then create a class with a main() method that demonstrates the correct behavior of the program.
Document your code appropriately and include description on how to demonstrate
the correct behavior.
