2008年11月28日 星期五

Lab Java Constructor

Use Display 4.14 to call 4.13 (2nd ed.) or
Display 4.12 to call 4.11 (1st ed.).

After you finish the above, try the following

Date birthday = new Date("Jan",1,2000);
birthday.Date("Feb",1,2000);
birthday.setDate("Feb",1,2000);
birthday=new Date("Mar",1,2000);



Lab Overloading

Do Display 4.11



Lab ADT

Define a Complex class and write an object oriented program to compute (2+3i)+(4+5i) in Java.
The methods should include an access and a mutator.



2008年11月21日 星期五

lab Fraction equality test

Write a program to implement a method that can check whether 2 fractions are equal. You will implement a class called Fraction consisting of a numerator and a denominator. The equality test of 2 fractions should return a boolean value.

Use the following as the tests.

* 1/2, 2/4
* 5/6, 6/7


Hints:
Fraction f1, f2;
f1.equals(f2);




lab Fraction Addition

Write a program to implement a method that can do additions of 2 fractions. You will implement a class called Fraction consisting of a numerator and a denominator. The additions of
2 fractions should be equal to a fraction.
Use 1/2+1/3 as the test.

Hints:
Fraction f1, f2;
f1.add(f2);



Class Definition 3

Do Display 4.7 (3rd, 2nd ed.) or 4.5 (1st ed.). Then use Display 4.8 to call 4.7.

Question
In Display 4.7, if the method setDate has the parameter as setDate(int month, int day, int year), what kind of changes should be made in its body of codes?




2008年11月7日 星期五

lab class definition 2

Study Display 4.4 (2nd ed. and 3rd ed.) or Display 4.2 & Display 4.3 (1st ed.) and then
1. Comment out date.setDate(6, 17, year); by // date.setDate(6, 17, year);
2. At the next line below, add date.readInput();
3. Run the program again. Fix any problems you may encouter along the way.
4. At the last line of your program, add System.out.println(date.month);
and see what happens. Why?



lab counter

Define a class called Counter whose objects count things. An object of this class records a count that is a nonnegative integer. Include methods to set the counter to 0, to increase the count by 1, and to decrease the count by 1. Include an accessor method that returns the current count value and a method that outputs the count to the screen. Write a program to test

counter.reset();
counter.inc();
counter.inc();
counter.dec();
counter.output();



Homework 10-31-2008

Study Display 4.1 and then do Self-Test Exercise 1.