• to provide practice using Java's inheritance and polymorphism mechanisms to design a class.

Installing DrJava

Part I: Progression 1

Source

Write a Java class that extends the Progression class to produce a progression where each value is the absolute value of the difference between the previous two values. You should include a default constructor that starts with 2 and 200 as the first two values and a parametric constructor that starts with a specified pair of numbers as the first two values.

Suggestions

• You can use the static Math.abs() method to calculate the absolute values.

• Create a separate directory under your cpsc215 directory for this problem. Then change into that directory and download the following source files into that directory:
  • Progression.java
  • ArithProgression.java
  • FibonacciProgression.java
  • Tester.java

• Before defining your own subclass of Progression, compile and run Tester.java to show that it works correctly for the ArithProgression class. To compile all your source code, including Progression.java, Tester.java, and the source file you create, you would simply type.

      javac Tester.java
  

  To run your program, you would simply type:

      java Tester.java
  

• To test your program, you will have to revise the main() program in the Tester.java class.

Part II: Progression 2

Source

Write a Java class that extends the Progression class to produce a progression where each value is the square root of the previous value. (Note that you can no longer represent each value with an integer.) You should include a default constructor that starts with 65,536 as the first value and a parametric constructor that starts with a specified (double) number as a first value.