Assignment #7 - Chapter 8: Inheritance and Interfaces

From chapter 8, do programming exercises 8.1 and 8.6 (page 334) - Also note the extra instructions below.

Filenames should be

• Triangle.java
• Prob8_6.java

Extra Instructions

1. For exercise 8.1, write the source code in a file named Triangle.java. To compile this, you will need to use the GeometricObject class from the chapter 8 examples. Do not hand in the GeometricObject file -- you only need to hand in the Triangle.java file.
2. For exercise 8.6:
   • Put all the source code into the file Prob8_6.java. Note that this file will contain multiple classes.
   • Instead of writing the test program described in the exercise, just use the test program shown below - class Prob8_6 and the main() method that are given here. You need to write the interface and appropriate classes. You do not need to write main(), since I have provided it
   • Note: The toString() method for class Object (the base class version) returns a string consisting of the name of the class, the '@' symbol, and the hash code of the object (in hexadecimal format). Your output for the toString() method of the Object instance may not look exactly like mine.

The Prob8_6 class

public class Prob8_6
{
    public static void main(String[] args)
    {
        Object[] objects = 
            {  new Object(), new Animal(), new Tiger(), new Chicken(), 
               new Elephant(), new Fruit(), new Apple(), 
               new Orange()
            };

        for (int i = 0; i < objects.length; i++)
        {
            showObject(objects[i]);
        }
    }

    public static void showObject(Object object)
    {
        System.out.print(object);
        if (object instanceof Eatable)
        {
            ((Eatable)object).howToEat();
        }
        System.out.println();
    }
}

Sample run of Exercise 8.6

 java.lang.Object@f4a24a
 Animal
 Tiger
 Chicken (pluck then cook)
 Elephant
 Fruit (eat raw)
 Apple (polish)
 Orange (peel)

Compiling

Submitting: