Squirrel

Your task for this exercise will be to answer questions about a Java program excerpt that models two different types of Robotic Squirrel. The code consists of three Java classes. File SquirrelManager.java contains the class with the harvest method that creates Robotic Squirrel objects and calls methods on these objects. SquirrelSimplex.java and SquirrelSapiens.java contain the classes that model the two different types of Robotic Squirrel. To start, read each of the class comments to get a feel for what they each do.

Download files: SquirrelManager.java, SquirrelSimplex.java, SquirrelSapiens.java
Areas: Introduction to classes and objects.

SquirrelManager.java

1	/**
2	* SquirrelManager: This class manages two Robotic Squirrels. One is a
3	* cheap Robotic Squirrel and the other is an advanced Robotic Squirrel.
4	*
5	* -- A. Bolintineanu, May 2001 (modelled on a program by A. Hunter)
6	*/
7
8	public class SquirrelManager {
9
10	public void harvest() {

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SquirrelSimplex.java

1	/**
2	* SquirrelSimplex: This class models a basic Robotic Squirrel.
3	*/
4
5	public class SquirrelSimplex {
6
7	// number of hazelnuts currently in reservoir
8	private int numHazelnuts;
9
10	/**

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SquirrelSapiens.java

1	/**
2	* SquirrelSapiens: This class models an advanced Robotic Squirrel.
3	*/
4
5	public class SquirrelSapiens {
6
7	// price of one hazelnut (in Martian cents)
8	private int hazelnutPrice = 0;
9
10	// number of hazelnuts currently in reservoir

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Question 1

Open up the full source of SquirrelSimplex.java. At what line number is the variable numHazelnuts declared?

Question 2

Can methods outside class SquirrelSimplex access numHazelnuts?

Question 3

In SquirrelManager.java, how many objects of type SquirrelSimplex are instantiated?

Question 4

How can we find out how many hazelnuts are currently in chip's reservoir?

Question 5

After chip's initial picking of hazelnuts, but before any are extracted, that is, at line 22 of SquirrelManager.java, how many hazelnuts does chip have?

Question 6

How many hazelnuts does dale have after he was first told to pick hazelnut?

Question 7

On lines 35 and 36 of SquirrelManager, does the output appear on the same line or on different lines?

Question 8

For the statement

System.out.println(chip.getNumHazelnuts());

found at line 36 of SquirrelManager.java, what is the output?

Question 9

Open up SquirrelSapiens.java. In the report method, hazelnutPrice, numHazelnuts, and totalValue are not in quotes. Why not?

Question 10

What is the output to the screen after the harvest method in SquirrelManager.java has executed?