Array Holding Many Objects

Jun 29, 2014

okay,I created a program that demonstrated an array holding a number of objects, each from different classes.the printout I got for the first program ended up being gibberish. when I made the program a second time, I got the correct result.I've been trying to pinpoint the anomaly but I can't seem to find it. So ill try breaking down what I did?

Goal:The purpose of the program was to have a single Class (we'll call the Class 'Animal') to pass the parameters of a previously made method. This method would, amongst other things, call on an array.Further, I would then make subclasses of the Class Animal, and then use them as well to pass the method parameters, thus demonstrating subclasses can be used in place of the super class.

3 of these classes were made purely to as a "place setter". the Classes called "Cat" and "Dog" respectively were created to be subclasses of the Class Animal (with no other code inside them aside from "extends Animal)the 3rd "place setter" called "ClasstoHoldObjects" was created to be the array class (ClasstoHoldObjects itself has no code in it aside from the class name)these are the ones we want.Animal class (which holds the coding meant to be used).Here is the Animal Class

public class Animal {
private ClasstoHoldObjects[] thelist = new ClasstoHoldObjects[5];
int i = 0;
public void add(ClasstoHoldObjects x){
if(i < thelist.length){

[code]....

the print out was this next, im putting THIS line in the array... june_6.Dog@a0dcd9 (and the same by the Cat object).I recognize june6 as the package name.

finally, I erased extra lines as well as comments and simplified class names to make the code more readable. If you want the original, or some class names are a bit off- I could give you the original with all its comments and longer named classes

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I'll put the code for each class an explain the problem I have.

package polymorphism;
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[Code] ....

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[Code]...

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[code]....

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[Code] ....

So basically here's what needs to be accomplished with this portion of code:

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7.Once the purchase is complete I need to update the array by subtracting the number of copies of that particular book that was purchased.
8.Print the updated array.
9.Display a count of how many books were purchased, and how much money was made from the purchase.

I know that code has a lot of holes in it, but I'm just trying to get everything together and figure out how to do each step.

The part I'm stuck on right now is trying to figure out how to search the array to first see if the ISBN that was entered is in the array, and then to find the number of copies of the book with that ISBN number.

In case it will visualize what this array looks like, here's a print out of the array from a sample run I just did.

ISBN: 1234567, Price: 31.670000, Copies: 0
ISBN: 1234444, Price: 98.500000, Copies: 4
ISBN: 1235555, Price: 27.890000, Copies: 2
ISBN: 1235566, Price: 102.390000, Copies: 6

[Code] ....

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[Code].....

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[Code] ....

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[Code] .....

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[code]...

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[Code] ....

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[code]....

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However, now to the point.

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[Code]...

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[Code] ....

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[Code] ....

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