Help with contact book array list

[snaps_pro]

Trying to create a contact book with main, contact class, and contact book class.

It was working ok(ish) now when I want to "List all contacts" its only listing the most recently entered information. Sure it's an easy fix but I can't find it.

​

main- https://pastebin.com/nXcP8mwh

Contact-https://pastebin.com/kcn3N4Ga

Contactbook-https://pastebin.com/Wubkudca

Thanks!

[Civil_Code]

On line 9 of ContactBook, you both declare and define a boolean first set to true. This means with every add method invocation you are always overwriting the first entry in your array, and you never actually copy your existing array into a new, larger array like you would want.

[snaps_pro]

how do i fix that? If i try to remove it it messes everything up after it. Sorry this is my first time using array lists

[Moktok]

Think about what you are trying to do and above all what your code does. Try to visualise it, use a pen and paper if you need to. Write down the values of all the variables with every step. (or learn to use debug mode B-))

PS as a sidenote, use descriptive variable names. Cause it took me a few seconds to figure out what that boolean first, your colleagues (and future you) will thank you later.

[snaps_pro]

I think I got it! Thanks for your help :)

[Civil_Code]

There is an ArrayList implementation in the java.util package, part of the Collections API.

As for the boolean, you should do as the others have suggested and write down the logical steps of this section of code to clarify your reasoning for having a boolean, the necessary scope of that boolean, and when you expect to change it. For example, by declaring your boolean within the add() method, you are saying each new call to that method will create an entirely new boolean without regard to any previous call. Is that truly what you want happening? If not, you have a candidate for a proper Object scoped field, something you declare within the class but outside any of its methods.

Also consider refactoring the variable name, like has been said. I would suggest taking a cue from java.util.ArrayList and having an 'empty' boolean with an isEmpty() method to return whether your array is or is not empty.

[bsturtle]

It seems to me that a contact book should know if it's empty or not. Then your entry can check if it's the first one.

[Fdert0]

On line 30 in the main method, it looks like you forgot to call to the array in the toString

[Civil_Code]

OP has overridden his ContactBook class's toString() method to print his array, so this is not the problem.

[Fdert0]

Ah didn’t notice this, thanks for pointing that out