[quote=mystic rain;#3646906;1278330503]Well, our professor is a little bit slow in discussing OOP terms and others that's why i'm having an advance study on some parts about OOP (java)[/quote] Wow! you are excited to learn more with regards to programming eh? and not on terms But you know what... terminologies are quite useful too when you will be having interviews that's why I keep on reviewing terms when I will have an interview [quote=mystic rain;#3646906;1278330503][b]import java.util.*;[/b] What is this for? Can you explain what's the purpose of this code for the program? |:[/quote] '*' asterisk means... it will import all the content within the package 'util' so instead of writing: [quote]import java.util.Scanner; import java.util.Arrays;[/quote] you will just write: [quote]import java.util.*;[/quote] [quote=mystic rain;#3646906;1278330503]but still, it has one error :\ I'm just a little bit confuse in using array in java ): I prefer using C program than this one aaaaaargh! hahaha! it's getting on my nerves now |: hmpf![/quote] The error in your code is in this part: [quote]double total=[color=red][b]double[/b][/color] total * numberOfItems;[/quote] And why are you confused in using arrays in java? lol What could be their difference? [quote=mystic rain;#3646906;1278330503]Hey, what is hashmap for? |: and this one also -- itemPrice.put what is .put for? o.o[/quote] The example that I wrote.. is a bit complex and needs more understanding Hashmap is an object much more similar to an array. instead of having indexes... Hashmap uses "key" in which you can access your value. so hashmap always goes with "key-value pair" In your program.. since we have a key "item name" with a corresponding value "item price" For me, Hashmap is the ideal Object to use for this program. and the [b].put[/b] is a method used for Hashmap to add items in it. In this program.. I used a String "key" and a "Double" value, "String" for item Name and "Double" for item price. Hope you got this right hehe [quote=mystic rain;#3646906;1278330503]The Iterator thing is new for me o.o can you explain it also o.o what does it do to the program |:[/quote] Hey! Im not a teacher joke As far as I know Iterator is an object that will traverse the elements being put in a Set or Collection I cannot really elaborate what the Iterator is.. Just Read this article http://leepoint.net/notes-java/data/collections/iterators.html [quote=mystic rain;#3646906;1278330503]that one also -- > the itemprice.containskey o.o what is .containskey for? o.o[/quote] [b]containskey[/b] is a method for Hashmap... in which it will accept a parameter "key" and will return true or false if the hashmap really cointains that key. like what we have in our program. when we added "Jacket" in our Hashmap.. with it's corresponding value 10.00 so when we do itemPrice.containskey("Jacket") this will return true.. coz we added "key" Jacket in our Hashmap. Did you get this right? hehe