Using Iterator command to iterate through an ArrayList

[Alpa]

Hi folks!

I'm new to Java so I'm suffering noob problems :(. I hope you guys can help me out a bit.

I have created an ArrayList containing several objects. Now I want to benefit from the Iterator command. I want to display the very first object (and delete it right afterwards). But all I was able to do was to display the whole list.

For instance: I have 35 (Integer) objects in my ArrayList. Now I don't want to display the whole list. I just want to select the first object from the list and display it. And after that, I want to delete it immediately so that I only have 34 objects left.

Can someone help me out please?

Greetings, Alpa

[eRaaaa]

get(index) and remove(index) ?? Read the API Doc : List (Java Platform SE 6)

[Alpa]

I did find the get(index) command. But I don't really get how to integrate it into the following code:

[JAVA]
Iterator iterator = VARIABLE.iterator();
while(iterator.hasNext())
System.out.println(iterator.next());
[/JAVA]

[eRaaaa]

You don`t need the iterator if you want only one object ?! the iterator is as the name implies, for iterating :D
call VARIABLE.get(0)

Or for your code:
while(iterator.hasNext()){
System.out.println(iterator.next());break;}

but thats ugly in my opinion :D

[Alpa]

Thanks alot. I don't really get the "get" command so I used the while loop instead which is working perfectly.

I really don't want to bother you but I have another question: How can I combine an if-else statement or a switch-case statement with the displayed object. For instance if I have the number "5" as a result, I want the sentence "This is number FIVE" being printed on the screen. But if I use the following codes:

if(iterator.next() == 5){ System.out.println("This is number FIVE"); } else { System.out.println("This is NOT number FIVE"); }

It's not working. I guess the problem's the condition, iterator.next() == 5. More precisely the iterator.next(). But what do I have to write instead?

[Norm]

if(iterator.next() == 5)

What kind of data does the next() method return? Your code compares what it returns to an int value.
Does that make sense?

Add a println to show what value is returned by the next() method to see if you are getting any with a value of 5

[eRaaaa]

The problem is, that you dont use a generic iterator, so next() will be for the compiler of type object. no matter whats really in it.

		Iterator<Integer> iterator = VARIABLE.iterator();
		while (iterator.hasNext()) {
			if (iterator.next() == 5) { //or better use the equals method: if (iterator.next().equals(5))
				System.out.println("This is number FIVE");
			} else {
				System.out.println("This is NOT number FIVE");
			}
		}

[Alpa]

What kind of data does the next() method return? Your code compares what it returns to an int value.
Does that make sense?

Add a println to show what value is returned by the next() method to see if you are getting any with a value of 5

next() is giving me a random number between 0 and 35. Now I want to check how often I receive number 5 as answer. And if I receive it, I want it to display the mentioned sentence.