Iterator vs Loop

[uthaman]

what is the difference between iterator and lops

[Nepomuk]

what is the difference between iterator and lops

An Iterator is an Object, which goes through a Collection (e.g. Vector, List, ...) and you can do something with whatever the Iterator is pointing at.

A Loop is a construct, that repeats something for a certain amount of times.

Iterators and Loops are often used together. What I guess you mean is: What's the difference between

Vector<String> vector = new Vector<String>();
vector.add("Hello");
vector.add("World");
 
for(int i=0; i<vector.size();i++)
{
    System.out.println(vector.elementAt(i));
}
 

and

Vector<String> vector = new Vector<String>();
vector.add("Hello");
vector.add("World");
 
Iterator vectorIterator = vector.iterator();
while(vectorIterator.hasNext())
{
   System.out.println(vectorIterator.next());
}
 

(You can replace the Vector with another Collection.)

One big advantage of the first option is, that you always know, at which position you are.

One big advantage of the second option is, that you don't have to know the size of your Collection.

I can't think of any further differences in the usage at the moment, but the concept is, as you see, quite different.

Greetings,
Nepomuk

[r035198x]

what is the difference between iterator and lops

If "lops" was supposed to be loop, then
an Iterator is an interface that facilitates enumeration over a collection while a loop is a program construct that facilitates repetition in a program.

P.S Changed thread title