For loops

[karnbmx]

Hello,

I am currently learning Java. While studying loops, I came across FOR loops. The wording from the official Java website I was learning from was a little ambiguous, so I couldn't completely understand it.

So is there any simpler way to understand Java FOR loops? If so, help would be really appreciated.

 

[Chathurga]

[highlight=java]for (int i = 0; i < 5; i++) {
System.out.println("i equals: " + i);
}[/highlight]

That will print out:

i equals: 0
i equals: 1
i equals: 2
i equals: 3
i equals: 4

If you need more explanation just post what you don't understand.

 

[NoEffex]

To go further in-depth,

[highlight=java]for (int i = 0/*Set a variable, you can use a pre-existing one, or nothing*/; i < 5/*The statement that acts much like a while loop*/; i++/*This is executed after each loop.*/) {
System.out.println("i equals: " + i);
}[/highlight]

So, it would be the equivalent of

[highlight=java]int i = 0;
while(i < 5) {
System.out.println("i equals: " + i);
i++;
}[/highlight]

 

[karnbmx]

Cool! Both explanations clear it up a lot. Thanks!

 

[A_Nub]

Also remember the declaration of int i in a for loop is local to that for loop so technically the equivalent is

{
    int i = 0;
    while(i < 5) {
	    System.out.println("i equals: " + i);
            i++;
    }
}

The extra brackets create a so called "section" where anything declared inside is local to that section only. At least thats how it is in C and C++, I would believe java has this functionality too.

Also mind that the above are extremely simplistic samples, just remember for(declaration; conditional; postop) and then you should be set

 

[lilspanyol]

When I started Java , this helped : YouTube - Java Programming Tutorial - 22 - for Loops