in a for-loop, what does the (int i : tall) do, where tall is an array of int [duplicate]

Question

As the header says, I was tipped by some people that if I wanted to print the sum of everything in an array of numbers, I should use the above-mentioned parameter for a for-loop (code will follow if further explanation is needed). But what is the exact definiton of what that does? The :-part I mean. Is it; for every number i in the array tall?

import java.util.*;

class Uke36{
    public static void main(String[]args){

    Scanner input=new Scanner(System.in);
    int[] tall=new int[5];

    for (int i=0; i<=4; i++){
        System.out.println("Vennligst oppgi det " + (i+1) + ". tallet: ");
        tall[i]=input.nextInt();
    }
    int sum = 0;
    for(int i : tall){
        sum+=;
    }
    }
}

Answer 1

This is how for-each loops are represented in Java.

for (int i : tall) {
  sum += i;
}

Read it as: For each integer i in the array called tall ...

Answer 2

It's enhanced loop. It was introduced in Java 5 to simplify looping. You can read it as "For each int in tall" and it's like writing:

for(int i = 0; i < tall.length; i++)
   ...

Although it's simpler, but it's not flexible as the for loop.. It's good when you don't really care about the index of the elements.

More reading.

Answer 3

That enhanced for loop equals to

for (int i=0; i < tall.length; i++) {
    System.out.println("Element: " + tall[i]);
}

The below form

 for(int i : tall){

Is the short hand form the classical for loop.

Note:

But there is a condition to use the above form

Form Language specification

The type of the Expression must be Iterable or an array type (§10.1), or a compile-time error occurs.

Here the docs from oracle

Finally

 int sum = 0;
    for(int i : tall){
        sum+=;  // sum = sum+i
    }

That means adding the all elements in the array.

If it Collection, See how that loop converts :What are for-each expressions in Java translated to?