Does Java's for-each call an embedded method (that returns the collection) for every iteration?

Question

If there is a method call MyClass.returnArray() and I iterate over the array using the for-each construct (also called the \"enhanced for\" loop):

f         


        

Answer 1

From the java language spec:

EnhancedForStatement:
    for ( VariableModifiersopt Type Identifier: Expression) Statement

and later on:

T[] a = Expression;
L1: L2: ... Lm:
for (int i = 0; i < a.length; i++) {
        VariableModifiersopt Type Identifier = a[i];
        Statement
}

This is (in pseudo code) the equivalent of the advanced for loop for arrays. And it is made clear, that the Expression is evaluated once and the resulting array is assigned to T[] a.

So it's perfectly safe to use even complex expressions in the advanced for loop statement.