How does a for each loop guard against an empty list?

Question

I read on http://www.leepoint.net/notes-java/flow/loops/foreach.html. the for each equivalent to

for (int i = 0; i < arr.length; i++) { 
     type var = arr[         


        

Answer 1

As @user3810043 alludes to in their answer comments, the enhanced for statement is literally evaluated the same as an equivalent basic for statement:

14.14.2. The enhanced for statement

...

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

...

Otherwise, the Expression necessarily has an array type, T[].

Let L1 ... Lm be the (possibly empty) sequence of labels immediately preceding the enhanced for statement.

The enhanced for statement is equivalent to a basic for statement of the form:

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

#a and #i are automatically generated identifiers that are distinct from any other identifiers (automatically generated or otherwise) that are in scope at the point where the enhanced for statement occurs.

^ Quote from The Java® Language Specification