The enhanced for statement has the
form:
EnhancedForStatement:
for ( VariableModifiersopt Type Identifier: Expression) Statement
The Expression must either have type
Iterable
or else it must be of an
array type (§10.1), or a compile-time
error occurs.
The scope of a local variable declared
in the FormalParameter part of an
enhanced for
statement (§14.14) is
the contained Statement
The meaning of the enhanced for
statement is given by translation into
a basic for
statement.
If the type of Expression
is a
subtype of Iterable
, then let I
be
the type of the expression
Expression.iterator()
. The enhanced for
statement is equivalent
to a basic for
statement of the
form:
for (I #i = Expression.iterator(); #i.hasNext(); ) {
VariableModifiersopt Type Identifier = #i.next();
Statement
}
Where #i
is a compiler-generated
identifier that is distinct from any
other identifiers (compiler-generated
or otherwise) that are in scope (§6.3)
at the point where the enhanced for
statement 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. Then the
meaning of the enhanced for statement
is given by the following basic for
statement:
T[] a = Expression
L1: L2: ... Lm:
for (int i = 0
VariableModifiersopt Type Identifier = a[i]
Statement
}
Where a and i are compiler-generated
identifiers that are distinct from any
other identifiers (compiler-generated
or otherwise) that are in scope at the
point where the enhanced for statement
occurs.