How does the Java ‘for each’ loop work?


List<String> someList = new ArrayList<String>();
// add "monkey", "donkey", "skeleton key" to someList
for (String item : someList) {

What would the equivalent for loop look like without using the for each syntax?


for (Iterator<String> i = someIterable.iterator(); i.hasNext();) {
    String item =;

Note that if you need to use i.remove(); in your loop, or access the actual iterator in some way, you cannot use the for ( : ) idiom, since the actual iterator is merely inferred.

As was noted by Denis Bueno, this code works for any object that implements the Iterable interface.

Also, if the right-hand side of the for (:) idiom is an array rather than an Iterable object, the internal code uses an int index counter and checks against array.length instead. See the Java Language Specification.

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