Treat Enumeration as Iterator

Question

I have a class that implements the Enumeration interface, but Java\'s foreach loop requires the Iterator interface. Is there an <

Answer 1

or in commons-collections EnumerationUtils

import static org.apache.commons.collections.EnumerationUtils.toList

toList(myEnumeration)

Answer 2

You need a so called "Adapter", to adapt the Enumeration to the otherwise incompatible Iterator. Apache commons-collections has EnumerationIterator. The usage is:

Iterator iterator = new EnumerationIterator(enumeration);

Answer 3

There's nothing that is part of the standard library. Unfortunately you'll have to roll your own adapter. There are examples out there of what others have done, for example:

IterableEnumerator

Answer 4

If you just want something to iterate over in a for-each loop (so an Iterable and not only an Iterator), there's always java.util.Collections.list(Enumeration<T> e) (without using any external libraries).

Answer 5

If you can modify the class then you can simply implement Iterator<T> too and add the remove method..

Answer 6

No need to roll your own. Look at Google's Guava library. Specifically

Iterators.forEnumeration()