package aQute.lib.collections;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.concurrent.atomic.AtomicBoolean;
/**
* Simple facade for enumerators so they can be used in for loops.
*
* @param <T>
*/
public class EnumerationIterator<T> implements Iterable<T>, Iterator<T> {
public static <T> EnumerationIterator<T> iterator(Enumeration< ? extends T> e) {
return new EnumerationIterator<T>(e);
}
private final Enumeration< ? extends T> enumerator;
private final AtomicBoolean done = new AtomicBoolean();
public EnumerationIterator(Enumeration< ? extends T> e) {
enumerator = e;
}
public Iterator<T> iterator() {
if (!done.compareAndSet(false, true))
throw new IllegalStateException("Can only be used once");
return this;
}
public boolean hasNext() {
return enumerator.hasMoreElements();
}
public T next() {
return enumerator.nextElement();
}
public void remove() {
throw new UnsupportedOperationException("Does not support removes");
}
}