IteratorWrapper

IteratorWrapper.java

package com.example;
import java.util.Iterator;

/**
 *
 * Usage:
 *   You have a method that returns an iterator (I'm looking at you org.apache.commons.io.FileUtils.lineIterator !!!)
 *   but you want to use the snazzy for-syntax. Look no further:
 * 
 *   import static IteratorWrapper.iterable;
 *   ...
 *   for( String line: iterable(iterator) ) {
 *       System.out.println(line)
 *   }
 */
public class IteratorWrapper {
    public static <E> Iterable<E> iterable(final Iterator<E> iterator) {
        return new Iterable<E>() {
            boolean hasBeenUsed = false;
            public Iterator<E> iterator() {
                if( hasBeenUsed ) {
                    throw new RuntimeException("You can't use this twice, numbnut!");
                } else {
                    hasBeenUsed = true;
                    return iterator; 
                }
            }
        };
    }
}