001/*
002 *  Copyright 2012 Chris Pheby
003 *
004 *  Licensed under the Apache License, Version 2.0 (the "License");
005 *  you may not use this file except in compliance with the License.
006 *  You may obtain a copy of the License at
007 *
008 *      http://www.apache.org/licenses/LICENSE-2.0
009 *
010 *  Unless required by applicable law or agreed to in writing, software
011 *  distributed under the License is distributed on an "AS IS" BASIS,
012 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 *  See the License for the specific language governing permissions and
014 *  limitations under the License.
015 */
016package org.jadira.scanner.core.utils.lang;
017
018import java.util.Enumeration;
019import java.util.Iterator;
020
021/**
022 * Helper used for working with the JDKs classloader API
023 * @param <E> Subject of the enumeration to be wrapped
024 */
025public class IterableEnumeration<E> implements Iterable<E> {
026
027    private final Enumeration<E> enumeration;
028
029    /**
030     * Creates a new instance
031     * @param enumeration The enumeration to be wrapped
032     */
033    public IterableEnumeration(Enumeration<E> enumeration) {
034        this.enumeration = enumeration;
035    }
036
037    /**
038     * Returns an iterator wrapping the underlying enumeration
039     */
040    public Iterator<E> iterator() {
041
042        return new Iterator<E>() {
043
044            public boolean hasNext() {
045                return enumeration.hasMoreElements();
046            }
047
048            public E next() {
049                return enumeration.nextElement();
050            }
051
052            public void remove() {
053                throw new UnsupportedOperationException("IterableEnumeration does not support remove");
054            }
055        };
056    }
057
058    /**
059     * Typesafe factory method for construction convenience
060     * @param enumeration The enumeration to be wrapped
061     * @param <E> Type-arg for the relevant enumeration
062     * @return An Iterable instance for subject type, E
063     */
064    public static <E> Iterable<E> wrapEnumeration(Enumeration<E> enumeration) {
065        return new IterableEnumeration<E>(enumeration);
066    }
067}