1 /* 2 * $Id: IteratorEnumeration.java 358692 2005-12-23 03:37:26Z niallp $ 3 * $Revision: 358692 $ 4 * $Date: 2005-12-23 03:37:26 +0000 (Fri, 23 Dec 2005) $ 5 * 6 * ==================================================================== 7 * 8 * Copyright 2005 The Apache Software Foundation 9 * 10 * Licensed under the Apache License, Version 2.0 (the "License"); 11 * you may not use this file except in compliance with the License. 12 * You may obtain a copy of the License at 13 * 14 * http://www.apache.org/licenses/LICENSE-2.0 15 * 16 * Unless required by applicable law or agreed to in writing, software 17 * distributed under the License is distributed on an "AS IS" BASIS, 18 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 19 * See the License for the specific language governing permissions and 20 * limitations under the License. 21 * 22 */ 23 24 package org.apache.commons.resources.util; 25 26 import java.util.Enumeration; 27 import java.util.Iterator; 28 29 /** 30 * Two way Adaptor class for java.util.Iterator and java.util.Enumeration. 31 */ 32 public class IteratorEnumeration implements Iterator, Enumeration { 33 34 private Iterator iterator; 35 private Enumeration enumeration; 36 37 // -------------------------- Constructors 38 39 /** 40 * Construct an instance which wraps an Iterator. 41 * 42 * @param iterator The <code>Iterator</code> to wrap. 43 */ 44 public IteratorEnumeration(Iterator iterator) { 45 this.iterator = iterator; 46 } 47 48 /** 49 * Construct an instance which wraps an Enumeration. 50 * 51 * @param enumeration The <code>Enumeration</code> to wrap. 52 */ 53 public IteratorEnumeration(Enumeration enumeration) { 54 this.enumeration = enumeration; 55 } 56 57 // -------------------------- Iterator Methods 58 59 /** 60 * <code>remove()<code> is not supported. 61 * @throws UnsupportedOperationException always. 62 */ 63 public void remove() { 64 throw new UnsupportedOperationException(); 65 } 66 67 /** 68 * Indicates whether the wrapped 69 * <code>Iterator/Enumeration</code> has more elements. 70 * 71 * @return <code>true</code> if the wrapped 72 * <code>Iterator/Enumeration</code> has more elements. 73 */ 74 public boolean hasNext() { 75 if (iterator == null) { 76 return enumeration.hasMoreElements(); 77 } else { 78 return iterator.hasNext(); 79 } 80 } 81 82 /** 83 * Returns the next element in the wrapped 84 * <code>Iterator/Enumeration</code>. 85 * 86 * @return the next element. 87 */ 88 public Object next() { 89 if (iterator == null) { 90 return enumeration.nextElement(); 91 } else { 92 return iterator.next(); 93 } 94 } 95 96 // -------------------------- Enumeration Methods 97 98 /** 99 * Indicates whether the wrapped 100 * <code>Iterator/Enumeration</code> has more elements. 101 * 102 * @return <code>true</code> if the wrapped 103 * <code>Iterator/Enumeration</code> has more elements. 104 */ 105 public boolean hasMoreElements() { 106 return hasNext(); 107 } 108 109 /** 110 * Returns the next element in the wrapped 111 * <code>Iterator/Enumeration</code>. 112 * 113 * @return the next element. 114 */ 115 public Object nextElement() { 116 return next(); 117 } 118 119 }