01: /*
02: * Licensed to the Apache Software Foundation (ASF) under one or more
03: * contributor license agreements. See the NOTICE file distributed with
04: * this work for additional information regarding copyright ownership.
05: * The ASF licenses this file to You under the Apache License, Version 2.0
06: * (the "License"); you may not use this file except in compliance with
07: * the License. You may obtain a copy of the License at
08: *
09: * http://www.apache.org/licenses/LICENSE-2.0
10: *
11: * Unless required by applicable law or agreed to in writing, software
12: * distributed under the License is distributed on an "AS IS" BASIS,
13: * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14: * See the License for the specific language governing permissions and
15: * limitations under the License.
16: */
17: package org.apache.harmony.misc;
18:
19: import java.util.Enumeration;
20: import java.util.NoSuchElementException;
21:
22: /**
23: * @author Evgueni Brevnov, Roman S. Bushmanov
24: * @version $Revision: 1.1.6.4 $
25: */
26: public class EmptyEnum<T> implements Enumeration<T> {
27:
28: private static EmptyEnum emptyEnum;
29:
30: private EmptyEnum() {
31: }
32:
33: @SuppressWarnings("unchecked")
34: public static <U> Enumeration<U> getInstance() {
35: if (emptyEnum == null) {
36: emptyEnum = new EmptyEnum();
37: }
38: return emptyEnum;
39: }
40:
41: public boolean hasMoreElements() {
42: return false;
43: }
44:
45: public T nextElement() throws NoSuchElementException {
46: throw new NoSuchElementException();
47: }
48: }
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