NullEnumeration.java

/*
 * Copyright 2004-2012 the Seasar Foundation and the Others.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.seasar.mayaa.impl.util.collection;

import java.util.Enumeration;
import java.util.NoSuchElementException;

/**
 * @author Masataka Kurihara (Gluegent, Inc)
 */
public class NullEnumeration implements Enumeration {

    private static final NullEnumeration NULL_ENUMERATION = new NullEnumeration();

    public static final NullEnumeration getInstance() {
        return NULL_ENUMERATION;
    }

    private NullEnumeration() {
        // singleton.
    }

    public boolean hasMoreElements() {
        return false;
    }

    public Object nextElement() {
        throw new NoSuchElementException();
    }

}