001    package org.apache.commons.ognl;
002    
003    /*
004     * Licensed to the Apache Software Foundation (ASF) under one
005     * or more contributor license agreements.  See the NOTICE file
006     * distributed with this work for additional information
007     * regarding copyright ownership.  The ASF licenses this file
008     * to you under the Apache License, Version 2.0 (the
009     * "License"); you may not use this file except in compliance
010     * with the License.  You may obtain a copy of the License at
011     *
012     *   http://www.apache.org/licenses/LICENSE-2.0
013     *
014     * Unless required by applicable law or agreed to in writing,
015     * software distributed under the License is distributed on an
016     * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017     * KIND, either express or implied.  See the License for the
018     * specific language governing permissions and limitations
019     * under the License.
020     */
021    
022    import java.util.Enumeration;
023    import java.util.NoSuchElementException;
024    
025    /**
026     * Implementation of ElementsAccessor that returns an iterator over integers from 0 up to the given target.
027     *
028     * @author Luke Blanshard (blanshlu@netscape.net)
029     * @author Drew Davidson (drew@ognl.org)
030     */
031    public class NumberElementsAccessor
032        implements ElementsAccessor, NumericTypes
033    {
034        /**
035         * {@inheritDoc}
036         */
037        public Enumeration<?> getElements( final Object target )
038        {
039            return new Enumeration<Object>()
040            {
041                private int type = OgnlOps.getNumericType( target );
042    
043                private long next = 0;
044    
045                private long finish = OgnlOps.longValue( target );
046    
047                public boolean hasMoreElements()
048                {
049                    return next < finish;
050                }
051    
052                public Object nextElement()
053                {
054                    if ( next >= finish )
055                    {
056                        throw new NoSuchElementException();
057                    }
058                    return OgnlOps.newInteger( type, next++ );
059                }
060            };
061        }
062    }