001    package org.apache.ojb.broker.accesslayer.conversions;
002    
003    /* Copyright 2002-2005 The Apache Software Foundation
004     *
005     * Licensed under the Apache License, Version 2.0 (the "License");
006     * you may not use this file except in compliance with the License.
007     * You may obtain a copy of the License at
008     *
009     *     http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    
018    /**
019     * this implementation of the FieldConversion interface converts 
020     * int to Integer, Integer to int. If the int is zero, then
021     * we don't have a value for the key and it must be set to null, not
022     * zero.
023     * @author Aaron Oathout
024     * @version $Id: Int2IntegerFieldConversion.java,v 1.1 2007-08-24 22:17:31 ewestfal Exp $
025     */
026    public class Int2IntegerFieldConversion implements FieldConversion
027    {
028    
029        private static final Integer NULL_INTEGER = null;
030        private static final Integer ZERO = new Integer(0);
031    
032        public Object javaToSql(Object obj) throws ConversionException
033        {
034            if (obj instanceof Integer)
035            {
036                Integer instance = (Integer) obj;
037                if (instance.equals(ZERO))
038                {
039                    return NULL_INTEGER;
040                }
041                else
042                {
043                    return obj;
044                }
045            }
046            else
047            {
048                return obj;
049            }
050        }
051    
052        public Object sqlToJava(Object obj) throws ConversionException
053        {
054            return obj;
055        }
056    }