001    /**
002     *   GRANITE DATA SERVICES
003     *   Copyright (C) 2006-2013 GRANITE DATA SERVICES S.A.S.
004     *
005     *   This file is part of the Granite Data Services Platform.
006     *
007     *   Granite Data Services is free software; you can redistribute it and/or
008     *   modify it under the terms of the GNU Lesser General Public
009     *   License as published by the Free Software Foundation; either
010     *   version 2.1 of the License, or (at your option) any later version.
011     *
012     *   Granite Data Services is distributed in the hope that it will be useful,
013     *   but WITHOUT ANY WARRANTY; without even the implied warranty of
014     *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
015     *   General Public License for more details.
016     *
017     *   You should have received a copy of the GNU Lesser General Public
018     *   License along with this library; if not, write to the Free Software
019     *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
020     *   USA, or see <http://www.gnu.org/licenses/>.
021     */
022    package org.granite.seam21;
023    
024    import java.lang.reflect.Type;
025    
026    import org.granite.messaging.amf.io.convert.Converter;
027    import org.granite.messaging.amf.io.convert.Converters;
028    import org.granite.messaging.amf.io.convert.Reverter;
029    import org.granite.util.TypeUtil;
030    import org.jboss.seam.core.Expressions;
031    import org.jboss.seam.core.Expressions.ValueExpression;
032    
033    /**
034     * @author William DRAI
035     */
036    public class ValueExpressionConverter extends Converter implements Reverter {
037        
038        private Expressions expressions = new Expressions();
039    
040        public ValueExpressionConverter(Converters converters) {
041            super(converters);
042        }
043    
044        @Override
045        protected boolean internalCanConvert(Object value, Type targetType) {
046            Class<?> targetClass = TypeUtil.classOfType(targetType);
047            return (
048                targetClass != Object.class && targetClass.isAssignableFrom(ValueExpression.class) &&
049                (value instanceof String || value == null)
050            );
051        }
052    
053        @Override
054        protected Object internalConvert(Object value, Type targetType) {
055            if (value == null)
056                return null;
057            return expressions.createValueExpression((String)value);
058        }
059    
060        public boolean canRevert(Object value) {
061            return value instanceof ValueExpression<?>;
062        }
063    
064        public Object revert(Object value) {
065            return ((ValueExpression<?>)value).getExpressionString();
066        }
067    
068    }