/*
* JBoss, Home of Professional Open Source
* Copyright 2007, JBoss Inc., and individual contributors as indicated
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.metatype.spi.values;
import java.lang.reflect.Type;
import org.jboss.metatype.api.annotations.MetaMapping;
import org.jboss.metatype.api.types.MetaType;
import org.jboss.metatype.api.types.MetaTypeFactory;
import org.jboss.metatype.api.values.MetaValue;
import org.jboss.reflect.spi.ClassInfo;
import org.jboss.reflect.spi.ConstructorInfo;
import org.jboss.reflect.spi.TypeInfo;
import org.jboss.reflect.spi.TypeInfoFactory;
/**
* MetaMapper.
*
* @param <T> the mapped type
* @author <a href="adrian@jboss.com">Adrian Brock</a>
* @version $Revision: 1.1 $
*/
public abstract class MetaMapper<T>
{
/** The metatype factory */
private static final MetaTypeFactory metaTypeFactory = MetaTypeFactory.getInstance();
/**
* Get a metamapper for a type info
*
* @param typeInfo the type info
* @return the metamapper or null if there isn't one
*/
public static final MetaMapper<?> getMetaMapper(TypeInfo typeInfo)
{
if (typeInfo instanceof ClassInfo == false)
return null;
ClassInfo classInfo = (ClassInfo) typeInfo;
MetaMapper<?> mapper = typeInfo.getAttachment(MetaMapper.class);
if (mapper != null)
return mapper;
MetaMapping mapping = classInfo.getUnderlyingAnnotation(MetaMapping.class);
if (mapping == null)
return null;
try
{
TypeInfoFactory factory = classInfo.getTypeInfoFactory();
ClassInfo mapperClass = (ClassInfo) factory.getTypeInfo(mapping.value());
ConstructorInfo constructor = mapperClass.getDeclaredConstructor(null);
mapper = (MetaMapper<?>) constructor.newInstance(null);
typeInfo.setAttachment(MetaMapper.class.getName(), mapper);
return mapper;
}
catch (Error e)
{
throw e;
}
catch (RuntimeException e)
{
throw e;
}
catch (Throwable t)
{
throw new RuntimeException("Error creating MetaMapper " + mapping + " for " + typeInfo.getName());
}
}
/**
* Override this method to map to a specific type
*
* @return the type
*/
public Type mapToType()
{
return null;
}
/**
* Override this method to create your own metatype
*
* @return the metatype
*/
public MetaType getMetaType()
{
Type type = mapToType();
if (type == null)
throw new IllegalStateException("You haven't overridden getMetaType() or mapToType()");
return metaTypeFactory.resolve(type);
}
/**
* Create the meta value
*
* @param metaType the metatype
* @param object the object
* @return the meta value
*/
public abstract MetaValue createMetaValue(MetaType metaType, T object);
/**
* Unwrap the metavalue
*
* @param metaValue the meta value
* @return the object
*/
public abstract T unwrapMetaValue(MetaValue metaValue);
}