001// Copyright 2008-2013 The Apache Software Foundation
002//
003// Licensed under the Apache License, Version 2.0 (the "License");
004// you may not use this file except in compliance with the License.
005// You may obtain a copy of the License at
006//
007// http://www.apache.org/licenses/LICENSE-2.0
008//
009// Unless required by applicable law or agreed to in writing, software
010// distributed under the License is distributed on an "AS IS" BASIS,
011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012// See the License for the specific language governing permissions and
013// limitations under the License.
014
015package org.apache.tapestry5.internal.hibernate;
016
017import org.apache.tapestry5.ValueEncoder;
018import org.apache.tapestry5.ioc.internal.util.InternalUtils;
019import org.apache.tapestry5.ioc.services.PropertyAccess;
020import org.apache.tapestry5.ioc.services.PropertyAdapter;
021import org.apache.tapestry5.ioc.services.TypeCoercer;
022import org.apache.tapestry5.ioc.util.ExceptionUtils;
023import org.hibernate.Session;
024import org.hibernate.mapping.PersistentClass;
025import org.hibernate.mapping.Property;
026import org.slf4j.Logger;
027
028import java.io.Serializable;
029
030public final class HibernateEntityValueEncoder<E> implements ValueEncoder<E>
031{
032    private final Class<E> entityClass;
033
034    private final Session session;
035
036    private final TypeCoercer typeCoercer;
037
038    private final PropertyAdapter propertyAdapter;
039
040    private final Logger logger;
041
042    public HibernateEntityValueEncoder(Class<E> entityClass, PersistentClass persistentClass, Session session,
043                                       PropertyAccess propertyAccess, TypeCoercer typeCoercer, Logger logger)
044    {
045        this.entityClass = entityClass;
046        this.session = session;
047        this.typeCoercer = typeCoercer;
048        this.logger = logger;
049
050        Property property = persistentClass.getIdentifierProperty();
051
052        propertyAdapter = propertyAccess.getAdapter(this.entityClass).getPropertyAdapter(property.getName());
053    }
054
055    @Override
056    public String toClient(E value)
057    {
058        if (value == null)
059            return null;
060
061        Object id = propertyAdapter.get(value);
062
063        if (id == null)
064        {
065            return null;
066        }
067
068        return typeCoercer.coerce(id, String.class);
069    }
070
071    @Override
072    @SuppressWarnings("unchecked")
073    public E toValue(String clientValue)
074    {
075        if (InternalUtils.isBlank(clientValue))
076            return null;
077
078        Object id = null;
079
080        try
081        {
082
083            id = typeCoercer.coerce(clientValue, propertyAdapter.getType());
084        } catch (Exception ex)
085        {
086            throw new RuntimeException(String.format(
087                    "Exception converting '%s' to instance of %s (id type for entity %s): %s", clientValue,
088                    propertyAdapter.getType().getName(), entityClass.getName(), ExceptionUtils.toMessage(ex)), ex);
089        }
090
091        Serializable ser = (Serializable) id;
092
093        E result = (E) session.get(entityClass, ser);
094
095        if (result == null)
096        {
097            // We don't identify the entity type in the message because the logger is based on the
098            // entity type.
099            logger.error(String.format("Unable to convert client value '%s' into an entity instance.", clientValue));
100        }
101
102        return result;
103    }
104
105}