    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.hibernate.web.internal;
    016
    017import org.apache.tapestry5.ValueEncoder;
    018import org.apache.tapestry5.commons.services.PropertyAccess;
    019import org.apache.tapestry5.commons.services.PropertyAdapter;
    020import org.apache.tapestry5.commons.services.TypeCoercer;
    021import org.apache.tapestry5.commons.util.ExceptionUtils;
    022import org.apache.tapestry5.ioc.internal.util.InternalUtils;
    023import org.hibernate.Session;
    024import org.hibernate.mapping.Property;
    025import org.slf4j.Logger;
    026
    027import java.io.Serializable;
    028
    029public final class HibernateEntityValueEncoder<E> implements ValueEncoder<E>
    030{
    031    private final Class<E> entityClass;
    032
    033    private final Session session;
    034
    035    private final TypeCoercer typeCoercer;
    036
    037    private final PropertyAdapter propertyAdapter;
    038
    039    private final Logger logger;
    040
    041    public HibernateEntityValueEncoder(Class<E> entityClass, String identifierPropertyName, Session session,
    042                                       PropertyAccess propertyAccess, TypeCoercer typeCoercer, Logger logger)
    043    {
    044        this.entityClass = entityClass;
    045        this.session = session;
    046        this.typeCoercer = typeCoercer;
    047        this.logger = logger;
    048
    049        propertyAdapter = propertyAccess.getAdapter(this.entityClass).getPropertyAdapter(identifierPropertyName);
    050    }
    051
    052    @Override
    053    public String toClient(E value)
    054    {
    055        if (value == null)
    056            return null;
    057
    058        Object id = propertyAdapter.get(value);
    059
    060        if (id == null)
    061        {
    062            return null;
    063        }
    064
    065        return typeCoercer.coerce(id, String.class);
    066    }
    067
    068    @Override
    069    @SuppressWarnings("unchecked")
    070    public E toValue(String clientValue)
    071    {
    072        if (InternalUtils.isBlank(clientValue))
    073            return null;
    074
    075        Object id = null;
    076
    077        try
    078        {
    079
    080            id = typeCoercer.coerce(clientValue, propertyAdapter.getType());
    081        } catch (Exception ex)
    082        {
    083            throw new RuntimeException(String.format(
    084                    "Exception converting '%s' to instance of %s (id type for entity %s): %s", clientValue,
    085                    propertyAdapter.getType().getName(), entityClass.getName(), ExceptionUtils.toMessage(ex)), ex);
    086        }
    087
    088        Serializable ser = (Serializable) id;
    089
    090        E result = (E) session.get(entityClass, ser);
    091
    092        if (result == null)
    093        {
    094            // We don't identify the entity type in the message because the logger is based on the
    095            // entity type.
    096            logger.error(String.format("Unable to convert client value '%s' into an entity instance.", clientValue));
    097        }
    098
    099        return result;
    100    }
    101
    102}