// Copyright 2008 Thiago H. de Paula Figueiredo

 //

 // Licensed under the Apache License, Version 2.0 (the "License");

 // you may not use this file except in compliance with the License.

 // You may obtain a copy of the License at

 //

 //     http://www.apache.org/licenses/LICENSE-2.0

 //

 // Unless required by applicable law or agreed to in writing, software

 // distributed under the License is distributed on an "AS IS" BASIS,

 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 // See the License for the specific language governing permissions and

 // limitations under the License.

 package br.com.arsmachina.tapestrycrud.services;

 import org.apache.tapestry5.PrimaryKeyEncoder;

 import org.apache.tapestry5.corelib.components.ActionLink;

 import org.apache.tapestry5.corelib.components.EventLink;

 import org.apache.tapestry5.corelib.components.PageLink;

 import br.com.arsmachina.tapestrycrud.encoder.ActivationContextEncoder;

 /**

  * Service that informs the primary key field type of a given entity class. Implementations

  * are not obliged to provide this service for any entity class

  * 

  * @author Thiago H. de Paula Figueiredo

  */

 public interface PrimaryKeyTypeService {

         /**

          * <p>

          * Returns the {@link Class} instance representing the primary key field type for a given entity

          * class. It must return null if the given class is not supported.

          * </p>

          * <p>

          * The primary key field type of a given class may not be the one used as primary key column

          * in the database. This can be used to provide prettier URLs for {@link ActionLink}s,

          * {@link EventLink}s or {@link PageLink}s (when no {@link ActivationContextEncoder} is 

          * explicitly provided and one is automatically created from a {@link PrimaryKeyEncoder}).  

          * </p>

          * 

          * @param entityClass a {@link Class} instance. It cannot be null.

          * @return a {@link Class} or null.

          */

         @SuppressWarnings("unchecked")

         Class getPrimaryKeyType(Class entityClass);

         /**

          * Returns the name of the property used as primary key in a given class. The same 

          * assumptions made to {@link #getPrimaryKeyType(Class)} applies here.

          * 

          * @param entityClass a {@link Class} instance. It cannot be null.

          * @return a {@link String} or null.

          */

         @SuppressWarnings("unchecked")

         String getPrimaryKeyPropertyName(Class entityClass);

 }