// Copyright 2006, 2007, 2008 The Apache Software Foundation

 //

 // 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 org.apache.tapestry5.internal;

 import org.apache.tapestry5.ComponentResources;

 import org.apache.tapestry5.internal.services.PersistentFieldManager;

 import org.apache.tapestry5.internal.structure.Page;

 import org.apache.tapestry5.runtime.RenderQueue;

 /**

  * An extension of {@link org.apache.tapestry5.ComponentResources} that represents additional methods that are private

  * to the framework and not exposed in any public APIs.

  */

 public interface InternalComponentResources extends ComponentResources, InternalComponentResourcesCommon

 {

     /**

      * Get the current persisted value of the field.

      *

      * @param fieldName the name of the field to access

      * @return the value stored for the field, or null if no value is currently stored

      */

     Object getFieldChange(String fieldName);

     /**

      * Checks to see if there is a value stored for the indicated field.

      */

     boolean hasFieldChange(String fieldName);

     /**

      * Posts a change to a persistent field. If the component is still loading, then this change is ignored. Otherwise,

      * it is propagated, via the {@link Page#persistFieldChange(org.apache.tapestry5.ComponentResources, String, Object)

      * page} to the {@link PersistentFieldManager}.

      */

     void persistFieldChange(String fieldName, Object newValue);

     /**

      * Allows the resources to cleanup any render-time only data.

      */

     void postRenderCleanup();

     /**

      * Invoked to make the receiver queue itself to be rendered.

      */

     void queueRender(RenderQueue queue);

     /**

      * Gets access object for the parameter.

      *

      * @param parameterName

      * @return object used to read and update the parameter

      */

     ParameterAccess getParameterAccess(String parameterName);

 }