// Copyright 2006 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.runtime;

 import org.apache.tapestry5.MarkupWriter;

 /**

  * A command used during rendering of a page.

  */

 public interface RenderCommand

 {

     /**

      * Invoked on an object to request that it render itself. This involves a mix of invoking methods on the writer, and

      * queueing up additional commands (often, representing children of the object that was invoked) to perform

      * additional rendering.

      * <p/>

      * In this way, rendering is a tail recursive algorithm, but is not implemented using tail recursion.

      */

     void render(MarkupWriter writer, RenderQueue queue);

 }