001// Copyright 2004, 2005 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.tapestry.link;
016
017import org.apache.tapestry.IMarkupWriter;
018import org.apache.tapestry.IRequestCycle;
019import org.apache.tapestry.components.ILinkComponent;
020
021/**
022 *  Used by various instances of {@link org.apache.tapestry.components.ILinkComponent} to
023 *  actually renderer a link.  Implementations of the interface can manipulate
024 *  some of the details of how the link is written.
025 * 
026 *  <p>
027 *  A link rendered may be used in many threads, and must be threadsafe.
028 *
029 *  @author Howard Lewis Ship
030 *  @since 3.0
031 * 
032 **/
033
034public interface ILinkRenderer
035{
036    /**
037     *  Renders the link, taking into account whether the link is
038     *  {@link org.apache.tapestry.components.ILinkComponent#isDisabled() disabled}.
039     *  This is complicated by the fact that the rendering of the body must be done
040     *  within a nested writer, since the Link component will not render its tag
041     *  until after its body renders (to allow for any wrapped components that need
042     *  to write event handlers for the link).
043     * 
044     *  <p>
045     *  The renderer is expected to call back into the link component to handle
046     *  any informal parameters, and to handle events output.
047     * 
048     * 
049     **/
050
051    public void renderLink(IMarkupWriter writer, IRequestCycle cycle, ILinkComponent linkComponent);
052
053}