001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.wicket.request.resource;
018
019import org.apache.wicket.request.Request;
020import org.apache.wicket.request.Response;
021import org.apache.wicket.request.handler.resource.ResourceRequestHandler;
022import org.apache.wicket.request.mapper.parameter.PageParameters;
023import org.apache.wicket.util.io.IClusterable;
024import org.apache.wicket.util.lang.Args;
025
026/**
027 * Resource is an object capable of writing output to response.
028 * 
029 * @author Matej Knopp
030 */
031@FunctionalInterface
032public interface IResource extends IClusterable
033{
034        /**
035         * Attributes that are provided to resource in the {@link IResource#respond(Attributes)} method.
036         * Attributes are set by the {@link ResourceRequestHandler}.
037         * 
038         * @author Matej Knopp
039         */
040        class Attributes
041        {
042                private final Request request;
043                private final Response response;
044                private final PageParameters parameters;
045
046                /**
047                 * Construct.
048                 * 
049                 * @param request
050                 * 
051                 * @param response
052                 * @param parameters
053                 */
054                public Attributes(Request request, Response response, PageParameters parameters)
055                {
056                        Args.notNull(request, "request");
057                        Args.notNull(response, "response");
058
059                        this.request = request;
060                        this.response = response;
061                        this.parameters = parameters;
062                }
063
064                /**
065                 * Construct.
066                 * 
067                 * @param request
068                 * @param response
069                 */
070                public Attributes(Request request, Response response)
071                {
072                        this(request, response, null);
073                }
074
075                /**
076                 * Returns current request.
077                 * 
078                 * @return current request
079                 */
080                public Request getRequest()
081                {
082                        return request;
083                }
084
085                /**
086                 * Returns current response. The resource must write output to the response.
087                 * 
088                 * @return response
089                 */
090                public Response getResponse()
091                {
092                        return response;
093                }
094
095                /**
096                 * Returns additional parameters extracted from the request. If resource is created mounted
097                 * {@link ResourceReference}, this method returns all (indexed and query) parameters after
098                 * the mount path. For non mounted {@link ResourceReference}s this method will only return
099                 * the query parameters. For component specific resources the behavior depends on the
100                 * component.
101                 * 
102                 * @return page parameters or <code>null</code>
103                 */
104                public PageParameters getParameters()
105                {
106                        return parameters;
107                }
108        }
109
110        /**
111         * Renders this resource to response using the provided attributes.
112         * 
113         * @param attributes
114         */
115        void respond(Attributes attributes);
116}