001// Licensed under the Apache License, Version 2.0 (the "License");
002// you may not use this file except in compliance with the License.
003// You may obtain a copy of the License at
004//
005//     http://www.apache.org/licenses/LICENSE-2.0
006//
007// Unless required by applicable law or agreed to in writing, software
008// distributed under the License is distributed on an "AS IS" BASIS,
009// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
010// See the License for the specific language governing permissions and
011// limitations under the License.
012
013package org.apache.tapestry5;
014
015import javax.servlet.ServletContext;
016
017import org.apache.tapestry5.modules.TapestryModule;
018
019/**
020 * The TapestryFilter is responsible for intercepting all requests into the web application. It
021 * identifies the requests
022 * that are relevant to Tapestry, and lets the servlet container handle the rest. It is also
023 * responsible for
024 * initializing Tapestry.
025 *
026 * The application is primarily configured via context-level init parameters.
027 *
028 * <dl>
029 * <dt>tapestry.app-package</dt>
030 * <dd>The application package (used to search for pages, components, etc.)</dd>
031 * </dl>
032 *
033 * In addition, a JVM system property affects configuration: <code>tapestry.execution-mode</code>
034 * (with default value "production"). This property is a comma-separated list of execution modes.
035 * For each mode, an additional init parameter is checked for:
036 * <code>tapestry.<em>mode</em>-modules</code>; this is a comma-separated list of module class names
037 * to load. In this way, more precise control over the available modules can be obtained which is
038 * often needed during testing.
039 */
040public class TapestryFilter extends org.apache.tapestry5.http.TapestryFilter {
041    
042    public TapestryFilter() {
043        super();
044    }
045
046    /**
047     * Overridden in subclasses to provide additional module classes beyond those normally located. This implementation
048     * returns an empty array.
049     *
050     * @since 5.3
051     */
052    protected Class[] provideExtraModuleClasses(ServletContext context)
053    {
054        return new Class[] { TapestryModule.class };
055    }
056
057}