    001    // Copyright 2006, 2007, 2008, 2009 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
    015    package org.apache.tapestry5.services;
    016
    017    import java.io.File;
    018    import java.net.URL;
    019    import java.util.List;
    020
    021    /**
    022     * An API agnostic version of {@link javax.servlet.ServletContext}, used to bridge the gaps between the Servlet API and
    023     * the Portlet API.
    024     */
    025    public interface Context
    026    {
    027        /**
    028         * Returns a URL to a resource stored within the context. The path should start with a leading slash.
    029         *
    030         * @param path to the resource (with a leading slash)
    031         * @return the URL for the path, or null if the path does not correspond to a file.
    032         */
    033        URL getResource(String path);
    034
    035        /**
    036         * Attempts to find the actual file, on the file system, that would be provided by the servlet container for the
    037         * given path (which must start with a leading slash). This may return null if no such file exists, or if the
    038         * resource in question is packaged inside a WAR.  If packaged inside a WAR, the contents may be accessed via {@link
    039         * #getResource(String)}.
    040         *
    041         * @param path to  the resource (with a leading slash)
    042         * @return the underlying File, or null if no such file
    043         */
    044        File getRealFile(String path);
    045
    046        /**
    047         * Returns an initial parameter value defined by servlet.
    048         */
    049        String getInitParameter(String name);
    050
    051        /**
    052         * Looks for resources within the web application within the supplied path. The list will be recurively expanded, as
    053         * necessary. The path must start with a leading slash, and usually ends with a slash as well.
    054         *
    055         * @param path to search for (should start with a leading slash)
    056         * @return the matches, sorted alphabetically
    057         */
    058        List<String> getResourcePaths(String path);
    059
    060        /**
    061         * Returns an attribute previously stored into the context with the given name.
    062         *
    063         * @param name used to retrieve the attribute
    064         * @return the attribute, or null if not found
    065         */
    066        Object getAttribute(String name);
    067
    068        /**
    069         * Returns the names of all attributes of the context, sorted alphabetically.
    070         */
    071        List<String> getAttributeNames();
    072
    073        /**
    074         * Returns the MIME content type of the specified file, or null if no content type is known. MIME types are built-in
    075         * to servlet containers and may be futher specified via the web application deployment descriptor.
    076         *
    077         * @param file name of file
    078         * @return the presumed MIME content type, or null if not known
    079         * @since 5.1.0.0
    080         */
    081        String getMimeType(String file);
    082    }