    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.
    012package org.apache.tapestry5.services;
    013
    014import org.apache.tapestry5.ioc.internal.util.InternalUtils;
    015
    016/**
    017 * Used to configure the {@link ComponentClassResolver}, to allow it to map library names to library root packages (the
    018 * application namespace is a special case of this). In each case, a prefix on the path is mapped to a package.
    019 *
    020 * The root package name should have a number of sub-packages:
    021 * <dl>
    022 * <dt>pages</dt>
    023 * <dd>contains named pages</dd>
    024 * <dt>components</dt>
    025 * <dd>contains components</dd>
    026 * <dt>mixins</dt>
    027 * <dd>contains component mixins</dd>
    028 * <dt>base</dt>
    029 * <dd>contains base classes</dd>
    030 * </dl>
    031 *
    032 * @see ComponentLibraryInfo
    033 */
    034public final class LibraryMapping
    035{
    036    public final String libraryName, rootPackage;
    037
    038    /**
    039     * Identifies the root package of a library. The application has uses the library name "" (the empty string).
    040     * The special library "core" is all the built-in components.
    041     *
    042     * The library name is sometimes referred to as the "path prefix" or the "virtual folder name". This is for historical
    043     * reasons, as the concept of a library and how it was defined and managed evolved from release to release.
    044     *
    045     * The library name should be alpha numeric, and directly encodable into a URL. It may contain slashes (though this is not
    046     * used often), but may not start or end with one.
    047     *
    048     * Note that it <em>is</em> allowed to contribute multiple LibraryMappings with the library name to the
    049     * {@link ComponentClassResolver}, and the results are merged: the single library will have multiple root packages.
    050     * Be careful that <em>none</em> of the root packages overlap!
    051     *
    052     * @param libraryName
    053     *         the unique identifier for the library.
    054     * @param rootPackage
    055     *         the root package to search for classes; sub-packages will include ".pages", ".components", etc.
    056     */
    057    public LibraryMapping(String libraryName, String rootPackage)
    058    {
    059        assert libraryName != null;
    060        assert InternalUtils.isNonBlank(rootPackage);
    061
    062        if (libraryName.startsWith("/") || libraryName.endsWith("/"))
    063        {
    064            throw new IllegalArgumentException(
    065                    "Library names may not start with or end with a slash.");
    066        }
    067
    068        this.libraryName = libraryName;
    069        this.rootPackage = rootPackage;
    070    }
    071
    072    /**
    073     * Returns the library name; the method is oddly named for historical reasons. The library name is sometimes
    074     * referred to as the virtual folder name.
    075     *
    076     * @deprecated In 5.4, use {@link #libraryName} instead.
    077     */
    078    public String getPathPrefix()
    079    {
    080        return libraryName;
    081    }
    082
    083    public String getRootPackage()
    084    {
    085        return rootPackage;
    086    }
    087
    088    @Override
    089    public String toString()
    090    {
    091        return String.format("LibraryMapping[%s, %s]", libraryName, rootPackage);
    092    }
    093
    094}