1.1 --- a/src/main/java/de/uapcore/lightpit/ModuleManager.java Sat May 23 13:52:04 2020 +0200
1.2 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000
1.3 @@ -1,172 +0,0 @@
1.4 -/*
1.5 - * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
1.6 - *
1.7 - * Copyright 2018 Mike Becker. All rights reserved.
1.8 - *
1.9 - * Redistribution and use in source and binary forms, with or without
1.10 - * modification, are permitted provided that the following conditions are met:
1.11 - *
1.12 - * 1. Redistributions of source code must retain the above copyright
1.13 - * notice, this list of conditions and the following disclaimer.
1.14 - *
1.15 - * 2. Redistributions in binary form must reproduce the above copyright
1.16 - * notice, this list of conditions and the following disclaimer in the
1.17 - * documentation and/or other materials provided with the distribution.
1.18 - *
1.19 - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
1.20 - * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1.21 - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
1.22 - * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
1.23 - * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
1.24 - * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
1.25 - * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
1.26 - * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
1.27 - * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
1.28 - * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
1.29 - * POSSIBILITY OF SUCH DAMAGE.
1.30 - *
1.31 - */
1.32 -package de.uapcore.lightpit;
1.33 -
1.34 -import org.slf4j.Logger;
1.35 -import org.slf4j.LoggerFactory;
1.36 -
1.37 -import javax.servlet.Registration;
1.38 -import javax.servlet.ServletContext;
1.39 -import javax.servlet.ServletContextEvent;
1.40 -import javax.servlet.ServletContextListener;
1.41 -import javax.servlet.annotation.WebListener;
1.42 -import java.util.ArrayList;
1.43 -import java.util.Collections;
1.44 -import java.util.List;
1.45 -import java.util.Optional;
1.46 -
1.47 -/**
1.48 - * Scans registered servlets for LightPIT modules.
1.49 - */
1.50 -@WebListener
1.51 -public final class ModuleManager implements ServletContextListener {
1.52 -
1.53 - private static final Logger LOG = LoggerFactory.getLogger(ModuleManager.class);
1.54 -
1.55 - /**
1.56 - * The attribute name in the servlet context under which an instance of this class can be found.
1.57 - */
1.58 - public static final String SC_ATTR_NAME = ModuleManager.class.getName();
1.59 - private ServletContext sc;
1.60 -
1.61 - /**
1.62 - * Maps class names to module information.
1.63 - */
1.64 - private final List<LightPITModule> registeredModules = new ArrayList<>();
1.65 -
1.66 - /**
1.67 - * Contains the menu entries for the loaded modules.
1.68 - */
1.69 - private final List<MenuEntry> mainMenu = new ArrayList<>();
1.70 -
1.71 - @Override
1.72 - public void contextInitialized(ServletContextEvent sce) {
1.73 - sc = sce.getServletContext();
1.74 - reloadAll();
1.75 - sc.setAttribute(SC_ATTR_NAME, this);
1.76 - LOG.info("Module manager injected into ServletContext.");
1.77 - }
1.78 -
1.79 - @Override
1.80 - public void contextDestroyed(ServletContextEvent sce) {
1.81 - unloadAll();
1.82 - }
1.83 -
1.84 - private Optional<LightPITModule> getModuleInfo(Registration reg) {
1.85 - try {
1.86 - final Class<?> scclass = Class.forName(reg.getClassName());
1.87 -
1.88 - final boolean lpservlet = AbstractLightPITServlet.class.isAssignableFrom(scclass);
1.89 - final boolean lpmodule = scclass.isAnnotationPresent(LightPITModule.class);
1.90 -
1.91 - if (lpservlet && !lpmodule) {
1.92 - LOG.warn(
1.93 - "{} is a LightPIT Servlet but is missing the module annotation.",
1.94 - reg.getClassName()
1.95 - );
1.96 - } else if (!lpservlet && lpmodule) {
1.97 - LOG.warn(
1.98 - "{} is annotated as a LightPIT Module but does not extend {}.",
1.99 - reg.getClassName(),
1.100 - AbstractLightPITServlet.class.getSimpleName()
1.101 - );
1.102 - }
1.103 -
1.104 - if (lpservlet && lpmodule) {
1.105 - final LightPITModule moduleInfo = scclass.getAnnotation(LightPITModule.class);
1.106 - return Optional.of(moduleInfo);
1.107 - } else {
1.108 - return Optional.empty();
1.109 - }
1.110 - } catch (ClassNotFoundException ex) {
1.111 - LOG.error(
1.112 - "Servlet registration refers to class {} which cannot be found by the class loader (Reason: {})",
1.113 - reg.getClassName(),
1.114 - ex.getMessage()
1.115 - );
1.116 - return Optional.empty();
1.117 - }
1.118 - }
1.119 -
1.120 - private void handleServletRegistration(String name, Registration reg) {
1.121 - final Optional<LightPITModule> moduleInfo = getModuleInfo(reg);
1.122 - if (moduleInfo.isPresent()) {
1.123 - registeredModules.add(moduleInfo.get());
1.124 - LOG.info("Module detected: {}", name);
1.125 - } else {
1.126 - LOG.debug("Servlet {} is no module, skipping.", name);
1.127 - }
1.128 - }
1.129 -
1.130 - /**
1.131 - * Scans for modules and reloads them all.
1.132 - */
1.133 - public void reloadAll() {
1.134 - registeredModules.clear();
1.135 - sc.getServletRegistrations().forEach(this::handleServletRegistration);
1.136 - createMainMenu();
1.137 -
1.138 - LOG.info("Modules loaded.");
1.139 - }
1.140 -
1.141 - /**
1.142 - * Unloads all found modules.
1.143 - */
1.144 - public void unloadAll() {
1.145 - registeredModules.clear();
1.146 - LOG.info("All modules unloaded.");
1.147 - }
1.148 -
1.149 - /**
1.150 - * Populates the main menu based on the registered modules.
1.151 - */
1.152 - private void createMainMenu() {
1.153 - mainMenu.clear();
1.154 - registeredModules
1.155 - .stream()
1.156 - .filter(mod -> !mod.systemModule())
1.157 - .map(mod -> new MenuEntry(
1.158 - new ResourceKey(
1.159 - mod.bundleBaseName(),
1.160 - "menuLabel"),
1.161 - mod.modulePath() + "/",
1.162 - mod.defaultPriority()))
1.163 - .sorted()
1.164 - .forEachOrdered(mainMenu::add);
1.165 - }
1.166 -
1.167 - /**
1.168 - * Returns the main menu.
1.169 - *
1.170 - * @return a list of menu items
1.171 - */
1.172 - public List<MenuEntry> getMainMenu() {
1.173 - return Collections.unmodifiableList(mainMenu);
1.174 - }
1.175 -}
