src/main/java/de/uapcore/lightpit/ModuleManager.java

changeset 79
f64255a88d66
parent 78
bb4c52bf3439
child 80
27a25f32048e
--- a/src/main/java/de/uapcore/lightpit/ModuleManager.java	Sat May 23 13:52:04 2020 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,172 +0,0 @@
-/*
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
- *
- * Copyright 2018 Mike Becker. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- *   1. Redistributions of source code must retain the above copyright
- *      notice, this list of conditions and the following disclaimer.
- *
- *   2. Redistributions in binary form must reproduce the above copyright
- *      notice, this list of conditions and the following disclaimer in the
- *      documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
- * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- */
-package de.uapcore.lightpit;
-
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import javax.servlet.Registration;
-import javax.servlet.ServletContext;
-import javax.servlet.ServletContextEvent;
-import javax.servlet.ServletContextListener;
-import javax.servlet.annotation.WebListener;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.List;
-import java.util.Optional;
-
-/**
- * Scans registered servlets for LightPIT modules.
- */
-@WebListener
-public final class ModuleManager implements ServletContextListener {
-
-    private static final Logger LOG = LoggerFactory.getLogger(ModuleManager.class);
-
-    /**
-     * The attribute name in the servlet context under which an instance of this class can be found.
-     */
-    public static final String SC_ATTR_NAME = ModuleManager.class.getName();
-    private ServletContext sc;
-
-    /**
-     * Maps class names to module information.
-     */
-    private final List<LightPITModule> registeredModules = new ArrayList<>();
-
-    /**
-     * Contains the menu entries for the loaded modules.
-     */
-    private final List<MenuEntry> mainMenu = new ArrayList<>();
-
-    @Override
-    public void contextInitialized(ServletContextEvent sce) {
-        sc = sce.getServletContext();
-        reloadAll();
-        sc.setAttribute(SC_ATTR_NAME, this);
-        LOG.info("Module manager injected into ServletContext.");
-    }
-
-    @Override
-    public void contextDestroyed(ServletContextEvent sce) {
-        unloadAll();
-    }
-
-    private Optional<LightPITModule> getModuleInfo(Registration reg) {
-        try {
-            final Class<?> scclass = Class.forName(reg.getClassName());
-
-            final boolean lpservlet = AbstractLightPITServlet.class.isAssignableFrom(scclass);
-            final boolean lpmodule = scclass.isAnnotationPresent(LightPITModule.class);
-
-            if (lpservlet && !lpmodule) {
-                LOG.warn(
-                        "{} is a LightPIT Servlet but is missing the module annotation.",
-                        reg.getClassName()
-                );
-            } else if (!lpservlet && lpmodule) {
-                LOG.warn(
-                        "{} is annotated as a LightPIT Module but does not extend {}.",
-                        reg.getClassName(),
-                        AbstractLightPITServlet.class.getSimpleName()
-                );
-            }
-
-            if (lpservlet && lpmodule) {
-                final LightPITModule moduleInfo = scclass.getAnnotation(LightPITModule.class);
-                return Optional.of(moduleInfo);
-            } else {
-                return Optional.empty();
-            }
-        } catch (ClassNotFoundException ex) {
-            LOG.error(
-                    "Servlet registration refers to class {} which cannot be found by the class loader (Reason: {})",
-                    reg.getClassName(),
-                    ex.getMessage()
-            );
-            return Optional.empty();
-        }
-    }
-
-    private void handleServletRegistration(String name, Registration reg) {
-        final Optional<LightPITModule> moduleInfo = getModuleInfo(reg);
-        if (moduleInfo.isPresent()) {
-            registeredModules.add(moduleInfo.get());
-            LOG.info("Module detected: {}", name);
-        } else {
-            LOG.debug("Servlet {} is no module, skipping.", name);
-        }
-    }
-
-    /**
-     * Scans for modules and reloads them all.
-     */
-    public void reloadAll() {
-        registeredModules.clear();
-        sc.getServletRegistrations().forEach(this::handleServletRegistration);
-        createMainMenu();
-
-        LOG.info("Modules loaded.");
-    }
-
-    /**
-     * Unloads all found modules.
-     */
-    public void unloadAll() {
-        registeredModules.clear();
-        LOG.info("All modules unloaded.");
-    }
-
-    /**
-     * Populates the main menu based on the registered modules.
-     */
-    private void createMainMenu() {
-        mainMenu.clear();
-        registeredModules
-                .stream()
-                .filter(mod -> !mod.systemModule())
-                .map(mod -> new MenuEntry(
-                        new ResourceKey(
-                                mod.bundleBaseName(),
-                                "menuLabel"),
-                        mod.modulePath() + "/",
-                        mod.defaultPriority()))
-                .sorted()
-                .forEachOrdered(mainMenu::add);
-    }
-
-    /**
-     * Returns the main menu.
-     *
-     * @return a list of menu items
-     */
-    public List<MenuEntry> getMainMenu() {
-        return Collections.unmodifiableList(mainMenu);
-    }
-}

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