Java tutorial
package org.jtheque.modules.impl; import org.jtheque.core.Core; import org.jtheque.core.Folders; import org.jtheque.core.utils.OSGiUtils; import org.jtheque.errors.ErrorService; import org.jtheque.errors.Errors; import org.jtheque.i18n.I18NResourceFactory; import org.jtheque.i18n.LanguageService; import org.jtheque.modules.Module; import org.jtheque.modules.ModuleException; import org.jtheque.modules.ModuleException.ModuleOperation; import org.jtheque.modules.ModuleState; import org.jtheque.resources.Resource; import org.jtheque.resources.ResourceService; import org.jtheque.utils.StringUtils; import org.jtheque.utils.ThreadUtils; import org.jtheque.utils.annotations.Immutable; import org.jtheque.utils.annotations.NotThreadSafe; import org.jtheque.utils.bean.Version; import org.jtheque.utils.collections.ArrayUtils; import org.jtheque.utils.collections.CollectionUtils; import org.jtheque.utils.io.FileUtils; import org.jtheque.xml.utils.XML; import org.jtheque.xml.utils.XMLException; import org.jtheque.xml.utils.XMLOverReader; import org.osgi.framework.Bundle; import org.osgi.framework.BundleContext; import org.osgi.framework.BundleException; import org.springframework.osgi.context.BundleContextAware; import java.io.File; import java.io.FileFilter; import java.io.IOException; import java.io.InputStream; import java.util.Collection; import java.util.Dictionary; import java.util.List; import java.util.Locale; import java.util.concurrent.Callable; import java.util.concurrent.CompletionService; import java.util.concurrent.ExecutionException; import java.util.concurrent.ExecutorCompletionService; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.jar.JarFile; import java.util.regex.Pattern; import java.util.zip.ZipEntry; /* * Copyright JTheque (Baptiste Wicht) * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /** * A loader for the modules. * * @author Baptiste Wicht */ @NotThreadSafe public final class ModuleLoader implements BundleContextAware { private static final Pattern COMMA_DELIMITER_PATTERN = Pattern.compile(";"); private static final String[] EMPTY_ARRAY = new String[0]; private BundleContext bundleContext; @javax.annotation.Resource private ResourceService resourceService; @javax.annotation.Resource private LanguageService languageService; @javax.annotation.Resource private Core core; private final ModuleServiceImpl moduleService; /** * Construct a new ModuleLoader. * * @param moduleService The module service. */ public ModuleLoader(ModuleServiceImpl moduleService) { super(); this.moduleService = moduleService; } @Override public void setBundleContext(BundleContext bundleContext) { this.bundleContext = bundleContext; } /** * Load the modules. * * @return All the loaded modules. */ public Collection<Module> loadModules() { File[] files = Folders.getModulesFolder().listFiles(new ModuleFilter()); return isLoadingConcurrent() ? loadInParallel(files) : loadSequentially(files); } /** * Indicate if we must make the loading concurrent. * * @return {@code true} if the loading is concurrent otherwise {@code false}. */ private static boolean isLoadingConcurrent() { String property = System.getProperty("jtheque.concurrent.load"); return StringUtils.isNotEmpty(property) && "true".equalsIgnoreCase(property); } /** * Load all the modules from the given files in parallel (using one thread per processor). * * @param files The files to load the modules from. * * @return A Collection containing all the loaded modules. */ @SuppressWarnings({ "ForLoopReplaceableByForEach" }) private Collection<Module> loadInParallel(File[] files) { ExecutorService loadersPool = Executors.newFixedThreadPool(2 * ThreadUtils.processors()); CompletionService<Module> completionService = new ExecutorCompletionService<Module>(loadersPool); for (File file : files) { completionService.submit(new ModuleLoaderTask(file)); } List<Module> modules = CollectionUtils.newList(files.length); try { for (int i = 0; i < files.length; i++) { modules.add(completionService.take().get()); } } catch (InterruptedException e) { Thread.currentThread().interrupt(); throw new RuntimeException(e); } catch (ExecutionException e) { throw new RuntimeException(e); } loadersPool.shutdown(); return modules; } /** * Load all the modules from the given files sequentially. * * @param files The files to load the modules from. * * @return A Collection containing all the loaded modules. */ private Collection<Module> loadSequentially(File[] files) { List<Module> modules = CollectionUtils.newList(files.length); for (File file : files) { try { modules.add(installModule(file)); } catch (ModuleException e) { //Do not rethrow the exception to try to install the others module. OSGiUtils.getService(bundleContext, ErrorService.class).addError(Errors.newError(e)); } } return modules; } /** * Install the module. * * @param file The file to the module to installFromRepository. * * @return The installed module. * * @throws org.jtheque.modules.ModuleException * If an error occurs during module installation. */ public Module installModule(File file) throws ModuleException { Builder builder = new Builder(); ModuleResources resources = null; try { //Read the config file of the module resources = readConfig(file); //Install the bundle Bundle bundle = bundleContext.installBundle("file:" + file.getAbsolutePath()); builder.setBundle(bundle); //Get informations from manifest readManifestInformations(builder, bundle); } catch (BundleException e) { throw new ModuleException("error.module.config", e, ModuleOperation.INSTALL); } catch (IOException e) { throw new ModuleException("error.module.config", ModuleOperation.INSTALL); } Module module = builder.build(); loadI18NResources(module, resources); moduleService.setResources(module, resources); return module; } /** * Read the config of the module. * * @param file The file of the module. * * @return The module resources. * * @throws IOException If an error occurs during Jar File reading. * @throws org.jtheque.modules.ModuleException * If the config cannot be read. */ private ModuleResources readConfig(File file) throws IOException, ModuleException { JarFile jarFile = null; try { jarFile = new JarFile(file); ZipEntry configEntry = jarFile.getEntry("module.xml"); if (configEntry == null) { return new ModuleResources(CollectionUtils.<ImageResource>emptyList(), CollectionUtils.<I18NResource>emptyList(), CollectionUtils.<Resource>emptyList()); } ModuleResources resources = importConfig(jarFile.getInputStream(configEntry)); //Install necessary resources before installing the bundle for (Resource resource : resources.getResources()) { if (resource != null) { resourceService.installResource(resource); } } return resources; } finally { if (jarFile != null) { jarFile.close(); } } } /** * Import the configuration of the module from the module config XML file. * * @param stream The stream to the file. * * @return The ModuleResources of the module. * * @throws org.jtheque.modules.ModuleException * If the config cannot be read properly. */ private ModuleResources importConfig(InputStream stream) throws ModuleException { XMLOverReader reader = XML.newJavaFactory().newOverReader(); try { reader.openStream(stream); return new ModuleResources(importImageResources(reader), importI18NResources(reader), importResources(reader)); } catch (XMLException e) { throw new ModuleException(e, ModuleOperation.LOAD); } finally { FileUtils.close(reader); } } /** * Read the manifest informations of the given module. * * @param container The module. * @param bundle The bundle. */ private static void readManifestInformations(Builder container, Bundle bundle) { @SuppressWarnings("unchecked") //We know that the bundle headers are a String<->String Map Dictionary<String, String> headers = bundle.getHeaders(); container.setId(headers.get("Bundle-SymbolicName")); container.setVersion(Version.get(headers.get("Bundle-Version"))); if (StringUtils.isNotEmpty(headers.get("Module-Core"))) { container.setCoreVersion(Version.get(headers.get("Module-Core"))); } else { container.setCoreVersion(Core.VERSION); } container.setUrl(headers.get("Module-Url")); container.setUpdateUrl(headers.get("Module-UpdateUrl")); container.setMessagesUrl(headers.get("Module-MessagesUrl")); if (StringUtils.isNotEmpty(headers.get("Module-Collection"))) { container.setCollection(Boolean.parseBoolean(headers.get("Module-Collection"))); } if (StringUtils.isNotEmpty(headers.get("Module-Dependencies"))) { container.setDependencies(COMMA_DELIMITER_PATTERN.split(headers.get("Module-Dependencies"))); } else { container.setDependencies(EMPTY_ARRAY); } } /** * Load the i18n resources of the given module. * * @param module The module to load i18n resources for. * @param resources The resources of the module. */ private void loadI18NResources(Module module, ModuleResources resources) { for (I18NResource i18NResource : resources.getI18NResources()) { List<org.jtheque.i18n.I18NResource> i18NResources = CollectionUtils .newList(i18NResource.getResources().size()); for (String resource : i18NResource.getResources()) { if (resource.startsWith("classpath:")) { i18NResources.add(I18NResourceFactory.fromURL(resource.substring(resource.lastIndexOf('/') + 1), module.getBundle().getResource(resource.substring(10)))); } } languageService.registerResource(i18NResource.getName(), i18NResource.getVersion(), i18NResources.toArray(new org.jtheque.i18n.I18NResource[i18NResources.size()])); } } /** * Import the i18n resources. * * @param reader The XML reader. * * @return A List containing all the I18NResource of the module. * * @throws XMLException If an error occurs during XML parsing. */ private static List<I18NResource> importI18NResources(XMLOverReader reader) throws XMLException { List<I18NResource> i18NResources = CollectionUtils.newList(); while (reader.next("/config/i18n/resource")) { List<String> resources = CollectionUtils.newList(5); String name = reader.readString("@name"); Version version = Version.get(reader.readString("@version")); while (reader.next("classpath")) { resources.add("classpath:" + reader.readString("text()")); } i18NResources.add(new I18NResource(name, version, resources)); } return i18NResources; } /** * Import the image resources. * * @param reader The XML reader. * * @return A List containing all the ImageResource of the module. * * @throws XMLException If an exception occurs during XML parsing. */ private static List<ImageResource> importImageResources(XMLOverReader reader) throws XMLException { List<ImageResource> imageResources = CollectionUtils.newList(5); while (reader.next("/config/images/resource")) { String name = reader.readString("@name"); String classpath = reader.readString("classpath"); imageResources.add(new ImageResource(name, "classpath:" + classpath)); } return imageResources; } /** * Import the resources. * * @param reader The XML reader. * * @return A List containing all the Resource of the module. * * @throws XMLException If an exception occurs during XML parsing. */ private List<Resource> importResources(XMLOverReader reader) throws XMLException { List<Resource> resources = CollectionUtils.newList(5); while (reader.next("/config/resources/resource")) { String id = reader.readString("@id"); Version version = Version.get(reader.readString("@version")); String url = reader.readString("@url"); resources.add(resourceService.getOrDownloadResource(id, version, url)); } return resources; } /** * Uninstall the given module. * * @param module The module to uninstall. */ public void uninstallModule(Module module) { ModuleResources resources = moduleService.getResources(module); if (resources != null) { for (I18NResource i18NResource : resources.getI18NResources()) { languageService.releaseResource(i18NResource.getName()); } } } /** * A simple task to load a module from a file. * * @author Baptiste Wicht */ private final class ModuleLoaderTask implements Callable<Module> { private final File file; /** * Construct a new ModuleLoader task for the given file. * * @param file The file to installFromRepository. */ private ModuleLoaderTask(File file) { this.file = file; } @Override public Module call() { try { return installModule(file); } catch (ModuleException e) { OSGiUtils.getService(bundleContext, ErrorService.class).addError(Errors.newError(e)); } return null; } } /** * A Builder for the SimpleModule instance. * * @author Baptiste Wicht */ private final class Builder { private String id; private Bundle bundle; private Version version; private Version coreVersion; private String[] dependencies; private String url; private String updateUrl; private String messagesUrl; private boolean collection; /** * Set the id of the module. * * @param id The id of the module. */ public void setId(String id) { this.id = id; } /** * Set the version of the module. * * @param version The version of the module. */ public void setVersion(Version version) { this.version = version; } /** * Set the core version needed by the module. * * @param coreVersion The core version needed by the module. */ public void setCoreVersion(Version coreVersion) { this.coreVersion = coreVersion; } /** * Set the bundle of the module. * * @param bundle The bundle. */ public void setBundle(Bundle bundle) { this.bundle = bundle; } /** * Set the URL of the site of the module. * * @param url THe URL of the site of the module. */ public void setUrl(String url) { this.url = url; } /** * Set the the URL to the update file of the module. * * @param updateUrl The URL to the update file of the module. */ public void setUpdateUrl(String updateUrl) { this.updateUrl = updateUrl; } /** * Set the dependencies of the module. * * @param dependencies The dependencies of the module. */ public void setDependencies(String[] dependencies) { this.dependencies = ArrayUtils.copyOf(dependencies); } /** * Set the messages URL. * * @param messagesUrl The messages URL of the module. */ public void setMessagesUrl(String messagesUrl) { this.messagesUrl = messagesUrl; } /** * Set the boolean tag indicating if the module is collection-based or not. * * @param collection boolean tag indicating if the module is collection-based (true) or not (false). */ public void setCollection(boolean collection) { this.collection = collection; } /** * Build the module. * * @return The module to build. */ public Module build() { return new SimpleModule(this); } } /** * A module implementation. * * @author Baptiste Wicht */ @Immutable private final class SimpleModule implements Module { private final String id; private final Bundle bundle; private final Version version; private final Version coreVersion; private final String[] dependencies; private final String url; private final String updateUrl; private final String messagesUrl; private final boolean collection; private volatile ModuleState state; /** * Create a module container using the given builder informations. * * @param builder The builder to get the informations from. */ private SimpleModule(Builder builder) { super(); id = builder.id; version = builder.version; coreVersion = builder.coreVersion; bundle = builder.bundle; dependencies = builder.dependencies; url = builder.url; updateUrl = builder.updateUrl; messagesUrl = builder.messagesUrl; collection = builder.collection; state = ModuleState.INSTALLED; } @Override public Bundle getBundle() { return bundle; } @Override public ModuleState getState() { return state; } @Override public void setState(ModuleState state) { this.state = state; } @Override public String getId() { return id; } @Override public String getName() { return internationalize(id + ".name"); } @Override public String getAuthor() { return internationalize(id + ".author"); } @Override public String getDescription() { return internationalize(id + ".description"); } @Override public String getDisplayState() { return internationalize(state.getKey()); } /** * Internationalize the given key. * * @param key The i18n key. * * @return The internationalized message. */ private String internationalize(String key) { return languageService.getMessage(key); } @Override public Version getVersion() { return version; } @Override public Version getCoreVersion() { return coreVersion; } @Override public String getUrl() { return url; } @Override public String getDescriptorURL() { return updateUrl; } @Override public String[] getDependencies() { return ArrayUtils.copyOf(dependencies); } @Override public String getMessagesUrl() { return messagesUrl; } @Override public String toString() { return getName(); } @Override public boolean isCollection() { return collection; } } /** * A module file filter. This filter accept only the JAR files. * * @author Baptiste Wicht */ private static final class ModuleFilter implements FileFilter { @Override public boolean accept(File file) { return file.isFile() && file.getName().toLowerCase(Locale.getDefault()).endsWith(".jar"); } } }