import org.elasticsearch.repositories.RepositoriesModule; //导入依赖的package包/类
@SuppressWarnings("unchecked")
public void onModule(RepositoriesModule repositoriesModule) {
    if (System.getSecurityManager() != null) {
        Loggers.getLogger(HdfsPlugin.class).warn("The Java Security Manager is enabled however Hadoop is not compatible with it and thus needs to be disabled; see the docs for more information...");
    }

    String baseLib = detectLibFolder();
    List<URL> cp = getHadoopClassLoaderPath(baseLib);

    ClassLoader hadoopCL = URLClassLoader.newInstance(cp.toArray(new URL[cp.size()]), getClass().getClassLoader());

    Class<? extends Repository> repository = null;
    try {
        repository = (Class<? extends Repository>) hadoopCL.loadClass("org.elasticsearch.repositories.hdfs.HdfsRepository");
    } catch (ClassNotFoundException cnfe) {
        throw new IllegalStateException("Cannot load plugin class; is the plugin class setup correctly?", cnfe);
    }

    repositoriesModule.registerRepository("hdfs", repository, BlobStoreIndexShardRepository.class);
    Loggers.getLogger(HdfsPlugin.class).info("Loaded Hadoop [{}] libraries from {}", getHadoopVersion(hadoopCL), baseLib);
}
 

import org.elasticsearch.repositories.RepositoriesModule; //导入依赖的package包/类
public void onModule(RepositoriesModule repositoriesModule){
    if(settings.getAsBoolean("rackspace.enabled", true)){
        repositoriesModule.registerRepository(CloudFilesRepository.TYPE, CloudFilesRepositoryModule.class);
    }
}
 

import org.elasticsearch.repositories.RepositoriesModule; //导入依赖的package包/类
public void onModule(RepositoriesModule repositoriesModule) {
    if (settings.getAsBoolean("gridfs.repository.enabled", true)) {
        repositoriesModule.registerRepository(GridFsRepository.TYPE, GridFsRepositoryModule.class);
    }
}
 

import org.elasticsearch.repositories.RepositoriesModule; //导入依赖的package包/类
/**
 * Load our repository module into the list, if enabled
 * @param repositoriesModule The repositories module to register ourselves with
 */
public void onModule(RepositoriesModule repositoriesModule) {
    if (settings.getAsBoolean("swift.repository.enabled", true)) {
        repositoriesModule.registerRepository(SwiftRepository.TYPE, SwiftRepository.class, BlobStoreIndexShardRepository.class);
    }
}
 

import org.elasticsearch.repositories.RepositoriesModule; //导入依赖的package包/类
public void onModule(RepositoriesModule repositoriesModule) {
    Loggers.getLogger(RepositorySshPlugin.class).info("trying to register repository-ssh...");
    repositoriesModule.registerRepository(SshRepository.TYPE, SshRepository.class,
        BlobStoreIndexShardRepository.class);
}
 

import org.elasticsearch.repositories.RepositoriesModule; //导入依赖的package包/类
public void onModule(RepositoriesModule repositoriesModule) {
    if (settings.getAsBoolean("cloud.enabled", true)) {
        repositoriesModule.registerRepository(WebdavRepository.TYPE, WebdavRepositoryModule.class);
    }
}
 

import org.elasticsearch.repositories.RepositoriesModule; //导入依赖的package包/类
/**
 * Old-style snapshot/restore extension point. {@code @Deprecated} and {@code final} to act as a signpost for plugin authors upgrading
 * from 2.x.
 *
 * @deprecated implement {@link RepositoryPlugin} instead
 */
@Deprecated
public final void onModule(RepositoriesModule module) {}