| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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. |
| */ |
| package org.apache.hadoop.fs; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.conf.Configured; |
| import org.apache.hadoop.util.ReflectionUtils; |
| |
| import java.io.IOException; |
| |
| /** |
| * This interface is used for implementing different Trash policies. |
| * Provides factory method to create instances of the configured Trash policy. |
| */ |
| @InterfaceAudience.Public |
| @InterfaceStability.Evolving |
| public abstract class TrashPolicy extends Configured { |
| protected FileSystem fs; // the FileSystem |
| protected Path trash; // path to trash directory |
| protected long deletionInterval; // deletion interval for Emptier |
| |
| /** |
| * Used to setup the trash policy. Must be implemented by all TrashPolicy |
| * implementations. |
| * @param conf the configuration to be used |
| * @param fs the filesystem to be used |
| * @param home the home directory |
| * @deprecated Use {@link #initialize(Configuration, FileSystem)} instead. |
| */ |
| @Deprecated |
| public abstract void initialize(Configuration conf, FileSystem fs, Path home); |
| |
| /** |
| * Used to setup the trash policy. Must be implemented by all TrashPolicy |
| * implementations. Different from initialize(conf, fs, home), this one does |
| * not assume trash always under /user/$USER due to HDFS encryption zone. |
| * @param conf the configuration to be used |
| * @param fs the filesystem to be used |
| */ |
| public void initialize(Configuration conf, FileSystem fs) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| /** |
| * Returns whether the Trash Policy is enabled for this filesystem. |
| */ |
| public abstract boolean isEnabled(); |
| |
| /** |
| * Move a file or directory to the current trash directory. |
| * @return false if the item is already in the trash or trash is disabled |
| */ |
| public abstract boolean moveToTrash(Path path) throws IOException; |
| |
| /** |
| * Create a trash checkpoint. |
| */ |
| public abstract void createCheckpoint() throws IOException; |
| |
| /** |
| * Delete old trash checkpoint(s). |
| */ |
| public abstract void deleteCheckpoint() throws IOException; |
| |
| /** |
| * Delete all checkpoints immediately, ie empty trash. |
| */ |
| public abstract void deleteCheckpointsImmediately() throws IOException; |
| |
| /** |
| * Get the current working directory of the Trash Policy |
| * This API does not work with files deleted from encryption zone when HDFS |
| * data encryption at rest feature is enabled as rename file between |
| * encryption zones or encryption zone and non-encryption zone is not allowed. |
| * |
| * The caller is recommend to use the new API |
| * TrashPolicy#getCurrentTrashDir(Path path). |
| * It returns the trash location correctly for the path specified no matter |
| * the path is in encryption zone or not. |
| */ |
| public abstract Path getCurrentTrashDir(); |
| |
| /** |
| * Get the current trash directory for path specified based on the Trash |
| * Policy |
| * @param path path to be deleted |
| * @return current trash directory for the path to be deleted |
| * @throws IOException |
| */ |
| public Path getCurrentTrashDir(Path path) throws IOException { |
| throw new UnsupportedOperationException(); |
| } |
| |
| /** |
| * Return a {@link Runnable} that periodically empties the trash of all |
| * users, intended to be run by the superuser. |
| */ |
| public abstract Runnable getEmptier() throws IOException; |
| |
| /** |
| * Get an instance of the configured TrashPolicy based on the value |
| * of the configuration parameter fs.trash.classname. |
| * |
| * @param conf the configuration to be used |
| * @param fs the file system to be used |
| * @param home the home directory |
| * @return an instance of TrashPolicy |
| * @deprecated Use {@link #getInstance(Configuration, FileSystem)} instead. |
| */ |
| @Deprecated |
| public static TrashPolicy getInstance(Configuration conf, FileSystem fs, Path home) { |
| Class<? extends TrashPolicy> trashClass = conf.getClass( |
| "fs.trash.classname", TrashPolicyDefault.class, TrashPolicy.class); |
| TrashPolicy trash = ReflectionUtils.newInstance(trashClass, conf); |
| trash.initialize(conf, fs, home); // initialize TrashPolicy |
| return trash; |
| } |
| |
| /** |
| * Get an instance of the configured TrashPolicy based on the value |
| * of the configuration parameter fs.trash.classname. |
| * |
| * @param conf the configuration to be used |
| * @param fs the file system to be used |
| * @return an instance of TrashPolicy |
| */ |
| public static TrashPolicy getInstance(Configuration conf, FileSystem fs) { |
| Class<? extends TrashPolicy> trashClass = conf.getClass( |
| "fs.trash.classname", TrashPolicyDefault.class, TrashPolicy.class); |
| TrashPolicy trash = ReflectionUtils.newInstance(trashClass, conf); |
| trash.initialize(conf, fs); // initialize TrashPolicy |
| return trash; |
| } |
| } |