hadoop S3AFileStatus 源码

haddop S3AFileStatus 代码

文件路径：/hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/S3AFileStatus.java

/**
 * 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.s3a;

import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.fs.EtagSource;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.Path;

/**
 * File status for an S3A "file".
 * Modification time is trouble, see {@link #getModificationTime()}.
 *
 * The subclass is private as it should not be created directly.
 */
@InterfaceAudience.Private
@InterfaceStability.Evolving
public class S3AFileStatus extends FileStatus implements EtagSource {

  private static final long serialVersionUID = -5955674081978903922L;

  private Tristate isEmptyDirectory;
  private String eTag;
  private String versionId;

  /**
   * Create a directory status.
   * @param isemptydir is this an empty directory?
   * @param path the path
   * @param owner the owner
   */
  public S3AFileStatus(boolean isemptydir,
      Path path,
      String owner) {
    this(Tristate.fromBool(isemptydir), path, owner);
  }

  /**
   * Create a directory status.
   * @param isemptydir is this an empty directory?
   * @param path the path
   * @param owner the owner
   */
  public S3AFileStatus(Tristate isemptydir,
      Path path,
      String owner) {
    this(path,
        true,
        isemptydir,
        0,
        0,
        0,
        owner,
        null,
        null
    );
  }

  /**
   * A simple file.
   * @param length file length
   * @param modification_time mod time
   * @param path path
   * @param blockSize block size
   * @param owner owner
   * @param eTag eTag of the S3 object if available, else null
   * @param versionId versionId of the S3 object if available, else null
   */
  public S3AFileStatus(long length, long modification_time, Path path,
      long blockSize, String owner, String eTag, String versionId) {
    this(path,
        false,
        Tristate.FALSE,
        length,
        modification_time,
        blockSize,
        owner,
        eTag,
        versionId
    );
  }

  /**
   * Either a file or directory.
   * @param path path
   * @param isDir is this a directory?
   * @param isemptydir is this an empty directory?
   * @param length file length
   * @param modificationTime mod time
   * @param blockSize block size
   * @param owner owner
   * @param eTag eTag of the S3 object if available, else null
   * @param versionId versionId of the S3 object if available, else null
   */
  S3AFileStatus(Path path,
      boolean isDir,
      Tristate isemptydir,
      long length,
      long modificationTime,
      long blockSize,
      String owner,
      String eTag,
      String versionId) {
    super(length, isDir, 1, blockSize, modificationTime,
        0, null, owner, owner, null,
        path, false, true, false);
    this.isEmptyDirectory = isemptydir;
    this.eTag = eTag;
    this.versionId = versionId;
  }

  /**
   * Convenience constructor for creating from a vanilla FileStatus plus
   * an isEmptyDirectory flag.
   * @param source FileStatus to convert to S3AFileStatus
   * @param isEmptyDirectory TRUE/FALSE if known to be / not be an empty
   *     directory, UNKNOWN if that information was not computed.
   * @param eTag eTag of the S3 object if available, else null
   * @param versionId versionId of the S3 object if available, else null
   * @return a new S3AFileStatus
   */
  public static S3AFileStatus fromFileStatus(FileStatus source,
      Tristate isEmptyDirectory, String eTag, String versionId) {
    if (source.isDirectory()) {
      return new S3AFileStatus(isEmptyDirectory, source.getPath(),
          source.getOwner());
    } else {
      return new S3AFileStatus(source.getLen(), source.getModificationTime(),
          source.getPath(), source.getBlockSize(), source.getOwner(),
          eTag, versionId);
    }
  }


  /**
   * @return FALSE if status is not a directory, or its a dir, but known to
   * not be empty.  TRUE if it is an empty directory.  UNKNOWN if it is a
   * directory, but we have not computed whether or not it is empty.
   */
  public Tristate isEmptyDirectory() {
    return isEmptyDirectory;
  }

  /**
   * Update isEmptyDirectory attribute.
   * @param isEmptyDirectory new isEmptyDirectory value
   */
  public void setIsEmptyDirectory(Tristate isEmptyDirectory) {
    this.isEmptyDirectory = isEmptyDirectory;
  }

  /**
   * @return the S3 object eTag when available, else null.
   * @deprecated use {@link EtagSource#getEtag()} for
   * public access.
   */
  @Deprecated
  public String getETag() {
    return getEtag();
  }

  @Override
  public String getEtag() {
    return eTag;
  }

  /**
   * @return the S3 object versionId when available, else null.
   */
  public String getVersionId() {
    return versionId;
  }

  /**
   * set the S3 object versionId, else null.
   * @param versionId version ID or null.
   */
  public void setVersionId(final String versionId) {
    this.versionId = versionId;
  }

  /** Compare if this object is equal to another object.
   * @param   o the object to be compared.
   * @return  true if two file status has the same path name; false if not.
   */
  @Override
  public boolean equals(Object o) {
    return super.equals(o);
  }
  
  /**
   * Returns a hash code value for the object, which is defined as
   * the hash code of the path name.
   *
   * @return  a hash code value for the path name.
   */
  @Override
  public int hashCode() {
    return super.hashCode();
  }

  /** Get the modification time of the file/directory.
   *
   * s3a uses objects as "fake" directories, which are not updated to
   * reflect the accurate modification time. We choose to report the
   * current time because some parts of the ecosystem (e.g. the
   * HistoryServer) use modification time to ignore "old" directories.
   *
   * @return for files the modification time in milliseconds since January 1,
   *         1970 UTC or for directories the current time.
   */
  @Override
  public long getModificationTime(){
    if(isDirectory()){
      return System.currentTimeMillis();
    } else {
      return super.getModificationTime();
    }
  }

  @Override
  public String toString() {
    return super.toString()
        + String.format(" isEmptyDirectory=%s", isEmptyDirectory().name()
        + String.format(" eTag=%s", eTag)
        + String.format(" versionId=%s", versionId));
  }

}

相关信息

hadoop 源码目录

相关文章

hadoop AWSBadRequestException 源码

hadoop AWSClientIOException 源码

hadoop AWSCredentialProviderList 源码

hadoop AWSNoResponseException 源码

hadoop AWSRedirectException 源码

hadoop AWSS3IOException 源码

hadoop AWSServiceIOException 源码

hadoop AWSServiceThrottledException 源码

hadoop AWSStatus500Exception 源码

hadoop AnonymousAWSCredentialsProvider 源码