org.apache.hadoop.hbase.HConstants#HBASE_TEMP_DIRECTORY源码实例Demo

public MasterFileSystem(Configuration conf) throws IOException {
  this.conf = conf;
  // Set filesystem to be that of this.rootdir else we get complaints about
  // mismatched filesystems if hbase.rootdir is hdfs and fs.defaultFS is
  // default localfs.  Presumption is that rootdir is fully-qualified before
  // we get to here with appropriate fs scheme.
  this.rootdir = CommonFSUtils.getRootDir(conf);
  this.tempdir = new Path(this.rootdir, HConstants.HBASE_TEMP_DIRECTORY);
  // Cover both bases, the old way of setting default fs and the new.
  // We're supposed to run on 0.20 and 0.21 anyways.
  this.fs = this.rootdir.getFileSystem(conf);
  this.walRootDir = CommonFSUtils.getWALRootDir(conf);
  this.walFs = CommonFSUtils.getWALFileSystem(conf);
  CommonFSUtils.setFsDefault(conf, new Path(this.walFs.getUri()));
  walFs.setConf(conf);
  CommonFSUtils.setFsDefault(conf, new Path(this.fs.getUri()));
  // make sure the fs has the same conf
  fs.setConf(conf);
  this.secureRootSubDirPerms = new FsPermission(conf.get("hbase.rootdir.perms", "700"));
  this.isSecurityEnabled = "kerberos".equalsIgnoreCase(conf.get("hbase.security.authentication"));
  // setup the filesystem variable
  createInitialFileSystemLayout();
  HFileSystem.addLocationsOrderInterceptor(conf);
}
 

PathHelper(Configuration conf) {
  this.conf = conf;
  rootDir = new Path(conf.get(HConstants.HBASE_DIR));
  tmpDataDir = new Path(new Path(rootDir, HConstants.HBASE_TEMP_DIRECTORY),
      HConstants.BASE_NAMESPACE_DIR);
  dataDir = new Path(rootDir, HConstants.BASE_NAMESPACE_DIR);
  mobDataDir = new Path(MobUtils.getMobHome(rootDir), HConstants.BASE_NAMESPACE_DIR);
  archiveDataDir = new Path(new Path(rootDir, HConstants.HFILE_ARCHIVE_DIRECTORY),
      HConstants.BASE_NAMESPACE_DIR);
  snapshotDir = new Path(rootDir, HConstants.SNAPSHOT_DIR_NAME);
}
 

/**
 * @param rootDir Path to the root directory where hbase files are stored
 * @param archiveDir Path to the hbase archive directory
 * @param hFileLinkPattern The path of the HFile Link.
 */
public final static HFileLink buildFromHFileLinkPattern(final Path rootDir,
                                                        final Path archiveDir,
                                                        final Path hFileLinkPattern) {
  Path hfilePath = getHFileLinkPatternRelativePath(hFileLinkPattern);
  Path tempPath = new Path(new Path(rootDir, HConstants.HBASE_TEMP_DIRECTORY), hfilePath);
  Path originPath = new Path(rootDir, hfilePath);
  Path mobPath = new Path(new Path(rootDir, MobConstants.MOB_DIR_NAME), hfilePath);
  Path archivePath = new Path(archiveDir, hfilePath);
  return new HFileLink(originPath, tempPath, mobPath, archivePath);
}
 

Path getTmpDir() {
  return new Path(rootDir, HConstants.HBASE_TEMP_DIRECTORY);
}
 

/**
 * Sets version of file system
 *
 * @param fs filesystem object
 * @param rootdir hbase root directory
 * @param version version to set
 * @param wait time to wait for retry
 * @param retries number of times to retry before throwing an IOException
 * @throws IOException e
 */
public static void setVersion(FileSystem fs, Path rootdir, String version,
    int wait, int retries) throws IOException {
  Path versionFile = new Path(rootdir, HConstants.VERSION_FILE_NAME);
  Path tempVersionFile = new Path(rootdir, HConstants.HBASE_TEMP_DIRECTORY + Path.SEPARATOR +
    HConstants.VERSION_FILE_NAME);
  while (true) {
    try {
      // Write the version to a temporary file
      FSDataOutputStream s = fs.create(tempVersionFile);
      try {
        s.write(toVersionByteArray(version));
        s.close();
        s = null;
        // Move the temp version file to its normal location. Returns false
        // if the rename failed. Throw an IOE in that case.
        if (!fs.rename(tempVersionFile, versionFile)) {
          throw new IOException("Unable to move temp version file to " + versionFile);
        }
      } finally {
        // Cleaning up the temporary if the rename failed would be trying
        // too hard. We'll unconditionally create it again the next time
        // through anyway, files are overwritten by default by create().

        // Attempt to close the stream on the way out if it is still open.
        try {
          if (s != null) s.close();
        } catch (IOException ignore) { }
      }
      LOG.info("Created version file at " + rootdir.toString() + " with version=" + version);
      return;
    } catch (IOException e) {
      if (retries > 0) {
        LOG.debug("Unable to create version file at " + rootdir.toString() + ", retrying", e);
        fs.delete(versionFile, false);
        try {
          if (wait > 0) {
            Thread.sleep(wait);
          }
        } catch (InterruptedException ie) {
          throw (InterruptedIOException)new InterruptedIOException().initCause(ie);
        }
        retries--;
      } else {
        throw e;
      }
    }
  }
}
 

/**
 * @return Return the tmp dir this tool writes too.
 */
@VisibleForTesting
public static Path getTmpDir(Configuration conf) throws IOException {
  return new Path(CommonFSUtils.getRootDir(conf), HConstants.HBASE_TEMP_DIRECTORY);
}