Java Options类代码示例

import org.apache.hadoop.util.Options; //导入依赖的package包/类
protected synchronized void open(Path dir,
                                 WritableComparator comparator,
                                 Configuration conf, 
                                 SequenceFile.Reader.Option... options
                                 ) throws IOException {
  Path dataFile = new Path(dir, DATA_FILE_NAME);
  Path indexFile = new Path(dir, INDEX_FILE_NAME);

  // open the data
  this.data = createDataFileReader(dataFile, conf, options);
  this.firstPosition = data.getPosition();

  if (comparator == null) {
    Class<? extends WritableComparable> cls;
    cls = data.getKeyClass().asSubclass(WritableComparable.class);
    this.comparator = WritableComparator.get(cls, conf);
  } else {
    this.comparator = comparator;
  }

  // open the index
  SequenceFile.Reader.Option[] indexOptions =
    Options.prependOptions(options, SequenceFile.Reader.file(indexFile));
  this.index = new SequenceFile.Reader(conf, indexOptions);
}
 

import org.apache.hadoop.util.Options; //导入依赖的package包/类
/**
 * Create a new Writer with the given options.
 * @param conf the configuration to use
 * @param opts the options to create the file with
 * @return a new Writer
 * @throws IOException
 */
public static Writer createWriter(Configuration conf, Writer.Option... opts
                                  ) throws IOException {
  Writer.CompressionOption compressionOption = 
    Options.getOption(Writer.CompressionOption.class, opts);
  CompressionType kind;
  if (compressionOption != null) {
    kind = compressionOption.getValue();
  } else {
    kind = getDefaultCompressionType(conf);
    opts = Options.prependOptions(opts, Writer.compression(kind));
  }
  switch (kind) {
    default:
    case NONE:
      return new Writer(conf, opts);
    case RECORD:
      return new RecordCompressWriter(conf, opts);
    case BLOCK:
      return new BlockCompressWriter(conf, opts);
  }
}
 

import org.apache.hadoop.util.Options; //导入依赖的package包/类
protected synchronized void open(Path dir,
                                 WritableComparator comparator,
                                 Configuration conf, 
                                 SequenceFile.Reader.Option... options
                                 ) throws IOException {
  Path dataFile = new Path(dir, DATA_FILE_NAME);
  Path indexFile = new Path(dir, INDEX_FILE_NAME);

  // open the data
  this.data = createDataFileReader(dataFile, conf, options);
  this.firstPosition = data.getPosition();

  if (comparator == null)
    this.comparator = 
      WritableComparator.get(data.getKeyClass().
                               asSubclass(WritableComparable.class));
  else
    this.comparator = comparator;

  // open the index
  SequenceFile.Reader.Option[] indexOptions =
    Options.prependOptions(options, SequenceFile.Reader.file(indexFile));
  this.index = new SequenceFile.Reader(conf, indexOptions);
}
 

import org.apache.hadoop.util.Options; //导入依赖的package包/类
public Reader(Path dir, Configuration conf,
              SequenceFile.Reader.Option... opts) throws IOException {
  ComparatorOption comparatorOption = 
    Options.getOption(ComparatorOption.class, opts);
  WritableComparator comparator =
    comparatorOption == null ? null : comparatorOption.getValue();
  INDEX_SKIP = conf.getInt("io.map.index.skip", 0);
  open(dir, comparator, conf, opts);
}
 

import org.apache.hadoop.util.Options; //导入依赖的package包/类
/**
 * Override this method to specialize the type of
 * {@link SequenceFile.Reader} returned.
 */
protected SequenceFile.Reader 
  createDataFileReader(Path dataFile, Configuration conf,
                       SequenceFile.Reader.Option... options
                       ) throws IOException {
  SequenceFile.Reader.Option[] newOptions =
    Options.prependOptions(options, SequenceFile.Reader.file(dataFile));
  return new SequenceFile.Reader(conf, newOptions);
}
 

import org.apache.hadoop.util.Options; //导入依赖的package包/类
public Reader(Configuration conf, Option... opts) throws IOException {
  // Look up the options, these are null if not set
  FileOption fileOpt = Options.getOption(FileOption.class, opts);
  InputStreamOption streamOpt = 
    Options.getOption(InputStreamOption.class, opts);
  StartOption startOpt = Options.getOption(StartOption.class, opts);
  LengthOption lenOpt = Options.getOption(LengthOption.class, opts);
  BufferSizeOption bufOpt = Options.getOption(BufferSizeOption.class,opts);
  OnlyHeaderOption headerOnly = 
    Options.getOption(OnlyHeaderOption.class, opts);
  // check for consistency
  if ((fileOpt == null) == (streamOpt == null)) {
    throw new 
      IllegalArgumentException("File or stream option must be specified");
  }
  if (fileOpt == null && bufOpt != null) {
    throw new IllegalArgumentException("buffer size can only be set when" +
                                       " a file is specified.");
  }
  // figure out the real values
  Path filename = null;
  FSDataInputStream file;
  final long len;
  if (fileOpt != null) {
    filename = fileOpt.getValue();
    FileSystem fs = filename.getFileSystem(conf);
    int bufSize = bufOpt == null ? getBufferSize(conf): bufOpt.getValue();
    len = null == lenOpt
      ? fs.getFileStatus(filename).getLen()
      : lenOpt.getValue();
    file = openFile(fs, filename, bufSize, len);
  } else {
    len = null == lenOpt ? Long.MAX_VALUE : lenOpt.getValue();
    file = streamOpt.getValue();
  }
  long start = startOpt == null ? 0 : startOpt.getValue();
  // really set up
  initialize(filename, file, start, len, conf, headerOnly != null);
}
 

import org.apache.hadoop.util.Options; //导入依赖的package包/类
Writer(Configuration conf, Option... opts) throws IOException {
  BlockSizeOption blockSizeOption =
      Options.getOption(BlockSizeOption.class, opts);
  BufferSizeOption bufferSizeOption =
      Options.getOption(BufferSizeOption.class, opts);
  ReplicationOption replicationOption =
      Options.getOption(ReplicationOption.class, opts);

  FileOption fileOption = Options.getOption(FileOption.class, opts);
  AppendIfExistsOption appendIfExistsOption = Options.getOption(
      AppendIfExistsOption.class, opts);
  StreamOption streamOption = Options.getOption(StreamOption.class, opts);

  // check consistency of options
  if ((fileOption == null) == (streamOption == null)) {
    throw new IllegalArgumentException("file or stream must be specified");
  }
  if (fileOption == null && (blockSizeOption != null ||
                             bufferSizeOption != null ||
                             replicationOption != null)) {
    throw new IllegalArgumentException("file modifier options not " +
                                       "compatible with stream");
  }

  FSDataOutputStream out;
  boolean ownStream = fileOption != null;
  if (ownStream) {
    Path p = fileOption.getValue();
    FileSystem fs;
    fs = p.getFileSystem(conf);
    int bufferSize = bufferSizeOption == null ? getBufferSize(conf) :
                     bufferSizeOption.getValue();
    short replication = replicationOption == null ?
                        fs.getDefaultReplication(p) :
                        (short) replicationOption.getValue();
    long blockSize = blockSizeOption == null ? fs.getDefaultBlockSize(p) :
                     blockSizeOption.getValue();

    if (appendIfExistsOption != null && appendIfExistsOption.getValue()
        && fs.exists(p)) {
      // Read the file and verify header details
      try (WALFile.Reader reader =
               new WALFile.Reader(conf, WALFile.Reader.file(p), new Reader.OnlyHeaderOption())){
        if (reader.getVersion() != VERSION[3]) {
          throw new VersionMismatchException(VERSION[3], reader.getVersion());
        }
        sync = reader.getSync();
      }
      out = fs.append(p, bufferSize);
      this.appendMode = true;
    } else {
      out = fs.create(p, true, bufferSize, replication, blockSize);
    }
  } else {
    out = streamOption.getValue();
  }

  init(conf, out, ownStream);
}
 

import org.apache.hadoop.util.Options; //导入依赖的package包/类
public Reader(Configuration conf, Option... opts) throws IOException {
  // Look up the options, these are null if not set
  FileOption fileOpt = Options.getOption(FileOption.class, opts);
  InputStreamOption streamOpt =
      Options.getOption(InputStreamOption.class, opts);
  StartOption startOpt = Options.getOption(StartOption.class, opts);
  LengthOption lenOpt = Options.getOption(LengthOption.class, opts);
  BufferSizeOption bufOpt = Options.getOption(BufferSizeOption.class, opts);
  OnlyHeaderOption headerOnly =
      Options.getOption(OnlyHeaderOption.class, opts);
  // check for consistency
  if ((fileOpt == null) == (streamOpt == null)) {
    throw new
        IllegalArgumentException("File or stream option must be specified");
  }
  if (fileOpt == null && bufOpt != null) {
    throw new IllegalArgumentException("buffer size can only be set when" +
                                       " a file is specified.");
  }
  // figure out the real values
  Path filename = null;
  FSDataInputStream file;
  final long len;
  if (fileOpt != null) {
    filename = fileOpt.getValue();
    FileSystem fs = filename.getFileSystem(conf);
    int bufSize = bufOpt == null ? getBufferSize(conf) : bufOpt.getValue();
    len = null == lenOpt
          ? fs.getFileStatus(filename).getLen()
          : lenOpt.getValue();
    file = openFile(fs, filename, bufSize, len);
  } else {
    len = null == lenOpt ? Long.MAX_VALUE : lenOpt.getValue();
    file = streamOpt.getValue();
  }
  long start = startOpt == null ? 0 : startOpt.getValue();
  // really set up
  initialize(filename, file, start, len, conf, headerOnly != null);
}