org.apache.hadoop.hbase.Cell#toString ( )源码实例Demo

public static void doSmokeTest(FileSystem fs, Path path, String codec)
throws Exception {
  Configuration conf = HBaseConfiguration.create();
  HFileContext context = new HFileContextBuilder()
                         .withCompression(HFileWriterImpl.compressionByName(codec)).build();
  HFile.Writer writer = HFile.getWriterFactoryNoCache(conf)
      .withPath(fs, path)
      .withFileContext(context)
      .create();
  // Write any-old Cell...
  final byte [] rowKey = Bytes.toBytes("compressiontestkey");
  Cell c = ExtendedCellBuilderFactory.create(CellBuilderType.DEEP_COPY)
    .setRow(rowKey)
    .setFamily(HConstants.EMPTY_BYTE_ARRAY)
    .setQualifier(HConstants.EMPTY_BYTE_ARRAY)
    .setTimestamp(HConstants.LATEST_TIMESTAMP)
    .setType(KeyValue.Type.Maximum.getCode())
    .setValue(Bytes.toBytes("compressiontestval"))
    .build();
  writer.append(c);
  writer.appendFileInfo(Bytes.toBytes("compressioninfokey"), Bytes.toBytes("compressioninfoval"));
  writer.close();
  Cell cc = null;
  HFile.Reader reader = HFile.createReader(fs, path, CacheConfig.DISABLED, true, conf);
  try {
    HFileScanner scanner = reader.getScanner(false, true);
    scanner.seekTo(); // position to the start of file
    // Scanner does not do Cells yet. Do below for now till fixed.
    cc = scanner.getCell();
    if (CellComparator.getInstance().compareRows(c, cc) != 0) {
      throw new Exception("Read back incorrect result: " + c.toString() + " vs " + cc.toString());
    }
  } finally {
    reader.close();
  }
}
 

/**
 * Create an HFile with the given number of rows between a given
 * start key and end key @ family:qualifier.
 * If withTag is true, we add the rowKey as the tag value for
 * tagtype MOB_TABLE_NAME_TAG_TYPE
 */
public static void createHFile(
    Configuration configuration,
    FileSystem fs, Path path, DataBlockEncoding encoding,
    byte[] family, byte[] qualifier,
    byte[] startKey, byte[] endKey, int numRows, boolean withTag) throws IOException {
  HFileContext meta = new HFileContextBuilder()
      .withIncludesTags(withTag)
      .withDataBlockEncoding(encoding)
      .withColumnFamily(family)
      .build();
  HFile.Writer writer = HFile.getWriterFactory(configuration, new CacheConfig(configuration))
      .withPath(fs, path)
      .withFileContext(meta)
      .create();
  long now = System.currentTimeMillis();
  try {
    // subtract 2 since iterateOnSplits doesn't include boundary keys
    for (byte[] key : Bytes.iterateOnSplits(startKey, endKey, numRows - 2)) {
      Cell kv = new KeyValue(key, family, qualifier, now, key);
      if (withTag) {
        // add a tag.  Arbitrarily chose mob tag since we have a helper already.
        Tag tableNameTag = new ArrayBackedTag(TagType.MOB_TABLE_NAME_TAG_TYPE, key);
        kv = MobUtils.createMobRefCell(kv, key, tableNameTag);

        // verify that the kv has the tag.
        Optional<Tag> tag = PrivateCellUtil.getTag(kv, TagType.MOB_TABLE_NAME_TAG_TYPE);
        if (!tag.isPresent()) {
          throw new IllegalStateException("Tag didn't stick to KV " + kv.toString());
        }
      }
      writer.append(kv);
    }
  } finally {
    writer.appendFileInfo(BULKLOAD_TIME_KEY, Bytes.toBytes(System.currentTimeMillis()));
    writer.close();
  }
}
 

Mutation add(Cell cell) throws IOException {
  //Checking that the row of the kv is the same as the mutation
  // TODO: It is fraught with risk if user pass the wrong row.
  // Throwing the IllegalArgumentException is more suitable I'd say.
  if (!CellUtil.matchingRows(cell, this.row)) {
    throw new WrongRowIOException("The row in " + cell.toString() +
      " doesn't match the original one " +  Bytes.toStringBinary(this.row));
  }

  byte[] family;

  if (cell instanceof IndividualBytesFieldCell) {
    family = cell.getFamilyArray();
  } else {
    family = CellUtil.cloneFamily(cell);
  }

  if (family == null || family.length == 0) {
    throw new IllegalArgumentException("Family cannot be null");
  }

  if (cell instanceof ExtendedCell) {
    getCellList(family).add(cell);
  } else {
    getCellList(family).add(new CellWrapper(cell));
  }
  return this;
}
 

private String toString(Cell kv) {
  return kv.toString() + "/value=" + 
      Bytes.toStringBinary(kv.getValueArray(), kv.getValueOffset(), kv.getValueLength());
}