public FileChunk getFileCunks()

in tajo-core/tajo-core-pullserver/src/main/java/org/apache/tajo/pullserver/PullServerAuxService.java [548:658]
94 lines of code
18 McCabe index (conditional complexity)

  public FileChunk getFileCunks(Path outDir,
                                      String startKey,
                                      String endKey,
                                      boolean last) throws IOException {
    BSTIndex index = new BSTIndex(new TajoConf());
    BSTIndex.BSTIndexReader idxReader =
        index.getIndexReader(new Path(outDir, "index"));
    idxReader.open();
    Schema keySchema = idxReader.getKeySchema();
    TupleComparator comparator = idxReader.getComparator();

    LOG.info("BSTIndex is loaded from disk (" + idxReader.getFirstKey() + ", "
        + idxReader.getLastKey());

    File data = new File(URI.create(outDir.toUri() + "/output"));
    byte [] startBytes = Base64.decodeBase64(startKey);
    byte [] endBytes = Base64.decodeBase64(endKey);

    Tuple start;
    Tuple end;
    try {
      start = RowStoreUtil.RowStoreDecoder.toTuple(keySchema, startBytes);
    } catch (Throwable t) {
      throw new IllegalArgumentException("StartKey: " + startKey
          + ", decoded byte size: " + startBytes.length, t);
    }

    try {
      end = RowStoreUtil.RowStoreDecoder.toTuple(keySchema, endBytes);
    } catch (Throwable t) {
      throw new IllegalArgumentException("EndKey: " + endKey
          + ", decoded byte size: " + endBytes.length, t);
    }


    if(!comparator.isAscendingFirstKey()) {
      Tuple tmpKey = start;
      start = end;
      end = tmpKey;
    }

    LOG.info("GET Request for " + data.getAbsolutePath() + " (start="+start+", end="+ end +
        (last ? ", last=true" : "") + ")");

    if (idxReader.getFirstKey() == null && idxReader.getLastKey() == null) { // if # of rows is zero
      LOG.info("There is no contents");
      return null;
    }

    if (comparator.compare(end, idxReader.getFirstKey()) < 0 ||
        comparator.compare(idxReader.getLastKey(), start) < 0) {
      LOG.info("Out of Scope (indexed data [" + idxReader.getFirstKey() + ", " + idxReader.getLastKey() +
          "], but request start:" + start + ", end: " + end);
      return null;
    }

    long startOffset;
    long endOffset;
    try {
      startOffset = idxReader.find(start);
    } catch (IOException ioe) {
      LOG.error("State Dump (the requested range: "
          + "[" + start + ", " + end +")" + ", idx min: "
          + idxReader.getFirstKey() + ", idx max: "
          + idxReader.getLastKey());
      throw ioe;
    }
    try {
      endOffset = idxReader.find(end);
      if (endOffset == -1) {
        endOffset = idxReader.find(end, true);
      }
    } catch (IOException ioe) {
      LOG.error("State Dump (the requested range: "
          + "[" + start + ", " + end +")" + ", idx min: "
          + idxReader.getFirstKey() + ", idx max: "
          + idxReader.getLastKey());
      throw ioe;
    }

    // if startOffset == -1 then case 2-1 or case 3
    if (startOffset == -1) { // this is a hack
      // if case 2-1 or case 3
      try {
        startOffset = idxReader.find(start, true);
      } catch (IOException ioe) {
        LOG.error("State Dump (the requested range: "
            + "[" + start + ", " + end +")" + ", idx min: "
            + idxReader.getFirstKey() + ", idx max: "
            + idxReader.getLastKey());
        throw ioe;
      }
    }

    if (startOffset == -1) {
      throw new IllegalStateException("startOffset " + startOffset + " is negative \n" +
          "State Dump (the requested range: "
          + "[" + start + ", " + end +")" + ", idx min: " + idxReader.getFirstKey() + ", idx max: "
          + idxReader.getLastKey());
    }

    // if greater than indexed values
    if (last || (endOffset == -1
        && comparator.compare(idxReader.getLastKey(), end) < 0)) {
      endOffset = data.length();
    }

    FileChunk chunk = new FileChunk(data, startOffset, endOffset - startOffset);
    LOG.info("Retrieve File Chunk: " + chunk);
    return chunk;
  }