コード例 #1
0
  @Override
  public long[] indexRetrieval(Object key, TitanKey pt, InternalTitanTransaction tx) {
    Preconditions.checkArgument(
        pt.isSimple(), "Currently, only simple properties are supported for index retrieval");
    Preconditions.checkArgument(
        pt.hasIndex(), "Cannot retrieve for given property key - it does not have an index");

    long[] vertices = null;

    Preconditions.checkArgument(
        pt.getDataType().isInstance(key),
        "Specified object is incompatible with property data type [" + pt.getName() + "]");

    for (int readAttempt = 0; readAttempt < maxReadRetryAttempts; readAttempt++) {
      try {
        if (pt.isUnique()) {
          ByteBuffer value =
              propertyIndex.get(getIndexKey(key), getKeyedIndexColumn(pt), tx.getTxHandle());
          if (value != null) {
            vertices = new long[1];
            vertices[0] = VariableLong.readPositive(value);
          }
        } else {
          ByteBuffer startColumn = VariableLong.positiveByteBuffer(pt.getID());
          List<Entry> entries =
              propertyIndex.getSlice(
                  getIndexKey(key),
                  startColumn,
                  ByteBufferUtil.nextBiggerBuffer(startColumn),
                  tx.getTxHandle());
          vertices = new long[entries.size()];
          int i = 0;
          for (Entry ent : entries) {
            vertices[i++] = VariableLong.readPositive(ent.getValue());
          }
        }

        break;
      } catch (StorageException e) {
        if (e instanceof TemporaryStorageException) {
          if (readAttempt < maxReadRetryAttempts - 1) temporaryStorageException(e);
          else throw readException(e, maxReadRetryAttempts);
        } else throw readException(e);
      }
    }

    if (vertices == null) return new long[0];
    else return vertices;
  }
コード例 #2
0
 private ByteBuffer getIndexColumn(TitanKey type, long propertyID) {
   assert !type.isUnique();
   return VariableLong.positiveByteBuffer(new long[] {type.getID(), propertyID});
 }
コード例 #3
0
 private ByteBuffer getKeyedIndexColumn(TitanKey type) {
   assert type.isUnique();
   return VariableLong.positiveByteBuffer(type.getID());
 }