Examples with Partitioner org.janusgraph.diskstorage.cassandra.AbstractCassandraStoreManager.Partitioner used on opensource projects

Example 1 with Partitioner

use of org.janusgraph.diskstorage.cassandra.AbstractCassandraStoreManager.Partitioner in project janusgraph by JanusGraph.

the class AstyanaxKeyColumnValueStore method getKeys.

@Override
public KeyIterator getKeys(KeyRangeQuery query, StoreTransaction txh) throws BackendException {
    // this query could only be done when byte-ordering partitioner is used
    // because Cassandra operates on tokens internally which means that even contiguous
    // range of keys (e.g. time slice) with random partitioner could produce disjoint set of tokens
    // returning ambiguous results to the user.
    Partitioner partitioner = storeManager.getPartitioner();
    if (partitioner != Partitioner.BYTEORDER)
        throw new PermanentBackendException("getKeys(KeyRangeQuery could only be used with byte-ordering partitioner.");
    ByteBuffer start = query.getKeyStart().asByteBuffer(), end = query.getKeyEnd().asByteBuffer();
    RowSliceQuery rowSlice = keyspace.prepareQuery(columnFamily).setConsistencyLevel(getTx(txh).getReadConsistencyLevel().getAstyanax()).withRetryPolicy(retryPolicy.duplicate()).getKeyRange(start, end, null, null, Integer.MAX_VALUE);
    // Astyanax is bad at builder pattern :(
    rowSlice.withColumnRange(query.getSliceStart().asByteBuffer(), query.getSliceEnd().asByteBuffer(), false, query.getLimit());
    // Omit final the query's key end from the result, if present in result
    final Rows<ByteBuffer, ByteBuffer> r;
    try {
        r = ((OperationResult<Rows<ByteBuffer, ByteBuffer>>) rowSlice.execute()).getResult();
    } catch (ConnectionException e) {
        throw new TemporaryBackendException(e);
    }
    Iterator<Row<ByteBuffer, ByteBuffer>> i = Iterators.filter(r.iterator(), new KeySkipPredicate(query.getKeyEnd().asByteBuffer()));
    return new RowIterator(i, query);
}