Examples with AbstractIterator org.apache.cassandra.utils.AbstractIterator used on opensource projects

Example 1 with AbstractIterator

use of org.apache.cassandra.utils.AbstractIterator in project cassandra by apache.

the class HintsBuffer method consumingHintsIterator.

/**
     * Coverts the queue of offsets for the selected host id into an iterator of hints encoded as ByteBuffers.
     */
Iterator<ByteBuffer> consumingHintsIterator(UUID hostId) {
    final Queue<Integer> bufferOffsets = offsets.get(hostId);
    if (bufferOffsets == null)
        return Collections.emptyIterator();
    return new AbstractIterator<ByteBuffer>() {

        private final ByteBuffer flyweight = slab.duplicate();

        protected ByteBuffer computeNext() {
            Integer offset = bufferOffsets.poll();
            if (offset == null)
                return endOfData();
            int totalSize = slab.getInt(offset) + ENTRY_OVERHEAD_SIZE;
            return (ByteBuffer) flyweight.clear().position(offset).limit(offset + totalSize);
        }
    };
}

Example 2 with AbstractIterator

use of org.apache.cassandra.utils.AbstractIterator in project cassandra by apache.

the class Replay method replay.

public static void replay(String keyspace, List<String> arguments, List<String> targetHosts, List<File> resultPaths, String queryStorePath, boolean replayDDLStatements) {
    // how many fql queries should we read in to memory to be able to sort them?
    int readAhead = 200;
    List<ChronicleQueue> readQueues = null;
    List<FQLQueryIterator> iterators = null;
    List<Predicate<FQLQuery>> filters = new ArrayList<>();
    if (keyspace != null)
        filters.add(fqlQuery -> fqlQuery.keyspace() == null || fqlQuery.keyspace().equals(keyspace));
    if (!replayDDLStatements)
        filters.add(fqlQuery -> {
            boolean notDDLStatement = !fqlQuery.isDDLStatement();
            if (!notDDLStatement)
                logger.info("Excluding DDL statement from replaying: {}", ((FQLQuery.Single) fqlQuery).query);
            return notDDLStatement;
        });
    try {
        readQueues = arguments.stream().map(s -> SingleChronicleQueueBuilder.single(s).readOnly(true).build()).collect(Collectors.toList());
        iterators = readQueues.stream().map(ChronicleQueue::createTailer).map(tailer -> new FQLQueryIterator(tailer, readAhead)).collect(Collectors.toList());
        try (MergeIterator<FQLQuery, List<FQLQuery>> iter = MergeIterator.get(iterators, FQLQuery::compareTo, new Reducer());
            QueryReplayer replayer = new QueryReplayer(iter, targetHosts, resultPaths, filters, queryStorePath)) {
            replayer.replay();
        }
    } catch (Exception e) {
        throw new RuntimeException(e);
    } finally {
        if (iterators != null)
            iterators.forEach(AbstractIterator::close);
        if (readQueues != null)
            readQueues.forEach(Closeable::close);
    }
}