# Package org.apache.cassandra.utils

Interface Summary
Interface | Description
--- | ---
CloseableIterator<T> |
IFilter |
IMergeIterator<In,Out> |
ObjectSizes.MemoryLayoutSpecification | Describes constant memory overheads for various constructs in a JVM implementation.
OutputHandler |

Class Summary
Class | Description
--- | ---
Allocator |
AlwaysPresentFilter |
BackgroundActivityMonitor |
BiMultiValMap<K,V> | A variant of BiMap which does not enforce uniqueness of values.
BloomFilter |
BooleanSerializer |
BoundedStatsDeque | bounded threadsafe deque

ByteBufferUtil

Utility methods to make ByteBuffers less painful The following should illustrate the different ways byte buffers can be used public void testArrayOffet() { byte[] b = "test_slice_array".getBytes(); ByteBuffer bb = ByteBuffer.allocate(1024); assert bb.position() == 0; assert bb.limit() == 1024; assert bb.capacity() == 1024; bb.put(b); assert bb.position() == b.length; assert bb.remaining() == bb.limit() - bb.position(); ByteBuffer bb2 = bb.slice(); assert bb2.position() == 0; //slice should begin at other buffers current position assert bb2.arrayOffset() == bb.position(); //to match the position in the underlying array one needs to //track arrayOffset assert bb2.limit()+bb2.arrayOffset() == bb.limit(); assert bb2.remaining() == bb.remaining(); } }

BytesReadTracker | This class is to track bytes read from given DataInput
CLibrary |
CounterId |
CounterId.CounterIdRecord |
CounterId.OneShotRenewer |
DefaultDouble |
DefaultInteger |
EstimatedHistogram |
EstimatedHistogram.EstimatedHistogramSerializer |
ExpiringMap<K,V> |
ExpiringMap.CacheableObject<T> |
FBUtilities |
FilterFactory |
GuidGenerator |
HeapAllocator |
Hex |
HistogramBuilder | Simple class for constructing an EsimtatedHistogram from a set of predetermined values
Interval<C,D> |
IntervalTree<C,D,I extends Interval<C,D>> |
IntervalTree.Serializer<C,D,I extends Interval<C,D>> |
LatencyTracker |
MD5Digest | The result of the computation of an MD5 digest.
MergeIterator<In,Out> | Merges sorted input iterators which individually contain unique items.
MergeIterator.Candidate<In> |
MergeIterator.Reducer<In,Out> | Accumulator that collects values of type A, and outputs a value of type B.
MerkleTree | A MerkleTree implemented as a binary tree.
MerkleTree.MerkleTreeSerializer |
MerkleTree.RowHash | Hash value representing a row, to be used to pass hashes to the MerkleTree.
MerkleTree.TreeDifference |
MerkleTree.TreeRange | The public interface to a range in the tree.
MerkleTree.TreeRangeIterator | Returns the leaf (range) of a given tree in increasing order.
Murmur3BloomFilter |
Murmur3BloomFilter.Murmur3BloomFilterSerializer |
MurmurHash | This is a very fast, non-cryptographic hash suitable for general hash-based lookup.
Mx4jTool | If mx4j-tools is in the classpath call maybeLoad to load the HTTP interface of mx4j.
ObjectSizes | Modified version of the code from.
OutputHandler.LogOutput |
OutputHandler.SystemOutput |
Pair<T1,T2> |
PureJavaCrc32 | A pure-java implementation of the CRC32 checksum that uses the same polynomial as the built-in native CRC32.
ResourceWatcher |
ResourceWatcher.WatchedResource |
SemanticVersion | Implements semantic versioning as defined at http://semver.org/.
SimpleCondition |
SkipNullRepresenter |
SlabAllocator | The SlabAllocator is a bump-the-pointer allocator that allocates large (2MB by default) regions and then doles them out to threads that request slices into the array.
SortedBiMultiValMap<K,V> |
StatusLogger |
StreamingHistogram | Histogram that can be constructed from streaming of data.
StreamingHistogram.StreamingHistogramSerializer |
UUIDGen | The goods are here: www.ietf.org/rfc/rfc4122.txt.
UUIDSerializer |
WrappedRunnable |