Package org.jgroups.util

Provides useful functionality which cannot be assigned to any particular other package.

Interface Summary

Interface	Description
AgeOutCache.Handler<K>
Buffer.Visitor<T>
ProcessingQueue.Handler<T>
RequestTable.Visitor<T>
ResourceManager.IpAddressRep
SizeStreamable	Interface implementing Streamable and returning the size of the marshalled object.
SocketFactory	Factory to create various types of sockets.
Streamable	Implementations of Streamable can add their state directly to the output stream, enabling them to bypass costly serialization
Table.Visitor<T>
ThreadFactory
TimeScheduler	Timer-like interface which allows for execution of tasks.
TimeScheduler.Task	The interface that dynamic tasks (TimeScheduler.scheduleWithDynamicInterval(org.jgroups.util.TimeScheduler.Task)) must implement

Class Summary

Class	Description
AckCollector	Collects acks from a number of nodes, waits for all acks.
AckTable	Manages ACKs from receivers in NAKACK4
AgeOutCache<K>	Cache which removes its elements after a certain time
ArrayIterator<T>	Iterator over an array of elements of type T.
AsciiString	Simple string implemented as a byte[] array.
AsyncExecutor<T>	Used to execute asynchronous tasks, e.g.
AsyncExecutor.Task<T>
Average	Maintains an approximation of an average of positive values by keeping a number of values and overwriting values when new values are added. This class uses lockless algorithms and is thread-safe
AverageMinMax	Measures min and max in addition to average
Base64	Encodes and decodes to and from Base64 notation.
Base64.InputStream	A Base64.InputStream will read data from another java.io.InputStream, given in the constructor, and encode/decode to/from Base64 notation on the fly.
Base64.OutputStream	A Base64.OutputStream will write data to another java.io.OutputStream, given in the constructor, and encode/decode to/from Base64 notation on the fly.
BaseDataOutputStream	Implements DataOutput in a generic manner, so that subclasses can implement specific behavior.
Bits	Class (similar to (and partly copied from) java.nio.Bits) containing helper methods to encode variables (e.g.
BlockingInputStream	Bounded input stream.
BoundedHashMap<K,V>	Bounded linked hashmap; used by SEQUENCER
BoundedList<T>	A bounded subclass of LinkedList, oldest elements are removed once max capacity is exceeded.
Buffer<T>	Base class for message buffers.
Buffer.Options
ByteArray	Byte array with an offset and length. Note that the underlying byte array must not be changed as long as this instance is in use !
ByteArrayDataInputStream	Implements DataInput over a byte[] buffer.
ByteArrayDataOutputStream	Implements DataOutput over a byte[] buffer.
ByteBufferInputStream	Class using ByteBuffer and implementing DataInput.
ByteBufferOutputStream	Class using ByteBuffer and implementing DataOutput.
ConcurrentLinkedBlockingQueue<T>	Attempt at writing a fast transfer queue, which is bounded.
ConcurrentLinkedBlockingQueue2<T>	Attempt at writing a fast transfer queue, which is bounded.
CondVar	A condition variable with methods for (timed) waiting and signalling
Credit	Maintains credits for a unicast destination.
CreditMap	Maintains credits for senders, when credits fall below 0, a sender blocks until new credits have been received.
CustomRejectionPolicy	// TODO: Document this
DefaultSocketFactory	Default implementation, ignores service names
DefaultThreadFactory	Thread factory mainly responsible for naming of threads.
Delayer<T>	Collects actions by key and executes them - if a predicate is true - every N ms.
Digest	A message digest containing - for each member - the highest seqno delivered (hd) and the highest seqno received (hr).
Digest.Entry	Keeps track of one members plus its highest delivered and received seqnos
DirectExecutor
DynamicBuffer<T>	Copy of Table.
ExpiryCache<K>	Cache which maintains timestamps for keys, and methods to remove/replace expired keys.
ExtendedUUID	Subclass of UUID accommodating additional data such as a flag and a small hashmap.
FastArray<T>	Simple
FileWatcher
FixedBuffer<T>	Ring buffer of fixed capacity.
FixedSizeBitSet	Class copied from BitSet.
FlagsUUID	Subclass of UUID accommodating additional data such as a flag.
GenerateGettersAndSetters	Given a class, generates code for getters and setters for all attributes and writes it to stdout
GenerateProfilingScript	Takes a list of methods to profile and generates the Byteman script from them.
GetNetworkInterfaces	Lists all network interfaces on a system
Headers	Helper class providing functions to manipulate the headers array in BaseMessage.
InputStreamAdapter	Extends InputStream from a ByteArrayDataInputStream.
IntHashMap<T>	A hashmap where keys have to be ints.
LazyThreadFactory	Lazily names threads: whenever the address or cluster name is changed, all threads are renamed
LongSizeStreamable	Utility class that implements SizeStreamable and LongSupplier to store a long value.
LongTuple<V>	A tuple with a long (primitive) first value
MaxOneThreadPerSender	MessageProcessingPolicy which processes regular messages and message batches by assigning a max of 1 thread per message from the same sender.
MergeId	ID to uniquely identify a merge
MessageBatch	Represents a message batch; multiple messages from the same sender to the same receiver(s).
MessageCache	A cache associating members and messages
Metrics	Extracts all attributes and methods annotated with ManagedAttribute and returns them as a map of names associated with [getter-method/description tuples].
Metrics.Entry<T>
MockTransport	A dummy implementation of TP
MutableDigest	A mutable version of Digest.
MyReceiver<T>	Generic receiver for a JChannel
NameCache	Maintains the mappings between addresses and logical names (moved out of UUID.cache into a separate class)
NonBlockingCredit	Non-blocking credit for a unicast destination. Instead of blocking when insufficient credits are available for sending a message, this class queues the message and sends it at a later time when enough credits have been received to send it. JIRA: https://issues.redhat.com/browse/JGRP-2172
NonBlockingCreditMap
ObjectInputStreamWithClassloader	Override ObjectInputStream.resolveClass(java.io.ObjectStreamClass) using the passed-in classloader
ObjectWrapperPrimitive	Wraps a primitive object (e.g.
ObjectWrapperSerializable	Wraps an object and its serialized form.
OneTimeAddressGenerator	Implementation of AddressGenerator which is configured with an initial value, and after that random values are generated.
OutputStreamAdapter	Extends OutputStream from a ByteArrayDataOutputStream.
Owner	Represents an 'owner', which is an address and thread ID
PaddedAtomicBoolean
PaddedAtomicInteger
PaddedAtomicLong	Copied from http://mechanical-sympathy.blogspot.ch/2011/08/false-sharing-java-7.html.
PartialOutputStream	Decorates an output stream (DataOutput) and writes only a subset [start..end] (both indices inclusive) of the original data to the underlying output stream. Example:
PassRegularMessagesUpDirectly	MessageProcessingPolicy which passes regular messages and message batches up directly (on the same thread), but passes OOB messages to the thread pool.
ProcessingQueue<T>	A queue with many producers and consumers.
Profiler	Maintains averages for time values measured between Profiler.start() and Profiler.stop().
ProgressCheckRejectionPolicy	Detects
Promise<T>	Allows a thread to submit an asynchronous request and to wait for the result.
PropertiesToAsciidoc	Iterates over all concrete Protocol classes and creates tables with Protocol's properties.
Range
Ref<T>	Keeps a reference to another object
ReloadingX509KeyManager	A X509ExtendedKeyManager which uses a @FileWatcher to check for changes.
ReloadingX509TrustManager	A X509ExtendedTrustManager which uses a @FileWatcher to check for changes.
RequestTable<T>	Table for storing requests associated with monotonically increasing sequence numbers (seqnos).
ResourceManager	Manages resources such as multicast addresses and multicast ports, and TCP ports.
ResponseCollector<T>	Similar to AckCollector, but collects responses from cluster members, not just acks.
ResponseCollectorTask<T>	Task which is seeded with an initial membership.
Responses	Manages responses for the discovery protocol.
Responses.PingDataIterator
RingBuffer<T>	Ring buffer of fixed capacity designed for multiple writers but only a single reader.
RingBufferSeqnoLockless<T>	Ring buffer, implemented with a circular array.
RingBufferSeqnoOld<T>	Ring buffer, implemented with a circular array.
RpcStats	Keeps track of stats for sync and async unicasts and multicasts
RpcStats.Result
RpcStats.RTTStat
Rsp<T>	Class that represents a response from a communication
RspList<T>	Contains responses from all members.
RTT	Measures round-trip times (RTT) between nodes
Runner	Runs a given function in a loop (in a separate thread) until it is stopped
SeqnoList	A bitset of missing messages with a fixed size.
ShutdownRejectedExecutionHandler	ShutdownRejectedExecutionHandler is a decorator RejectedExecutionHandler used in all JGroups ThreadPoolExecutor(s).
SizeBoundedQueue<T>	Blocking FIFO queue bounded by the max number of bytes of all elements.
SizeBoundedQueue.El<T>
SslContextFactory	SslContextFactory.
SslContextFactory.Context
StateTransferResult	Encapsulates the result of a state transfer.
SubmitToThreadPool	Default message processing policy.
SuppressCache<T>	Cache which keeps a timestamp and counter for every key.
SuppressCache.Value
SuppressLog<T>	Log (using SuppressCache) which suppresses (certain) messages from the same member for a given time
Table<T>	A store for elements (typically messages) to be retransmitted or delivered.
Tests	Common functions for all tests
ThreadCreator
ThreadPool	Thread pool based on ThreadPoolExecutor
TimeScheduler3	Implementation of TimeScheduler.
TimeScheduler3.Task
TimeService	Provides a coarse grained time service.
TLS	Component to configure TLS in protocols (TCP and TUNNEL).
TLS.SniMatcherConverter
Triple<V1,V2,V3>	Holds 3 values, useful when we have a map with a key, but more than 1 value and we don't want to create a separate holder object for the values, and don't want to pass the values as a list or array.
Tuple<V1,V2>	Holds 2 values, useful when we have a map with a key, but more than 1 value and we don't want to create a separate holder object for the values, and don't want to pass the values as a list or array.
UnbatchOOBBatches	Same as MaxOneThreadPerSender, but for OOB message batches, every message of the batch is passed to the thread pool separately (https://issues.redhat.com/browse/JGRP-2800).
Util	Collection of various utility routines that can not be assigned to other classes.
UUID	Logical address which is unique over space and time.
WriteVersionTo	Extracts version and codename from pom.xml and writes them to ./classes/JGROUPS_VERSION.properties
XMLSchemaGenerator	Iterates over all concrete Protocol classes and creates XML schema used for validation of configuration files.

Enum Summary

Enum	Description
CompletableFutures	Utility class with CompletableFuture and CompletionStage useful methods.
MessageBatch.Mode
RpcStats.Type
StackType
SuppressLog.Level
TimeScheduler3.TaskType
TLSClientAuth
Util.AddressScope

Exception Summary

Exception	Description
NoProgressException	Exception raised when a threadpool rejects jobs but shows no progress.