Package org.jgroups.protocols

Provides implementations of transport protocols which are responsible for sending and receiving messages to/from the network.

Interface Summary

Interface	Description
Bundler	Pluggable way to collect messages and send them as batches
COUNTER.Request
FD_HOST.PingCommand	Command used to check whether a given host is alive, periodically called
LocalTransport	A local transport is used for sending messages only to single (or all) members of the same host.
SSL_KEY_EXCHANGE.SessionVerifier
SWIFT_PING.Authenticator	Contract for Swift authentication providers
TUNNEL.TUNNELPolicy

Class Summary

Class	Description
AlternatingBundler	Bundler implementation which sends message batches (or single messages) as soon as the target destination changes (or max_bundler_size would be exceeded). Messages are removed from the main queue one by one and processed as follows: A B B C C A causes the following sends: A -> {CC} -> {BB} -> A Note that null is also a valid destination (send-to-all). JIRA: https://issues.redhat.com/browse/JGRP-2171
ASYM_ENCRYPT	Encrypts and decrypts communication in JGroups by using a secret key distributed to all cluster members by the key server (coordinator) using asymmetric (public/private key) encryption. The secret key is identical for all cluster members and is used to encrypt messages when sending and decrypt them when receiving messages.
AsyncNoBundler	Simple and stupid async version of NoBundler.
AUTH	The AUTH protocol adds a layer of authentication to JGroups.
AuthHeader	AuthHeader is a holder object for the token that is passed from the joiner to the coordinator
BARRIER	All messages up the stack have to go through a barrier (read lock, RL).
BaseBundler	Implements storing of messages in a hashmap and sending of single messages and message batches.
BasicTCP	Shared base class for TCP protocols
BATCH	Batches messages near the top of the stack.
BATCH.BatchHeader
BATCH2	Batches messages near the top of the stack.
BATCH2.Batch2Header
BatchBundler	Bundler based on BATCH.
BPING	Broadcast PING.
CENTRAL_LOCK	Deprecated. See http://belaban.blogspot.com/2020/11/i-hate-distributed-locks.html.
CENTRAL_LOCK2	Deprecated. See http://belaban.blogspot.com/2020/11/i-hate-distributed-locks.html.
CertficateCNMatcher	Sample implementation of SSL_KEY_EXCHANGE.SessionVerifier
CLEAR_FLAGS	Protocol which clears the given flags in the down direction for all messages
COMPRESS	Compresses the payload of a message.
COMPRESS.CompressHeader
COUNTER	Protocol which is used by CounterService to provide a distributed atomic counter
COUNTER.AddAndGetRequest
COUNTER.CompareAndSetRequest
COUNTER.CounterHeader
COUNTER.CounterViewImpl
COUNTER.DeleteRequest
COUNTER.ExceptionResponse
COUNTER.GetOrCreateRequest
COUNTER.ReconcileRequest
COUNTER.ReconcileResponse
COUNTER.RequestCompletableFuture<T>
COUNTER.ResendPendingRequests
COUNTER.Response<T>
COUNTER.ResponseData<T>
COUNTER.SetRequest
COUNTER.SimpleRequest
COUNTER.SyncCounterImpl
COUNTER.UpdateFunctionRequest<T extends Streamable>
COUNTER.UpdateFunctionResponse<T extends Streamable>
COUNTER.UpdateRequest
COUNTER.UpdateResult<T extends Streamable>
COUNTER.ValueResponse
COUNTER.VersionedValue
DAISYCHAIN	Implementation of daisy chaining.
DAISYCHAIN.DaisyHeader
DELAY	Delays incoming/outgoing messages by a random number of milliseconds (range between 0 and n where n is determined by the user) and nanoseconds (constant amount).
DETECT_LOOPBACKS	Detects unicast loopbacks: messages where dest == local address
DH_KEY_EXCHANGE	Key exchange based on Diffie-Hellman-Merkle (https://en.wikipedia.org/wiki/Diffie%E2%80%93Hellman_key_exchange). Diffie-Hellman is used between a member and a key server (the coordinator) to obtain a session key (only known to the key server and the joiner) which is used by the key server to encrypt the shared secret symmetric (group) key and by the requester to decrypt the group key it gets in the response of the key server.
DH_KEY_EXCHANGE.DhHeader
DISCARD	Discards up or down messages based on a percentage; e.g., setting property 'up' to 0.1 causes 10% of all up messages to be discarded.
DISCARD_PAYLOAD	Discards a message whose sequence number (in the payload, as a Long) matches seqno 2 times, before passing it down.
DISCARD.MyCheckBox
Discovery	The Discovery protocol retrieves the initial membership (used by GMS and MERGE3) by sending discovery requests.
DROP	Protocol which drops up or down messages according to user-defined filters
DUPL	Duplicates outgoing or incoming messages by copying them
Encrypt<E extends java.security.KeyStore.Entry>	Super class of symmetric (SYM_ENCRYPT) and asymmetric (ASYM_ENCRYPT) encryption protocols.
EncryptHeader
EXAMPLE	Example of a protocol layer.
EXAMPLE.ExampleHeader
FailureDetection
FailureDetection.HeartbeatHeader
FcHeader	Header used by various flow control protocols
FD_ALL	Failure detection based on simple heartbeat protocol.
FD_ALL2	Failure detection based on simple heartbeat protocol.
FD_ALL3	Failure detection based on simple heartbeat protocol.
FD_ALL3.Bitmap
FD_HOST	Failure detection protocol which detects the crash or hanging of entire hosts and suspects all cluster members on those hosts.
FD_HOST.CommandExecutor2
FD_HOST.ExternalPingCommand
FD_HOST.IsReachablePingCommand
FD_SOCK	Failure detection protocol based on sockets.
FD_SOCK.ClientConnectionHandler	Handles a client connection; multiple client can connect at the same time
FD_SOCK.FdHeader
FD_SOCK2	Failure detection protocol based on TCP connections, successor to FD_SOCK.
FD_SOCK2.FdHeader
FD_SOCK2.PingDest
FD_SOCK2.Request
FILE_PING	Simple discovery protocol which uses a file on shared storage such as an SMB share, NFS mount or S3.
FlowControl	Simple flow control protocol based on a credit system.
FORK	The FORK protocol; multiplexes messages to different forks in a stack (https://issues.redhat.com/browse/JGRP-1613).
FORK.ForkHeader
FRAG	Fragmentation layer.
FRAG.FragmentationList	A fragmentation list keeps a list of fragmentation tables sorted by an Address ( the sender ).
FRAG.FragmentationTable	Keeps track of the fragments that are received.
FRAG.FragmentationTable.FragEntry	inner class represents an entry for a message each entry holds an array of byte arrays sorted once all the byte buffer entries have been filled the fragmentation is considered complete.
FRAG2	Fragmentation layer.
FRAG2.FragEntry	Class represents an entry for a message.
FRAG3	Fragmentation protocol which uses less memory to store fragments than FRAG2. When a message is fragmented, all fragments carry the size of the original message, their offset and length with respect to the original message and a fragment ID (to identify the fragment). When the first fragment is received, the full message is created and each fragment copies its data into the full message at its offset and length.
Frag3Header
FRAG4	Fragmentation layer.
FragHeader
Fragmentation	Base class for all fragmentation protocols.
HDRS	Prints the headers of all sent or received messages
INJECT_VIEW	Simple protocol to inject an arbitrary view on one or more cluster nodes.
JDBC_PING	Discovery protocol using a JDBC connection to a shared database.
KeyExchange	Base class for protocols implementing key exchange: a secret key to be used for encryption is exchanged between 2 parties (usually the key server and a new cluster member) securely; ie.
LOCAL_PING	Discovery protocol for finding members in the local process only.
Locking	Deprecated. See http://belaban.blogspot.com/2020/11/i-hate-distributed-locks.html.
Locking.LockInfoResponse
Locking.LockingHeader
Locking.Request
Locking.Response	A response to a request, to be sent back to the requester as a message
MAKE_BATCH	Intercepts individual up messages and creates batches from them, passing the batches up.
MERGE3	Protocol to discover subgroups; e.g., existing due to a network partition (that healed).
MERGE3.MergeHeader
MFC	Simple flow control protocol based on a credit system.
MFC_NB	Non-blocking alternative to MFC. JIRA: JIRA: https://issues.redhat.com/browse/JGRP-2172
MPING	Uses its own IP multicast socket to send and receive discovery requests/responses.
MsgStats	Class which has all the stats about received/sent messages etc (in TP)
NoBundler	Bundler which doesn't bundle :-) Can be used to measure the diff between bundling and non-bundling (e.g.
PDC	Persistent Discovery Cache.
PDC.Mapping
PERF	Protocol measuring latency between stacks.
PERF.PerfHeader
PING	The PING protocol retrieves the initial membership by mcasting a discovery request (via the multicast capable transport) to all current cluster members
PingData	Encapsulates information about a cluster node, e.g.
PingHeader	Used to send discovery requests and responses
RACKSPACE_PING	Discovery protocol based on Rackspace Cloud Files storage solution
RACKSPACE_PING.RackspaceClient	A thread safe Rackspace ReST client
RATE_LIMITER	Protocol which sends at most max_bytes in time_period milliseconds.
RED	Implementation of Random Early Drop: messages are discarded when the bundler's queue in the transport nears exhaustion.
RemoveQueueBundler	Bundler implementation which sends message batches (or single messages) as soon as the remove queue is full (or max_bundler_size would be exceeded). Messages are removed from the main queue and processed as follows (assuming they all fit into the remove queue): A B B C C A causes the following sends: {AA} -> {CC} -> {BB} Note that null is also a valid destination (send-to-all). Contrary to TransferQueueBundler, this bundler uses a RingBuffer rather than an ArrayBlockingQueue and the size of the remove queue is fixed.
REVERSE	Reverses the next N messages that are received.
RingBufferBundler	Bundler which uses RingBuffer to store messages.
RingBufferBundlerLockless	Bundler which doesn't use locks but relies on CAS.
RingBufferBundlerLockless2	Lockless bundler using a reader thread which is unparked by (exactly one) writer thread.
RSVP	Protocol which implements synchronous messages (https://issues.redhat.com/browse/JGRP-1389).
RSVP.Entry
RSVP.RsvpHeader
RTTHeader	Header to measure round-trip times (in nanoseconds) for sync RPCs (https://issues.redhat.com/browse/JGRP-2604)
SenderSendsBundler
SEQUENCER	Implementation of total order protocol using a sequencer.
SEQUENCER.SequencerHeader
SEQUENCER2	Implementation of total order protocol using a sequencer_uum.
SEQUENCER2.SequencerHeader
SERIALIZE	Serializes the entire message (including payload, headers, flags and destination and src) into the payload of another message that's then sent.
SHARED_LOOPBACK	Loopback transport shared by all channels within the same VM.
SHARED_LOOPBACK_PING	Discovery protocol running over SHARED_LOOPBACK only.
SHUFFLE	Reorders messages by buffering them and shuffling the result after TIMEOUT ms.
SimpleTCP	Bare-bones thread-per-connection TCP-based transport.
SimplifiedTransferQueueBundler	This bundler uses the same logic as TransferQueueBundler but does not allocate memory except for the buffer itself and does not use complex data structures.
SIZE	Protocol which prints out the real size of a message.
SNIFF	Protocol trying to print message payloads as strings
SOS	Periodically fetches some attributes and writes them to a file (https://issues.redhat.com/browse/JGRP-2402)
SSL_KEY_EXCHANGE	Key exchange based on SSL sockets.
STATS	Provides various stats
STOMP	Protocol which provides STOMP (http://stomp.codehaus.org/) support.
STOMP.Frame
STOMP.StompHeader
SWIFT_PING	Discovery protocol based on Openstack Swift (object storage).
SWIFT_PING.ConnBuilder	Build HttpURLConnections with adequate headers and method
SWIFT_PING.Credentials	Result of a successfully authenticated session
SWIFT_PING.HttpHeaders
SWIFT_PING.HttpResponse	Response for a Swift API call
SWIFT_PING.Keystone_V_2_0_Auth	Openstack Keytsone v2.0 authentication provider.
SWIFT_PING.SwiftClient	A thread safe Swift client
SWIFT_PING.Utils
SYM_ENCRYPT	Encrypts and decrypts communication in JGroups by using a secret key shared by all cluster members.
TCP	TCP based protocol.
TCP_NIO2	Protocol using TCP/IP to send and receive messages.
TCPGOSSIP	The TCPGOSSIP protocol layer retrieves the initial membership (used by GMS when started by sending event FIND_INITIAL_MBRS down the stack).
TCPPING	The TCPPING protocol defines a static cluster membership.
TIME	Protocol measuring delivery times.
TP	Generic transport - specific implementations should extend this abstract class.
TpHeader	Generic transport header, used by TP.
TRACE
TransferQueueBundler	This bundler adds all (unicast or multicast) messages to a queue until max size has been exceeded, but does send messages immediately when no other messages are available.
TransferQueueBundler2	This bundler adds all (unicast or multicast) messages to a queue until max size has been exceeded, but does send messages immediately when no other messages are available.
TransferQueueBundler2.Buffer
TUNNEL	Replacement for UDP.
UDP	IP multicast transport based on UDP.
UFC	Simple flow control protocol based on a credit system.
UFC_NB	Non-blocking alternative to UFC. JIRA: https://issues.redhat.com/browse/JGRP-2172
UNICAST3	Reliable unicast protocol using a combination of positive and negative acks.
UnicastHeader3	Moved out of UNICAST3 into separate class.
VERIFY_SUSPECT	Catches SUSPECT events traveling up the stack.
VERIFY_SUSPECT.Entry
VERIFY_SUSPECT.VerifyHeader
VERIFY_SUSPECT2	Double-checks that a suspected member is really dead. Details: https://issues.redhat.com/browse/JGRP-2558 Design: https://github.com/belaban/JGroups/blob/master/doc/design/VERIFY_SUSPECT2.txt
VERIFY_SUSPECT2.Entry
VERIFY_SUSPECT2.VerifyHeader

Enum Summary

Enum	Description
ASYM_ENCRYPT.Processing
COUNTER.RequestType
COUNTER.ResponseType
DH_KEY_EXCHANGE.Type
DUPL.Direction
FD_SOCK2.Request.Type
FD_SOCK2.State
Locking.Type
MERGE3.MergeHeader.Type
SSL_KEY_EXCHANGE.Type
STOMP.ClientVerb
STOMP.ServerVerb
STOMP.StompHeader.Type
SWIFT_PING.AUTH_TYPE	Supported Swift authentication providers
UNICAST3.State