org.jgroups.protocols

Class ABP

java.lang.Object

org.jgroups.stack.Protocol

org.jgroups.protocols.ABP

public class ABP
extends Protocol

Alternating Bit Protocol. Use without any UNICASTX protocol. Place it somewhere below NAKACKX. Provides reliable p2p unicasting. Design is in ./doc/design/ABP.txt

Since:

3.6.3

Author:

Bela Ban

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	ABP.ABPHeader
protected class	ABP.Entry
protected static class	ABP.Type

Field Summary

Fields

Modifier and Type	Field and Description
protected Address	local_addr
protected java.util.concurrent.ConcurrentHashMap<Address,ABP.Entry>	recv_map
protected long	resend_interval
protected java.util.concurrent.ConcurrentHashMap<Address,ABP.Entry>	send_map
protected TimeScheduler	timer

Fields inherited from class org.jgroups.stack.Protocol

after_creation_hook, down_prot, ergonomics, id, log, name, stack, stats, up_prot

Constructor Summary

Constructors

Constructor and Description
ABP()

Method Summary

Modifier and Type	Method and Description
java.lang.Object	down(Event evt) An event is to be sent down the stack.
protected ABP.Entry	getEntry(java.util.concurrent.ConcurrentMap<Address,ABP.Entry> map, Address dest)
void	init() Called after instance has been created (null constructor) and before protocol is started.
java.lang.Object	up(Event evt) An event was received from the layer below.

Methods inherited from class org.jgroups.stack.Protocol

accept, afterCreationHook, destroy, dumpStats, enableStats, getConfigurableObjects, getDownProtocol, getDownServices, getId, getIdsAbove, getLevel, getLog, getName, getProtocolStack, getSocketFactory, getThreadFactory, getTransport, getUpProtocol, getUpServices, getValue, isErgonomics, level, parse, printStats, providedDownServices, providedUpServices, requiredDownServices, requiredUpServices, resetStatistics, resetStats, setDownProtocol, setErgonomics, setId, setLevel, setProtocolStack, setSocketFactory, setUpProtocol, setValue, setValues, start, statsEnabled, stop, up

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

resend_interval

protected long resend_interval

send_map

protected final java.util.concurrent.ConcurrentHashMap<Address,ABP.Entry> send_map

recv_map

protected final java.util.concurrent.ConcurrentHashMap<Address,ABP.Entry> recv_map

timer

protected TimeScheduler timer

local_addr

protected Address local_addr

Constructor Detail

ABP

public ABP()

Method Detail

init

public void init()
          throws java.lang.Exception

Description copied from class: Protocol

Called after instance has been created (null constructor) and before protocol is started. Properties are already set. Other protocols are not yet connected and events cannot yet be sent.

Overrides:

init in class Protocol

Throws:

java.lang.Exception - Thrown if protocol cannot be initialized successfully. This will cause the ProtocolStack to fail, so the channel constructor will throw an exception

down

public java.lang.Object down(Event evt)

Description copied from class: Protocol

An event is to be sent down the stack. The layer may want to examine its type and perform some action on it, depending on the event's type. If the event is a message MSG, then the layer may need to add a header to it (or do nothing at all) before sending it down the stack using down_prot.down(). In case of a GET_ADDRESS event (which tries to retrieve the stack's address from one of the bottom layers), the layer may need to send a new response event back up the stack using up_prot.up().

Overrides:

down in class Protocol

up

public java.lang.Object up(Event evt)

Description copied from class: Protocol

An event was received from the layer below. Usually the current layer will want to examine the event type and - depending on its type - perform some computation (e.g. removing headers from a MSG event type, or updating the internal membership list when receiving a VIEW_CHANGE event). Finally the event is either a) discarded, or b) an event is sent down the stack using down_prot.down() or c) the event (or another event) is sent up the stack using up_prot.up().

Overrides:

up in class Protocol

getEntry

protected ABP.Entry getEntry(java.util.concurrent.ConcurrentMap<Address,ABP.Entry> map,
                             Address dest)