org.jgroups.stack

Class GossipRouter

java.lang.Object

org.jgroups.blocks.cs.ReceiverAdapter

org.jgroups.stack.GossipRouter

All Implemented Interfaces:

ConnectionListener, Receiver

public class GossipRouter
extends ReceiverAdapter
implements ConnectionListener

Router for TCP based group comunication (using layer TCP instead of UDP). Instead of the TCP layer sending packets point-to-point to each other member, it sends the packet to the router which - depending on the target address - multicasts or unicasts it to the group / or single member.

This class is especially interesting for applets which cannot directly make connections (neither UDP nor TCP) to a host different from the one they were loaded from. Therefore, an applet would create a normal channel plus protocol stack, but the bottom layer would have to be the TCP layer which sends all packets point-to-point (over a TCP connection) to the router, which in turn forwards them to their end location(s) (also over TCP). A centralized router would therefore have to be running on the host the applet was loaded from.

An alternative for running JGroups in an applet (IP multicast is not allows in applets as of 1.2), is to use point-to-point UDP communication via the gossip server. However, then the appplet has to be signed which involves additional administrative effort on the part of the user.

Note that a GossipRouter is also a good way of running JGroups in Amazon's EC2 environment which (as of summer 09) doesn't support IP multicasting.

Since:

2.1.1

Author:

Bela Ban, Vladimir Blagojevic, Ovidiu Feodorov

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	GossipRouter.Entry

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.concurrent.ConcurrentMap<java.lang.String,java.util.concurrent.ConcurrentMap<Address,GossipRouter.Entry>>	address_mappings
protected int	backlog
protected java.lang.String	bind_addr
protected boolean	emit_suspect_events
protected long	expiry_time
protected boolean	jmx
protected long	linger_timeout
protected Log	log
protected int	port
protected java.util.concurrent.atomic.AtomicBoolean	running
protected BaseServer	server
protected long	sock_read_timeout
protected ThreadFactory	thread_factory
protected java.util.Timer	timer
protected boolean	use_nio

Constructor Summary

Constructors

Constructor and Description
GossipRouter(java.lang.String bind_addr, int local_port)

Method Summary

Modifier and Type	Method and Description
protected void	addAddressMapping(Address sender, java.lang.String group, Address addr, PhysicalAddress phys_addr, java.lang.String logical_name)
int	backlog()
GossipRouter	backlog(int backlog)
java.lang.String	bindAddress()
GossipRouter	bindAddress(java.lang.String addr)
void	connectionClosed(Connection conn, java.lang.String reason)
void	connectionEstablished(Connection conn)
java.lang.String	dumpAddresssMappings()
java.lang.String	dumpRoutingTable()
boolean	emitSuspectEvents()
GossipRouter	emitSuspectEvents(boolean flag)
long	expiryTime()
GossipRouter	expiryTime(long t)
protected void	handleRegister(Address sender, GossipData request)
boolean	jmx()
GossipRouter	jmx(boolean flag)
long	lingerTimeout()
GossipRouter	lingerTimeout(long t)
Address	localAddress()
static void	main(java.lang.String[] args)
int	port()
GossipRouter	port(int port)
protected GossipData	readRequest(ByteArrayDataInputStream in)
void	receive(Address sender, byte[] buf, int offset, int length) Delivers a message from a given sender to the application
protected void	removeAddressMapping(java.lang.String group, Address addr)
protected void	removeFromAddressMappings(Address client_addr)
protected void	route(java.lang.String group, Address dest, byte[] msg, int offset, int length)
boolean	running()
protected void	sendToAllMembersInGroup(java.util.Set<java.util.Map.Entry<Address,GossipRouter.Entry>> dests, byte[] buf, int offset, int len)
protected void	sendToAllMembersInGroup(java.util.Set<java.util.Map.Entry<Address,GossipRouter.Entry>> dests, GossipData request)
protected void	sendToMember(Address dest, byte[] buf, int offset, int len)
protected void	sendToMember(Address dest, GossipData request)
long	socketReadTimeout()
GossipRouter	socketReadTimeout(long t)
void	start() Lifecycle operation.
void	stop() Always called before destroy().
ThreadFactory	threadPoolFactory()
GossipRouter	threadPoolFactory(ThreadFactory f)
boolean	useNio()
GossipRouter	useNio(boolean flag)

Methods inherited from class org.jgroups.blocks.cs.ReceiverAdapter

receive

Methods inherited from class java.lang.Object

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

Field Detail

bind_addr

protected java.lang.String bind_addr

port

protected int port

expiry_time

protected long expiry_time

linger_timeout

protected long linger_timeout

sock_read_timeout

protected long sock_read_timeout

thread_factory

protected ThreadFactory thread_factory

backlog

protected int backlog

jmx

protected boolean jmx

use_nio

protected boolean use_nio

emit_suspect_events

protected boolean emit_suspect_events

server

protected BaseServer server

running

protected final java.util.concurrent.atomic.AtomicBoolean running

timer

protected java.util.Timer timer

log

protected final Log log

address_mappings

protected final java.util.concurrent.ConcurrentMap<java.lang.String,java.util.concurrent.ConcurrentMap<Address,GossipRouter.Entry>> address_mappings

Constructor Detail

GossipRouter

public GossipRouter(java.lang.String bind_addr,
                    int local_port)

Method Detail

localAddress

public Address localAddress()

bindAddress

public java.lang.String bindAddress()

bindAddress

public GossipRouter bindAddress(java.lang.String addr)

port

public int port()

port

public GossipRouter port(int port)

expiryTime

public long expiryTime()

expiryTime

public GossipRouter expiryTime(long t)

lingerTimeout

public long lingerTimeout()

lingerTimeout

public GossipRouter lingerTimeout(long t)

socketReadTimeout

public long socketReadTimeout()

socketReadTimeout

public GossipRouter socketReadTimeout(long t)

threadPoolFactory

public ThreadFactory threadPoolFactory()

threadPoolFactory

public GossipRouter threadPoolFactory(ThreadFactory f)

backlog

public int backlog()

backlog

public GossipRouter backlog(int backlog)

jmx

public boolean jmx()

jmx

public GossipRouter jmx(boolean flag)

useNio

public boolean useNio()

useNio

public GossipRouter useNio(boolean flag)

emitSuspectEvents

public boolean emitSuspectEvents()

emitSuspectEvents

public GossipRouter emitSuspectEvents(boolean flag)

running

public boolean running()

start

public void start()
           throws java.lang.Exception

Lifecycle operation. Called after create(). When this method is called, the managed attributes have already been set.
Brings the Router into a fully functional state.

Throws:

java.lang.Exception

stop

public void stop()

Always called before destroy(). Close connections and frees resources.

dumpRoutingTable

public java.lang.String dumpRoutingTable()

dumpAddresssMappings

public java.lang.String dumpAddresssMappings()

receive

public void receive(Address sender,
                    byte[] buf,
                    int offset,
                    int length)

Description copied from interface: Receiver

Delivers a message from a given sender to the application

Specified by:

receive in interface Receiver

Overrides:

receive in class ReceiverAdapter

Parameters:

sender - The sender of the message

buf - The buffer. An application typically de-serializes data from the buffer into objects used by the application. Note that when receive() returns, it is not safe to use the buffer any longer; if an application needs to use a buffer after this callback returns, it must make a copy.

offset - The offset at which the received data starts

length - The length of the received data

connectionClosed

public void connectionClosed(Connection conn,
                             java.lang.String reason)

Specified by:

connectionClosed in interface ConnectionListener

connectionEstablished

public void connectionEstablished(Connection conn)

Specified by:

connectionEstablished in interface ConnectionListener

readRequest

protected GossipData readRequest(ByteArrayDataInputStream in)

handleRegister

protected void handleRegister(Address sender,
                              GossipData request)

addAddressMapping

protected void addAddressMapping(Address sender,
                                 java.lang.String group,
                                 Address addr,
                                 PhysicalAddress phys_addr,
                                 java.lang.String logical_name)

removeAddressMapping

protected void removeAddressMapping(java.lang.String group,
                                    Address addr)

removeFromAddressMappings

protected void removeFromAddressMappings(Address client_addr)

route

protected void route(java.lang.String group,
                     Address dest,
                     byte[] msg,
                     int offset,
                     int length)

sendToAllMembersInGroup

protected void sendToAllMembersInGroup(java.util.Set<java.util.Map.Entry<Address,GossipRouter.Entry>> dests,
                                       GossipData request)

sendToAllMembersInGroup

protected void sendToAllMembersInGroup(java.util.Set<java.util.Map.Entry<Address,GossipRouter.Entry>> dests,
                                       byte[] buf,
                                       int offset,
                                       int len)

sendToMember

protected void sendToMember(Address dest,
                            GossipData request)

sendToMember

protected void sendToMember(Address dest,
                            byte[] buf,
                            int offset,
                            int len)

main

public static void main(java.lang.String[] args)
                 throws java.lang.Exception

Throws:

java.lang.Exception