tigase.server
Class AbstractMessageReceiver

java.lang.Object
  tigase.server.BasicComponent
      tigase.server.AbstractMessageReceiver

All Implemented Interfaces:

Configurable, XMPPService, MessageReceiver, ServerComponent, StatisticsContainer, VHostListener

Direct Known Subclasses:

AmpComponent, ConnectionManager, EchoComponent, Gateway, MessageRouter, MonitorComponent, SessionManager, StanzaReceiver, StanzaSender, TestComponent

public abstract class AbstractMessageReceiver
extends BasicComponent
implements StatisticsContainer, MessageReceiver

This is an archetype for all classes processing user-level packets. The implementation is designed for a heavy packets processing with internal queues and number of separate threads depending on number of CPUs. Extensions of the class can process normall user packets and administrator packets via ad-hoc commands. Good examples of such components are MUC, PubSub, SessionManager.

The class offers scripting API for administrator ad-hoc commands.

By default it internally uses priority queues which in some rare cases may lead to packets reordering. When this happens and it is unacceptable for the deployment non-priority queues can be used. The queues size is limited and depends on the available memory size.

Packets are processed by processPacket(Packet packet) method which is concurrently called from multiple threads. Created: Tue Nov 22 07:07:11 2005

Version:

$Rev: 2996 $

Author:

Artur Hefczyc

Field Summary

protected static long	HOUR Constant used in time calculation procedures.
static String	INCOMING_FILTERS_PROP_KEY Configuration property key for setting incoming packets filters on the component level.
static String	INCOMING_FILTERS_PROP_VAL Configuration property default vakue with a default incoming packet filter loaded by Tigase server.
static String	MAX_QUEUE_SIZE_PROP_KEY Configuration property key allowing to overwrite a default (memory size dependent) size for the component internal queues.
static Integer	MAX_QUEUE_SIZE_PROP_VAL A default value for max queue size property.
protected int	maxInQueueSize
protected int	maxOutQueueSize
protected static long	MINUTE Constant used in time calculation procedures.
static String	OUTGOING_FILTERS_PROP_KEY Configuration property key for setting outgoing packets filters on the component level.
static String	OUTGOING_FILTERS_PROP_VAL Configuration property default vakue with a default outgoing packet filter loaded by Tigase server.
protected static long	SECOND Constant used in time calculation procedures.

Fields inherited from class tigase.server.BasicComponent

admins, ALL_PROP_KEY, COMMAND_PROP_NODE, scriptCommands, SCRIPTS_DIR_PROP_DEF, SCRIPTS_DIR_PROP_KEY, vHostManager

Fields inherited from interface tigase.conf.Configurable

ADMINS_PROP_KEY, AMP_CLASS_NAME, AUTH_DOMAIN_POOL_CLASS, AUTH_REPO_DOMAINS_PROP_KEY, AUTH_REPO_PARAMS_NODE, AUTH_REPO_POOL_CLASS, AUTH_REPO_URL_PROP_KEY, BOSH_CLUST_COMP_CLASS_NAME, BOSH_COMP_CLASS_NAME, C2S_CLUST_COMP_CLASS_NAME, C2S_COMP_CLASS_NAME, CL_COMP_CLASS_NAME, CLUSTER_CONECT, CLUSTER_CONTR_CLASS_NAME, CLUSTER_LISTEN, CLUSTER_MODE, CLUSTER_NODES, CLUSTER_NODES_PROP_KEY, COMP_PROT_CLASS_NAME, COMPONENT_ID_PROP_KEY, DEF_AMP_NAME, DEF_BOSH_NAME, DEF_C2S_NAME, DEF_CL_COMP_NAME, DEF_CLUST_CONTR_NAME, DEF_COMP_PROT_NAME, DEF_EXT_COMP_NAME, DEF_HOSTNAME_PROP_KEY, DEF_MONITOR_NAME, DEF_S2S_NAME, DEF_SM_NAME, DEF_SRECV_NAME, DEF_SSEND_NAME, DEF_STATS_NAME, DEF_VHOST_MAN_NAME, DERBY_REPO_CLASS_PROP_VAL, DERBY_REPO_URL_PROP_VAL, DRUPAL_REPO_URL_PROP_VAL, DRUPALWP_REPO_CLASS_PROP_VAL, DUMMY_REPO_CLASS_PROP_VAL, EXT_COMP_CLASS_NAME, GEN_ADMINS, GEN_AUTH_DB, GEN_AUTH_DB_URI, GEN_COMP_CLASS, GEN_COMP_NAME, GEN_CONF, GEN_CONFIG, GEN_CONFIG_ALL, GEN_CONFIG_COMP, GEN_CONFIG_CS, GEN_CONFIG_DEF, GEN_CONFIG_SM, GEN_DEBUG, GEN_DEBUG_PACKAGES, GEN_EXT_COMP, GEN_MAX_QUEUE_SIZE, GEN_SCRIPT_DIR, GEN_SM_PLUGINS, GEN_SREC_ADMINS, GEN_SREC_DB, GEN_SREC_DB_URI, GEN_TEST, GEN_TRUSTED, GEN_USER_DB, GEN_USER_DB_URI, GEN_USER_DB_URI_PROP_KEY, GEN_VIRT_HOSTS, HOSTNAMES_PROP_KEY, LIBRESOURCE_REPO_CLASS_PROP_VAL, LIBRESOURCE_REPO_URL_PROP_VAL, MONITOR_CLASS_NAME, MONITOR_CLUST_CLASS_NAME, MONITORING, MYSQL_REPO_CLASS_PROP_VAL, MYSQL_REPO_URL_PROP_VAL, PGSQL_REPO_CLASS_PROP_VAL, PGSQL_REPO_URL_PROP_VAL, ROUTER_COMP_CLASS_NAME, S2S_CLUST_COMP_CLASS_NAME, S2S_COMP_CLASS_NAME, SHARED_AUTH_REPO_PARAMS_PROP_KEY, SHARED_AUTH_REPO_PROP_KEY, SHARED_USER_REPO_PARAMS_PROP_KEY, SHARED_USER_REPO_PROP_KEY, SM_CLUST_COMP_CLASS_NAME, SM_COMP_CLASS_NAME, SRECV_COMP_CLASS_NAME, SSEND_COMP_CLASS_NAME, STANZA_WHITE_CHAR_ACK, STANZA_XMPP_ACK, STATS_CLASS_NAME, STRINGPREP_PROCESSOR, TIGASE_AUTH_REPO_CLASS_PROP_VAL, TIGASE_AUTH_REPO_URL_PROP_VAL, TIGASE_CUSTOM_AUTH_REPO_CLASS_PROP_VAL, TRUSTED_PROP_KEY, USER_DOMAIN_POOL_CLASS, USER_REPO_DOMAINS_PROP_KEY, USER_REPO_PARAMS_NODE, USER_REPO_POOL_CLASS, USER_REPO_POOL_SIZE, USER_REPO_POOL_SIZE_PROP_KEY, USER_REPO_URL_PROP_KEY, VHOST_MAN_CLASS_NAME, XML_REPO_CLASS_PROP_VAL, XML_REPO_URL_PROP_VAL, XMPP_STANZA_ACK

Fields inherited from interface tigase.disco.XMPPService

CMD_FEATURES, DEF_FEATURES, INFO_XMLNS, ITEMS_XMLNS

Constructor Summary

AbstractMessageReceiver()

Method Summary

protected boolean	addOutPacket(Packet packet)
protected boolean	addOutPacketNB(Packet packet) Non blocking version of addOutPacket.
protected boolean	addOutPackets(Queue<Packet> packets)
protected boolean	addOutPacketWithTimeout(Packet packet, ReceiverTimeoutHandler handler, long delay, TimeUnit unit)
boolean	addPacket(Packet packet) Method adds a Packet object to the internal input queue.
boolean	addPacketNB(Packet packet) This is a variant of addPacket(Packet) method which adds Packet to in the internal input queue without blocking.
boolean	addPackets(Queue<Packet> packets) This is a convenience method for adding all packets stored in given queue to the component's internal input queue. The method calls addPacket(Packet) in a loop for each packet in the queue.
void	addRegexRouting(String address) Method adds a new routing address for the component.
protected void	addTimerTask(TimerTask task, long delay)
protected void	addTimerTask(TimerTask task, long delay, TimeUnit unit)
void	clearRegexRoutings() Method clears, removes all the component routing addresses.
void	everyHour() Utility method executed precisely every hour.
void	everyMinute() Utility method executed precisely every minute.
void	everySecond() Utility method executed precisely every second.
Map<String,Object>	getDefaults(Map<String,Object> params) Returns default configuration settings for the component as a Map with keys as configuration property IDs and values as the configuration property values.
protected Integer	getMaxQueueSize(int def)
Set<Pattern>	getRegexRoutings() Method returns a Set with all component's routings as a compiled regular expression patterns.
void	getStatistics(StatisticsList list) Method returns component statistics.
int	hashCodeForPacket(Packet packet) This method decides how incoming packets are distributed among processing threads.
boolean	isInRegexRoutings(String address) Method description
String	newPacketId(String prefix) Method description
int	processingInThreads()
int	processingOutThreads()
int	processingThreads() Deprecated.
void	processOutPacket(Packet packet) By default this method just copies the given packet between queue.
abstract void	processPacket(Packet packet) This is the main Packet processing method.
void	processPacket(Packet packet, Queue<Packet> results) Method description
void	release() Method description
boolean	removeRegexRouting(String address) Method description
void	setMaxQueueSize(int maxQueueSize) Method description
void	setName(String name) Method description
void	setParent(MessageReceiver parent) Method description
void	setProperties(Map<String,Object> props) Sets all configuration properties for object.
void	start() Method description
void	stop() Method description

Methods inherited from class tigase.server.BasicComponent

addComponentDomain, canCallCommand, checkCommandAcl, getComponentId, getDefHostName, getDiscoCategory, getDiscoCategoryType, getDiscoDescription, getDiscoFeatures, getDiscoFeatures, getDiscoInfo, getDiscoInfo, getDiscoItems, getDiscoItems, getName, getScriptItems, getVHostItem, handlesLocalDomains, handlesNameSubdomains, handlesNonLocalDomains, initBindings, initializationCompleted, isAdmin, isLocalDomain, isLocalDomainOrComponent, processScriptCommand, removeComponentDomain, removeServiceDiscoveryItem, setVHostManager, updateServiceDiscoveryItem, updateServiceDiscoveryItem, updateServiceDiscoveryItem

Methods inherited from class java.lang.Object

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

Methods inherited from interface tigase.server.MessageReceiver

getDefHostName

Methods inherited from interface tigase.server.ServerComponent

getComponentId, getName, initializationCompleted

Field Detail

INCOMING_FILTERS_PROP_KEY

public static final String INCOMING_FILTERS_PROP_KEY

Configuration property key for setting incoming packets filters on the component level.

See Also:

Constant Field Values

INCOMING_FILTERS_PROP_VAL

public static final String INCOMING_FILTERS_PROP_VAL

Configuration property default vakue with a default incoming packet filter loaded by Tigase server.

This is a comma-separated list of classes which should be loaded as packet filters. The classes must implement PacketFilterIfc interface.

See Also:

Constant Field Values

MAX_QUEUE_SIZE_PROP_KEY

public static final String MAX_QUEUE_SIZE_PROP_KEY

Configuration property key allowing to overwrite a default (memory size dependent) size for the component internal queues. By default the queue size is adjusted to the available memory size to avoid out of memory errors.

See Also:

Constant Field Values

MAX_QUEUE_SIZE_PROP_VAL

public static final Integer MAX_QUEUE_SIZE_PROP_VAL

A default value for max queue size property. The value is calculated at the server startup time using following formula:
Runtime.getRuntime().maxMemory() / 400000L You can change the default queue size by setting a different value for the MAX_QUEUE_SIZE_PROP_KEY property in the server configuration.

OUTGOING_FILTERS_PROP_KEY

public static final String OUTGOING_FILTERS_PROP_KEY

Configuration property key for setting outgoing packets filters on the component level. This is a comma-separated list of classes which should be loaded as packet filters. The classes must implement PacketFilterIfc interface.

See Also:

Constant Field Values

OUTGOING_FILTERS_PROP_VAL

public static final String OUTGOING_FILTERS_PROP_VAL

Configuration property default vakue with a default outgoing packet filter loaded by Tigase server.

This is a comma-separated list of classes which should be loaded as packet filters. The classes must implement PacketFilterIfc interface.

See Also:

Constant Field Values

SECOND

protected static final long SECOND

Constant used in time calculation procedures. Indicates a second that is 1000 milliseconds.

See Also:

Constant Field Values

MINUTE

protected static final long MINUTE

Constant used in time calculation procedures. Indicates a minute that is 60 SECONDs.

See Also:

Constant Field Values

HOUR

protected static final long HOUR

Constant used in time calculation procedures. Indicates a hour that is 60 MINUTEs.

See Also:

Constant Field Values

maxInQueueSize

protected int maxInQueueSize

maxOutQueueSize

protected int maxOutQueueSize

Constructor Detail

AbstractMessageReceiver

public AbstractMessageReceiver()

Method Detail

processPacket

public abstract void processPacket(Packet packet)

This is the main Packet processing method. It is called concurrently from many threads so implementing it in thread save manner is essential. The method is called for each packet addressed to the component.

Please note, the Packet instance may be processed by different parts of the server, different components or plugins at the same time. Therefore this is very important to tread the Packet instance as unmodifiable object.

Processing in this method is asynchronous, therefore there is no result value. If there are some 'result' packets generated during processing, they should be passed back using addOutPacket(Packet) method.

Parameters:

packet - is an instance of the Packet class passed for processing.

processOutPacket

public void processOutPacket(Packet packet)

By default this method just copies the given packet between queue. This method operates on packets which have been already processed somehow by the component so usually the default action is the best one, however some components in rare cases may choose to process packets differently. In most cases this method should not be overridden.

Parameters:

packet - is an output packet which normally has to go to other component for further processing.

addPacket

public boolean addPacket(Packet packet)

Method adds a Packet object to the internal input queue. Packets from the input queue are later passed to the processPacket(Packet) method. This is a blocking method waiting if necessary for the room if the queue is full.

The method returns a boolean value of true if the packet has been successfully added to the queue and false otherwise.

There can be many queues and many threads processing packets for the component, however the method makes the best effort to guarantee that packets are later processed in the correct order. For example that packets for a single user always end up in the same exact queue. You can tweak the packets distribution among threads by overwriting hashCodeForPacket(Packet) method.
If there is N threads the packets are distributed among thread using following logic:

 int threadNo = Math.abs(hashCodeForPacket(packet) % N);
 

This is a preferred method to be used by most Tigase components. If the queues are full the component should stop and wait for more room. The blocking methods aim to prevent from the system overloading or wasting resources for generating packets which can't be processed anyway.

Specified by:

addPacket in interface MessageReceiver

Parameters:

packet - is a Packet instance being put to the component internal input queue.

Returns:

a boolean value of true if the packet has been successfully added to the queue and false otherwise.

addPacketNB

public boolean addPacketNB(Packet packet)

This is a variant of addPacket(Packet) method which adds Packet to in the internal input queue without blocking.

The method returns a boolean value of true if the packet has been successful added to the queue and false otherwise.

Use of the non-blocking methods is not recommended for most of the components implementations. The only component which is allowed to use them is the server MessageRouter implementation which can not hang on any method. This would cause a dead-lock in the application. All other components must use blocking methods and wait if the system is under so high load that it's queues are full.

See addPacket(Packet) method's documentation for some more details.

Specified by:

addPacketNB in interface MessageReceiver

Parameters:

packet - is a Packet instance being put to the component internal input queue.

Returns:

a boolean value of true if the packet has been successfully added to the queue and false otherwise.

See Also:

AbstractMessageReceiver.addPacket(Packet packet)

addPackets

public boolean addPackets(Queue<Packet> packets)

This is a convenience method for adding all packets stored in given queue to the component's internal input queue.
The method calls addPacket(Packet) in a loop for each packet in the queue. If the call returns true then the packet is removed from the given queue, otherwise the methods ends the loop and returns false.

Please note, if the method returns true it means that all the packets from the queue passed as a parameter have been successfuly run through the addPacket(Packet) method and the queue passed as a parameter should be empty. If the method returns false then at least one packet from the parameter queue wasn't successfully run through the addPacket(Packet) method. If the method returns false then the queue passed as a parameter is not empty and it contains packet which was unseccessfully run through the addPacket(Packet) method and all the packets which were not run at all.

Specified by:

addPackets in interface MessageReceiver

Parameters:

packets - is a Queue of packets for adding to the component internal input queue. All the packets are later processed by processPacket(Packet) method in the same exact order if they are processed by the same thread. See documentation hashCodeForPacket(Packet) method how to control assiging packets to particular threads.

Returns:

a boolean value of true if all packets has been successfully added to the component's internal input queue and false otherwise.

See Also:

AbstractMessageReceiver.hashCodeForPacket(Packet packet)

addRegexRouting

public void addRegexRouting(String address)

Method adds a new routing address for the component. Routing addresses are used by the MessageRouter to calculate packet's destination. If the packet's destination address matches one of the component's routing addresses the packet is added to the component's internal input queue.

By default all components accept packets addressed to the componentId and to:

 component.getName() + '@' + any virtual domain
 

Parameters:

address - is a Java regular expression string for the packet's destination address accepted by this component.

clearRegexRoutings

public void clearRegexRoutings()

Method clears, removes all the component routing addresses. After this method call the component accepts only packets addressed to default routings that is component ID or the component name + '@' + virtual domains

everyHour

public void everyHour()

Utility method executed precisely every hour. A component can overwrite the method to put own code to be executed at the regular intervals of time.

Note, no extensive calculations should happen in this method nor long lasting operations. It is essential that the method processing does not exceed 1 hour. The overriding method must call the the super method first and only then run own code.

everyMinute

public void everyMinute()

Utility method executed precisely every minute. A component can overwrite the method to put own code to be executed at the regular intervals of time.

Note, no extensive calculations should happen in this method nor long lasting operations. It is essential that the method processing does not exceed 1 minute. The overriding method must call the the super method first and only then run own code.

everySecond

public void everySecond()

Utility method executed precisely every second. A component can overwrite the method to put own code to be executed at the regular intervals of time.

Note, no extensive calculations should happen in this method nor long lasting operations. It is essential that the method processing does not exceed 1 second. The overriding method must call the the super method first and only then run own code.

getDefaults

public Map<String,Object> getDefaults(Map<String,Object> params)

Returns default configuration settings for the component as a Map with keys as configuration property IDs and values as the configuration property values. All the default parameters returned from this method are later passed to the setProperties(...) method. Some of them may have changed value if they have been overwritten in the server configuration. The configuration property value can be of any of the basic types: int, long, boolean, String.

Specified by:

getDefaults in interface Configurable

Overrides:

getDefaults in class BasicComponent

Parameters:

params - is a Map with some initial properties set for the starting up server. These parameters can be used as a hints to generate component's default configuration.

Returns:

a Map with the component default configuration.

getRegexRoutings

public Set<Pattern> getRegexRoutings()

Method returns a Set with all component's routings as a compiled regular expression patterns. The Set can be empty but it can not be null.

Returns:

a Set with all component's routings as a compiled regular expression patterns.

getStatistics

public void getStatistics(StatisticsList list)

Method returns component statistics. Please note, the method can be called every second by the server monitoring system therefore no extensive or lengthy calculations are allowed. If there are some statistics requiring lengthy operations like database access they must have Level.FINEST assigned and must be put inside the level guard to prevent generating them by the system monitor. The system monitor does not collect FINEST statistics.

Level guard code looks like the example below:

 if (list.checkLevel(Level.FINEST)) {
   // Some CPU intensive calculations or lengthy operations
   list.add(getName(), "Statistic description", stat_value, Level.FINEST);
 }
 
 
 This way you make sure your extensive operation is not executed every second by the
 monitoring system and does not affect the server performance.


Specified by:
getStatistics in interface StatisticsContainer


Parameters:
list - is a StatistcsList
 where all statistics are stored.

hashCodeForPacket

public int hashCodeForPacket(Packet packet)

This method decides how incoming packets are distributed among processing threads. Different components needs different distribution to efficient use all threads and avoid packets re-ordering.

If there are N processing threads, packets are distributed among threads using following code:

 int threadNo = Math.abs(hashCodeForPacket(packet) % N);
 

For a PubSub component, for example, a better packets distribution would be based on the PubSub channel name, for SM a better distribution is based on the destination address, etc....

Parameters:

packet - is a Packet which needs to be processed by some thread.

Returns:

a hash code generated for the input thread.

isInRegexRoutings

public boolean isInRegexRoutings(String address)

Method description

Specified by:

isInRegexRoutings in interface MessageReceiver

Parameters:

address -

Returns:

newPacketId

public String newPacketId(String prefix)

Method description

Parameters:

prefix -

Returns:

processPacket

public final void processPacket(Packet packet,
                                Queue<Packet> results)

Method description

Specified by:

processPacket in interface ServerComponent

Overrides:

processPacket in class BasicComponent

Parameters:

packet -

results -

processingThreads

@Deprecated
public int processingThreads()

Deprecated.

There is now a separate setting for incoming packets and outgoing packets processing. Some components are uni-directional, hence they don't even use any threads in one direction. This way you can save resources by reducing unneeded threads. Use processingOutThreads() and processingInThreads() instead.

Returns:

processingOutThreads

public int processingOutThreads()

processingInThreads

public int processingInThreads()

release

public void release()

Method description

Specified by:

release in interface ServerComponent

Overrides:

release in class BasicComponent

removeRegexRouting

public boolean removeRegexRouting(String address)

Method description

Parameters:

address -

Returns:

setMaxQueueSize

public void setMaxQueueSize(int maxQueueSize)

Method description

Parameters:

maxQueueSize -

setName

public void setName(String name)

Method description

Specified by:

setName in interface ServerComponent

Overrides:

setName in class BasicComponent

Parameters:

name -

setParent

public void setParent(MessageReceiver parent)

Method description

Specified by:

setParent in interface MessageReceiver

Parameters:

parent -

setProperties

@TODO(note="Replace fixed filers loading with configurable options for that")
public void setProperties(Map<String,Object> props)

Sets all configuration properties for object.

Specified by:

setProperties in interface Configurable

Overrides:

setProperties in class BasicComponent

Parameters:

props -

start

public void start()

Method description

Specified by:

start in interface MessageReceiver

stop

public void stop()

Method description

addOutPacket

protected boolean addOutPacket(Packet packet)

addOutPacketNB

protected boolean addOutPacketNB(Packet packet)

Non blocking version of addOutPacket.

Parameters:

packet - a Packet value

Returns:

a boolean value

addOutPacketWithTimeout

protected boolean addOutPacketWithTimeout(Packet packet,
                                          ReceiverTimeoutHandler handler,
                                          long delay,
                                          TimeUnit unit)

addOutPackets

protected boolean addOutPackets(Queue<Packet> packets)

addTimerTask

protected void addTimerTask(TimerTask task,
                            long delay,
                            TimeUnit unit)

addTimerTask

protected void addTimerTask(TimerTask task,
                            long delay)

getMaxQueueSize

protected Integer getMaxQueueSize(int def)