org.qbroker.node

Class SwitchNode

java.lang.Object

org.qbroker.node.Node

org.qbroker.node.SwitchNode

All Implemented Interfaces:

MessageNode

public class SwitchNode
extends Node

SwitchNode switches JMS messages to various destinations according to their content, and preconfigured rulesets. SwitchNode contains a number of predefined rulesets. These rulesets categorize messages into non-overlapping groups. Therefore, each rule defines a unique message group. The ruleset also specifies the association between the groups and the outlinks. A ruleset can be also assosiated to a shared report. So that the routing rules may be changed on the fly.

SwitchNode always adds an extra ruleset for the nohit messages. It assumes the last outlink is always for nohit, unless NohitOutLink is defined. A ruleset is supposed to specify the type of the ruleset. Currently, SwitchNode supports 3 types, preferred, sticky and weighted. The type of preferred routes the messages to the preferred outlink. The type of sticky is also a static routing rule which uses the hash value to decide which outlink to route. The type of weighted is for dynamic routing with plugin support.

SwitchNode also allows the developers to plug-in their own dynamic routing rules. In this case, the full ClassName of the router and its RouterArguments must be well defined in the rulesets. The requirement on the plug-ins is minimum. The class must have a public method of route(Message msg) that takes JMS Message as the only argument. The return object must be an Integer for the id of the route. In any case, it should never acknowledge any messages. It must also have a constructor taking a Map, or a List, or just a String as the only argument for the configurations. SwitchNode will invoke the public method to get the route id for each incoming messages. You can define PreferredOutLink in the Ruleset as the default outlink for failures. Otherwise, the default outlink will be set to NOHIT.

In case a plugin needs to connect to external resources for dynamic routing process, it should define an extra method of close() to close all the external resources gracefully. Its route method should also be able to detect the disconnections and cleanly reconnect to the resources automatically. If the container wants to stop the node, it will invoke resetMetaData() in which the method of close() of all dynamic routers will be invoked in order to release all external resources.

Author:

yannanlu@yahoo.com

Field Summary

Fields inherited from class org.qbroker.node.Node

assetList, bufferSize, callbackMethod, capacity, cbw, cells, cfgList, chkptExpiration, debug, DEBUG_COLL, DEBUG_DIFF, DEBUG_FBAK, DEBUG_INIT, DEBUG_PASS, DEBUG_PROP, DEBUG_REPT, DEBUG_UPDT, displayMask, displayPropertyName, linkName, LOAD_HIGH, LOAD_LOW, LOAD_MEDIUM, msgList, name, operation, RESET_ALL, RESET_MAP, RESET_NONE, RESET_SOME, ruleList, status, TYPE_ACTION, TYPE_AGGREGATE, TYPE_BYPASS, TYPE_CACHE, TYPE_COLLECT, TYPE_DELIVER, TYPE_FORMAT, TYPE_JSONPATH, TYPE_JSONT, TYPE_MAPREDUCE, TYPE_NONE, TYPE_PARSER, TYPE_PICKUP, TYPE_PIPE, TYPE_PUBLISH, TYPE_ROUNDROBIN, TYPE_SCREEN, TYPE_SCRIPT, TYPE_SERVICE, TYPE_SORT, TYPE_SPLIT, TYPE_SPREAD, TYPE_WEIGHTED, TYPE_XPATH, TYPE_XSLT, waitTime, xaMode

Fields inherited from interface org.qbroker.node.MessageNode

ASSET_THR, ASSET_URI, ASSET_XQ, META_MAP, META_MSG, META_OUT, META_RULE, META_XQ, MSG_BID, MSG_CID, MSG_OID, MSG_RID, MSG_TID, MSG_TIME, NODE_CLOSED, NODE_DISABLED, NODE_PAUSE, NODE_READY, NODE_RETRYING, NODE_RUNNING, NODE_STANDBY, NODE_STOPPED, OUT_CAPACITY, OUT_COUNT, OUT_DEQ, OUT_EXTRA, OUT_LENGTH, OUT_MODE, OUT_NRULE, OUT_OFFSET, OUT_ORULE, OUT_QDEPTH, OUT_QIPPS, OUT_QSTATUS, OUT_QTIME, OUT_SIZE, OUT_STATUS, OUT_TIME, RULE_COUNT, RULE_DMASK, RULE_EXTRA, RULE_GID, RULE_MODE, RULE_OID, RULE_OPTION, RULE_PEND, RULE_PID, RULE_SIZE, RULE_STATUS, RULE_TIME, RULE_TTL

Constructor Summary

Constructors

Constructor and Description
SwitchNode(java.util.Map props)

Method Summary

Modifier and Type	Method and Description
void	close() It closes all resources and cleans up all list, cache, metadata, etc.
protected void	finalize()
protected java.util.Map<java.lang.String,java.lang.Object>	initRuleset(long tm, java.util.Map ph, long[] ruleInfo) It initializes a new ruleset with the ruleInfo and returns the rule upon success.
void	propagate(XQueue in, XQueue[] out) picks up a message from input queue and evaluate its content to decide which output queue to propagate
int	removeRule(java.lang.String key, XQueue in) It removes the rule from the ruleList and returns the rule id upon success.
int	replaceRule(java.lang.String key, java.util.Map ph, XQueue in) It replaces the existing rule of the key and returns its id upon success.
int	updateParameters(java.util.Map props) It updates the parameters of the node with the given property map.

Methods inherited from class org.qbroker.node.Node

addRule, callback, checkpoint, collectAll, containsRule, containsXQ, feedback, forcethru, getCapacity, getCapacity, getDebugMode, getDisplayMask, getDisplayProperties, getLinkName, getLinkName, getMetaData, getName, getNumberOfOutLinks, getNumberOfRules, getOperation, getOutLinkBoundary, getRuleName, getStatus, getXAMode, getXAMode, internalXQSupported, list, listPendings, passthru, refreshRule, renameRule, resetMetaData, restore, rotateRule, setDebugMode, setDisplayMask, setDisplayProperties, setStatus, show, takeback, takebackEnabled

Methods inherited from class java.lang.Object

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

Constructor Detail

SwitchNode

public SwitchNode(java.util.Map props)

Method Detail

updateParameters

public int updateParameters(java.util.Map props)

Description copied from class: Node

It updates the parameters of the node with the given property map. Upon success, it returns the number of parameters modified. It is not MT-Safe.

Specified by:

updateParameters in interface MessageNode

Overrides:

updateParameters in class Node

initRuleset

protected java.util.Map<java.lang.String,java.lang.Object> initRuleset(long tm,
                                                                       java.util.Map ph,
                                                                       long[] ruleInfo)

It initializes a new ruleset with the ruleInfo and returns the rule upon success. Otherwise, it throws an exception or returns null.

Specified by:

initRuleset in class Node

removeRule

public int removeRule(java.lang.String key,
                      XQueue in)

It removes the rule from the ruleList and returns the rule id upon success. It is not MT-Safe.

Specified by:

removeRule in interface MessageNode

Overrides:

removeRule in class Node

replaceRule

public int replaceRule(java.lang.String key,
                       java.util.Map ph,
                       XQueue in)

It replaces the existing rule of the key and returns its id upon success. It is not MT-Safe.

Specified by:

replaceRule in interface MessageNode

Overrides:

replaceRule in class Node

propagate

public void propagate(XQueue in,
                      XQueue[] out)
               throws javax.jms.JMSException

picks up a message from input queue and evaluate its content to decide which output queue to propagate

Specified by:

propagate in interface MessageNode

Specified by:

propagate in class Node

Throws:

javax.jms.JMSException

close

public void close()

Description copied from class: Node

It closes all resources and cleans up all list, cache, metadata, etc. Once it is closed, it can not be used any more.

Specified by:

close in interface MessageNode

Overrides:

close in class Node

finalize

protected void finalize()

Overrides:

finalize in class Node