org.qbroker.node

Class RequestNode

java.lang.Object

org.qbroker.node.Node

org.qbroker.node.RequestNode

All Implemented Interfaces:

MessageNode

public class RequestNode
extends Node

RequestNode picks up JMS messages as requests or their async responses from the uplink and processes them according to their content and the pre-defined rulesets. There are four fixed outlinks, done, bypass, failure, and nohit, as well as the request outlink for collectiables. For a request message, RequestNode routes it to the request outlink first. Once the message is collected from the outlink, it will be cached with a unique key waiting for the asynchonous reply. When a response message finally arrives, RequestNode extracts the unique key from it and looks for the corresponding request message from the cache. If the request message is found, RequestNode loads the response to the request message and routes it to the outlink of done. The response message will be routed to the outlink of bypass afterwards. This is called that the request message has been claimed by its response. If there is no corresponding request found for the response message, it will be routed to the outlink of nohit. In case that a cached key has expired, its request message will be flushed to the outlink of failure. Eventually, all the claimed keys or expired keys will be removed from the cache. If an incoming message is neither a request nor a response, RequestNode will treat it as a bypass and routes it to one of the four fixed outlinks without any delay. Since RequestNode does not consume any message, any incoming message has to find a way out via one of the four fixed outlinks.

RequestNode contains a number of pre-defined rulesets. These rulesets categorize messages into non-overlapping groups. Therefore, each rule defines a unique message group. The ruleset also defines the cache or claim options for the messages in each group as well as the other parameters used in the process. Furthermore, RequestNode always creates one extra ruleset, nohit. The ruleset of nohit is for all the messages not hitting any of the filters.

You are free to choose any names for the first four fixed outlinks. But RequestNodee always assumes the first outlink for done, the second for bypass, the third for failure and the fourth for nohit. The rest of the outlinks are for collectibles. It is OK for those first four fixed outlinks to share the same name. Please make sure the first fixed outlink has the actual capacity no less than that of the uplink.

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
RequestNode(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 int	feedback(XQueue in, long milliSec) It returns the number of done messages removed from the input XQueue.
protected void	finalize()
int	getOutLinkBoundary() returns the BOUNDARY which is the lowest id of outlinks for collectibles so that any outlink with either the same id or a higher id is for collectibles.
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.
java.util.Map<java.lang.String,java.lang.String>	listPendings(XQueue xq, int type) lists all propagating and cached messages
protected int	passthru(long currentTime, javax.jms.Message msg, XQueue in, int rid, int oid, int cid, int tid) It passes the message from the input XQueue over to an output XQueue and returns 1 upon success or 0 otherwise.
void	propagate(XQueue in, XQueue[] out) It picks up messages from the input XQueue and evaluates their content to decide which output XQueues to propagate.
void	resetMetaData(XQueue in, XQueue[] out) cleans up MetaData for all XQs and messages
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, forcethru, getCapacity, getCapacity, getDebugMode, getDisplayMask, getDisplayProperties, getLinkName, getLinkName, getMetaData, getName, getNumberOfOutLinks, getNumberOfRules, getOperation, getRuleName, getStatus, getXAMode, getXAMode, internalXQSupported, list, refreshRule, removeRule, renameRule, replaceRule, 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

RequestNode

public RequestNode(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

propagate

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

Description copied from class: Node

It picks up messages from the input XQueue and evaluates their content to decide which output XQueues to propagate.

Specified by:

propagate in interface MessageNode

Specified by:

propagate in class Node

Throws:

javax.jms.JMSException

passthru

protected int passthru(long currentTime,
                       javax.jms.Message msg,
                       XQueue in,
                       int rid,
                       int oid,
                       int cid,
                       int tid)

It passes the message from the input XQueue over to an output XQueue and returns 1 upon success or 0 otherwise. If tid is less than 0, msg will not be put back to uplink in case of failure.

Overrides:

passthru in class Node

feedback

protected int feedback(XQueue in,
                       long milliSec)

It returns the number of done messages removed from the input XQueue. If milliSec is less than 0, there is no wait and it tries to collect all cells. Otherwise, it just tries to collect the first collectible cell.

Overrides:

feedback in class Node

resetMetaData

public void resetMetaData(XQueue in,
                          XQueue[] out)

cleans up MetaData for all XQs and messages

Specified by:

resetMetaData in interface MessageNode

Overrides:

resetMetaData in class Node

listPendings

public java.util.Map<java.lang.String,java.lang.String> listPendings(XQueue xq,
                                                                     int type)

lists all propagating and cached messages

Specified by:

listPendings in interface MessageNode

Overrides:

listPendings in class Node

getOutLinkBoundary

public int getOutLinkBoundary()

returns the BOUNDARY which is the lowest id of outlinks for collectibles so that any outlink with either the same id or a higher id is for collectibles. The EXTERNAL_XA bit of all outlinks for collectibles has to be disabled by the container to stop ack propagations downsstream.

Specified by:

getOutLinkBoundary in interface MessageNode

Overrides:

getOutLinkBoundary in class Node

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