org.qbroker.node

Class ParserNode

java.lang.Object

org.qbroker.node.Node

org.qbroker.node.ParserNode

All Implemented Interfaces:

MessageNode

public class ParserNode
extends Node

ParserNode parses JMS Message body and extracts properties out of it. According to the rulesets, it filters messages into three outlinks: done for all the parsed messages, nohit for those messages do not belong to any rulesets, failure for the messages failed at the parsing process. Those parsed messages will have variables extracted from the body and put to the message properties for easy access.

ParserNode 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 defines the parser and its parsing rules for the group. Different groups may have different parser or different parser parameters. Due to JMS specifications, you have to clear user properties before setting user properties on a readonly message. You can specify ResetOption in a ruleset so that the message header will be reset for modifications. Its value is 0 for no reset, 1 for optional reset and 2 for absolute reset. With each ruleset, you can also specify the data to be parsed via FieldName. By default, the FieldName is set to "body", indicating to parse the message body. A ruleset can also define TimestampKey and TimePattern to reset JMSTimestamp of the messages for the group. On the node level, DisplayMask and StringProperty control the display result of outgoing messages.

ParserNode supports a post formatter defined within the filter for the parser rules. Even if the rule is a bypass one, it can also have a post formatter as long as its preferred outlink is the first outlink. In case of failure or nohit, the post formatter will be disabled.

ParserNode allows the developers to plugin their own parsers. The requirement is minimum. The class should have a public method of parse() that takes the String to be parsed as the only argument. The returned object has to be either a Map or an Event. It must have a constructor taking a Map, or a List, or just a String as the only argument for configurations. ParserNode will invoke the public method to parse the either message body or certain message property as a text.

You are free to choose any names for the three fixed outlinks. But ParserNode always assumes the first outlink for done, the second for failure and the last for nohit.

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
ParserNode(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.

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, updateParameters

Methods inherited from class java.lang.Object

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

Constructor Detail

ParserNode

public ParserNode(java.util.Map props)

Method Detail

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