org.qbroker.monitor

Class PropertyMonitor

java.lang.Object

org.qbroker.monitor.Monitor

org.qbroker.monitor.PropertyMonitor

All Implemented Interfaces:

MonitorAction, MonitorReport

public class PropertyMonitor
extends Monitor

PropertyMonitor monitors a given set of properties on their last modified time and content. If its mtime is newer, it will load the content and converts it into a property map and stores it to the report. The action part will compare the new property to the existing property to get changes. If there is any change, the map with changes will replace the new property map in the report. Meanwhile, if PropertyFile is defined, it will also update the local files. If there is no change at all, the value of the new property map stored in the report will be reset to null to indicate no change.

Use PropertyMonitor to get the update time of a given set of properties. The properties can be stored in a file, a web page or a database table. It is assumed there is a timestamp for each set of properties. If the timestamp is newer, the downloaded property map will be stored in the report with the key of "Property".

You can use it to monitor changes on properties of an application. If the properties have been updated, performAction() will compare the new set of properties to the existing ones and returns the change map via the latest report map under the key of "Property". The change map is a map with only modified or new properties. The deleted item will have null as the value. If there is no change, it will be set to null. Otherwise, you can retrieve the change map from the report. With this property map, you can reload the objects directly.

PropertyMonitor is able to include properties defined outside the master file. IncludeGroup is a map specifying all the components to be loaded from outside of the master file. It supports three scenarios:
LIST/LIST: {"MonitorGroup": ["Monitor"]}
LIST: {"Flow": ["Reporter"]}
MAP: {"ConfigRepository":""}
where Flow is the name of the master property file.

PropertyMonitor also supports secondary includes on certain type of primary included components. It means those components may contain listed objects defined outside of their configuration files. SecondaryInclude is a map specifying what lists of primary includes may contain secondary includes. Any key of SecondaryInclude has to be one of the values of IncludeGroup. For example:
{"Node": "IncludePolicy"}
where Node is the name of the list with primary includes. IncludePolicy is the name of the map specifying what classnames of Node may have secondary includes in their lists specified by the values. For example:
{"org.qbroker.node.EventMonitor": "Ruleset"}
where Ruleset is the name of the list that may contain secondary includes. IncludePolicy should be defined in the master configuration for that Node object.

If DataField is defined, PropertyMonitor will use it to retrieve a list from the property map. Then those objects not referenced by the list will be removed for the support of projections.

Currently, it only supports web based or local JSON properties. Since it is always instantiated before the static reports, it can not use any of the global variables defined in the static reports. However, it does support the special variables loaded from a set of environment variables. But they are limited to URI and authentication stuff. Those environment variables have the higher precedence over the inline properties.

Author:

yannanlu@yahoo.com

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	FILE_SEPARATOR

Fields inherited from class org.qbroker.monitor.Monitor

actionCount, actionGroup, aPatternGroup, cachedSkip, category, dependencyGroup, description, disabledWithReport, disableMode, exceptionCount, exceptionTolerance, formatText, keyList, maxPage, maxRetry, name, normalStep, pm, previousStatus, repeatPeriod, report, reportMode, reportName, resolution, serialNumber, site, skip, statsLogger, statusOffset, statusText, step, template, timeFormat, timeTemplate, tolerance, type, xPatternGroup

Fields inherited from interface org.qbroker.monitor.MonitorReport

DISABLED, EXCEPTION, NOSKIP, REPORT_CACHED, REPORT_CLUSTER, REPORT_FINAL, REPORT_FLOW, REPORT_LOCAL, REPORT_NODE, REPORT_NONE, REPORT_SHARED, SKIPPED

Constructor Summary

Constructors

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

Method Summary

Modifier and Type	Method and Description
java.util.Map<java.lang.String,java.lang.Object>	checkpoint() returns the checkpoint Map for the action
void	destroy() closes and releases all opened resources
protected void	finalize()
java.util.Map<java.lang.String,java.lang.Object>	generateReport(long currentTime) generates a report on a monitored entity and returns it as a Map.
int	getDebugMode()
java.util.Map<java.lang.String,java.lang.Object>	getIncludeMap() returns the full clone of includeGroup for includes
static void	main(java.lang.String[] args) It builds the complete JSON property file according to the master configuration file and the files for individual components.
Event	performAction(int status, long currentTime, java.util.Map<java.lang.String,java.lang.Object> latest) examines the report on the monitored entity and reacts to it as an action
void	restoreFromCheckpoint(java.util.Map<java.lang.String,java.lang.Object> chkpt) restores the state of the action from the checkpoint Map
void	setDataField(java.lang.String key) sets the dataField for projection support
void	setDebugMode(int debug)
void	setOriginalProperty(java.util.Map props)

Methods inherited from class org.qbroker.monitor.Monitor

getName, getReportKeys, getReportMode, getReportName, getSkippingStatus, initTimeTemplate, updateContent

Methods inherited from class java.lang.Object

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

Field Detail

FILE_SEPARATOR

public static final java.lang.String FILE_SEPARATOR

Constructor Detail

PropertyMonitor

public PropertyMonitor(java.util.Map props)

Method Detail

generateReport

public java.util.Map<java.lang.String,java.lang.Object> generateReport(long currentTime)
                                                                throws java.io.IOException

Description copied from interface: MonitorReport

generates a report on a monitored entity and returns it as a Map. The report Map will be passed to the associated MonitorAction as an opaque object. The action object is supposed to know how to retrieve the information from the report Map.

Specified by:

generateReport in interface MonitorReport

Specified by:

generateReport in class Monitor

Throws:

java.io.IOException

performAction

public Event performAction(int status,
                           long currentTime,
                           java.util.Map<java.lang.String,java.lang.Object> latest)

Description copied from interface: MonitorAction

examines the report on the monitored entity and reacts to it as an action

Specified by:

performAction in interface MonitorAction

Specified by:

performAction in class Monitor

setDebugMode

public void setDebugMode(int debug)

getDebugMode

public int getDebugMode()

setDataField

public void setDataField(java.lang.String key)

sets the dataField for projection support

setOriginalProperty

public void setOriginalProperty(java.util.Map props)

getIncludeMap

public java.util.Map<java.lang.String,java.lang.Object> getIncludeMap()

returns the full clone of includeGroup for includes

checkpoint

public java.util.Map<java.lang.String,java.lang.Object> checkpoint()

Description copied from interface: MonitorAction

returns the checkpoint Map for the action

Specified by:

checkpoint in interface MonitorAction

Overrides:

checkpoint in class Monitor

restoreFromCheckpoint

public void restoreFromCheckpoint(java.util.Map<java.lang.String,java.lang.Object> chkpt)

Description copied from interface: MonitorAction

restores the state of the action from the checkpoint Map

Specified by:

restoreFromCheckpoint in interface MonitorAction

Overrides:

restoreFromCheckpoint in class Monitor

destroy

public void destroy()

Description copied from interface: MonitorReport

closes and releases all opened resources

Specified by:

destroy in interface MonitorReport

Overrides:

destroy in class Monitor

finalize

protected void finalize()

Overrides:

finalize in class Monitor

main

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

It builds the complete JSON property file according to the master configuration file and the files for individual components. The configuration parameters are stored in the json file, pm.json, that defines how to handle all applications, etc.

Usage: java PropertyMonitor [-?|-l|-I configFile|...]