org.jgroups.protocols.rules
Class Rule

java.lang.Object
  org.jgroups.protocols.rules.Rule

All Implemented Interfaces:

java.lang.Runnable

Direct Known Subclasses:

CheckFDMonitor, SampleRule

public abstract class Rule
extends java.lang.Object
implements java.lang.Runnable

A rule with a condition and (optional) action. When a rule is run, the condition is checked with eval() and - if true - the action is triggered with trigger().

Since:

3.3

Author:

Bela Ban

Field Summary

protected Log	log
protected SUPERVISOR	sv

Constructor Summary

Rule()

Method Summary

abstract java.lang.String	condition() Returns a description of the condition that led to eval() returning true
abstract java.lang.String	description() Describes what the rules does
void	destroy() Called when rule is uninstalled
abstract boolean	eval() Evaluates the condition.
void	init() Called when rule is installed
Rule	log(Log log)
abstract java.lang.String	name() Returns the name of the rule.
void	run()
Rule	supervisor(SUPERVISOR sv)
abstract void	trigger() The action of the rule.

Methods inherited from class java.lang.Object

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

Field Detail

sv

protected SUPERVISOR sv

log

protected Log log

Constructor Detail

Rule

public Rule()

Method Detail

supervisor

public Rule supervisor(SUPERVISOR sv)

log

public Rule log(Log log)

name

public abstract java.lang.String name()

Returns the name of the rule. Should be unique if a rule needs to be uninstalled

description

public abstract java.lang.String description()

Describes what the rules does

init

public void init()

Called when rule is installed

destroy

public void destroy()

Called when rule is uninstalled

eval

public abstract boolean eval()

Evaluates the condition. If true, the rule is triggered. If true, the next execution of condition() should return a non-null string

condition

public abstract java.lang.String condition()

Returns a description of the condition that led to eval() returning true

trigger

public abstract void trigger()
                      throws java.lang.Throwable

The action of the rule. Triggered if eval() returned true

Throws:

java.lang.Throwable

run

public void run()

Specified by:

run in interface java.lang.Runnable