org.opennms.netmgt.poller.monitors

Class AbstractServiceMonitor

java.lang.Object

org.opennms.netmgt.poller.monitors.AbstractServiceMonitor

All Implemented Interfaces:

ServiceMonitor

Direct Known Subclasses:

AsteriskSIPPeerMonitor, AvailabilityMonitor, BSFMonitor, CitrixMonitor, DhcpMonitor, DnsMonitor, DNSResolutionMonitor, DominoIIOPMonitor, EndPointMonitor, FtpMonitor, GpMonitor, HttpMonitor, HttpPostMonitor, IcmpMonitor, ImapMonitor, JCifsMonitor, JDBCMonitor, JMXMonitor, JolokiaBeanMonitor, JschSshMonitor, LdapMonitor, MailTransportMonitor, MemcachedMonitor, NrpeMonitor, NsclientMonitor, NtpMonitor, PageSequenceMonitor, Pop3Monitor, RadiusAuthMonitor, SeleniumMonitor, SmbMonitor, SmtpMonitor, SnmpMonitorStrategy, SshMonitor, SSLCertMonitor, StrafePingMonitor, SystemExecuteMonitor, TcpMonitor, TrivialTimeMonitor, VmwareCimMonitor, VmwareMonitor, WebMonitor, WmiMonitor, XmpMonitor

public abstract class AbstractServiceMonitor
extends Object
implements ServiceMonitor

This class provides a basic implementation for most of the interface methods of the ServiceMonitor class. Since most pollers do not do any special initialization, and only require that the interface is an InetAddress object this class provides everything by the poll interface.

Author:

Mike, Weave, OpenNMS

Constructor Summary

Constructors

Constructor and Description
AbstractServiceMonitor()

Method Summary

Methods

Modifier and Type	Method and Description
static Boolean	getKeyedBoolean(Map<String,Object> parameterMap, String key, Boolean defaultValue)
static Integer	getKeyedInteger(Map<String,Object> parameterMap, String key, Integer defaultValue)
static Long	getKeyedLong(Map<String,Object> parameterMap, String key, Long defaultValue)
static Object	getKeyedObject(Map<String,Object> parameterMap, String key, Object defaultValue)
static String	getKeyedString(Map<String,Object> parameterMap, String key, String defaultValue)
void	initialize(Map<String,Object> parameters) This method is called after the framework creates an instance of the plug-in.
void	initialize(MonitoredService svc) This method is called whenever a new interface that supports the plug-in service is added to the scheduling system.
abstract PollStatus	poll(MonitoredService svc, Map<String,Object> parameters) This method is the heart of the plug-in monitor.
void	release() This method is called whenever the plug-in is being unloaded, normally during framework exit.
void	release(MonitoredService svc) This method is the called whenever an interface is being removed from the scheduler.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractServiceMonitor

public AbstractServiceMonitor()

Method Detail

initialize

public void initialize(Map<String,Object> parameters)

This method is called after the framework creates an instance of the plug-in. The framework passes the object a proxy object that can be used to retrieve configuration information specific to the plug-in. Additionally, any parameters for the plug-in from the package definition are passed using the parameters element.

If there is a critical error, like missing service libraries, the the Monitor may throw a ServiceMonitorException. If the plug-in throws an exception then the plug-in will be disabled in the framework.

This method is called after the framework creates an instance of the plug-in. The framework passes the object a proxy object that can be used to retrieve configuration information specific to the plug-in. Additionally, any parameters for the plug-in from the package definition are passed using the parameters element.

If there is a critical error, like missing service libraries, the monitor may throw a ServiceMonitorException. If the plug-in throws an exception then the plug-in will be disabled in the framework.

Specified by:

initialize in interface ServiceMonitor

Parameters:

parameters - Not currently used

Throws:

RuntimeException - Thrown if an unrecoverable error occurs that prevents the plug-in from functioning.

release

public void release()

This method is called whenever the plug-in is being unloaded, normally during framework exit. During this time the framework may release any resource and save any state information using the proxy object from the initialization routine.

Even if the plug-in throws a monitor exception, it will not prevent the plug-in from being unloaded. The plug-in should not return until all of its state information is saved. Once the plug-in returns from this call its configuration proxy object is considered invalid.

Specified by:

release in interface ServiceMonitor

Throws:

RuntimeException - Thrown if an error occurs during deallocation.

initialize

public void initialize(MonitoredService svc)

This method is called whenever a new interface that supports the plug-in service is added to the scheduling system. The plug-in has the option to load and/or associate configuration information with the interface before the framework begins scheduling the new device.

Should a monitor exception be thrown during an initialization call then the framework will log an error and discard the interface from scheduling.

Specified by:

initialize in interface ServiceMonitor

Parameters:

svc - a MonitoredService object.

Throws:

RuntimeException - Thrown if an unrecoverable error occurs that prevents the interface from being monitored.

release

public void release(MonitoredService svc)

This method is the called whenever an interface is being removed from the scheduler. For example, if a service is determined as being no longer supported then this method will be invoked to cleanup any information associated with this device. This gives the implementor of the interface the ability to serialize any data prior to the interface being discarded.

If an exception is thrown during the release the exception will be logged, but the interface will still be discarded for garbage collection.

This method is the called whenever an interface is being removed from the scheduler. For example, if a service is determined as being no longer supported then this method will be invoked to cleanup any information associated with this device. This gives the implementor of the interface the ability to serialize any data prior to the interface being discarded.

If an exception is thrown during the release the exception will be logged, but the interface will still be discarded for garbage collection.

Specified by:

release in interface ServiceMonitor

Parameters:

svc - TODO

Throws:

RuntimeException - Thrown if an unrecoverable error occurs that prevents the interface from being monitored.

poll

public abstract PollStatus poll(MonitoredService svc,
              Map<String,Object> parameters)

This method is the heart of the plug-in monitor. Each time an interface requires a check to be performed as defined by the scheduler the poll method is invoked. The poll is passed the interface to check

By default when the status transition from up to down or vice versa the framework will generate an event. Additionally, if the polling interval changes due to an extended unavailability, the framework will generate an additional down event. The plug-in can suppress the generation of the default events by setting the suppress event bit in the returned integer.

Specified by:

poll in interface ServiceMonitor

Parameters:

svc - TODO

parameters - The package parameters (timeout, retry, etc...) to be used for this poll.

Returns:

The availability of the interface and if a transition event should be suppressed.

See Also:

PollStatus.SERVICE_AVAILABLE, PollStatus.SERVICE_UNAVAILABLE, PollStatus.SERVICE_AVAILABLE, PollStatus.SERVICE_UNAVAILABLE

getKeyedObject

public static Object getKeyedObject(Map<String,Object> parameterMap,
                    String key,
                    Object defaultValue)

getKeyedBoolean

public static Boolean getKeyedBoolean(Map<String,Object> parameterMap,
                      String key,
                      Boolean defaultValue)

getKeyedString

public static String getKeyedString(Map<String,Object> parameterMap,
                    String key,
                    String defaultValue)

getKeyedInteger

public static Integer getKeyedInteger(Map<String,Object> parameterMap,
                      String key,
                      Integer defaultValue)

getKeyedLong

public static Long getKeyedLong(Map<String,Object> parameterMap,
                String key,
                Long defaultValue)