//
// This file is part of the OpenNMS(R) Application.
//
// OpenNMS(R) is Copyright (C) 2002-2003 The OpenNMS Group, Inc. All rights reserved.
// OpenNMS(R) is a derivative work, containing both original code, included code and modified
// code that was published under the GNU General Public License. Copyrights for modified
// and included code are below.
//
// OpenNMS(R) is a registered trademark of The OpenNMS Group, Inc.
//
// Modifications:
//
// 2003 Jan 31: Added the ability to imbed RRA information in poller packages.
//
// Original code base Copyright (C) 1999-2001 Oculan Corp. All rights reserved.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
//
// For more information contact:
// OpenNMS Licensing <license@opennms.org>
// http://www.opennms.org/
// http://www.opennms.com/
//
package org.infosec.ismp.model.poller;
import java.util.Map;
/**
* <p>
* This is the interface that must be implemented by each poller plugin in the
* framework. This well defined interface allows the framework to treat each
* plugin identically.
* </p>
*
* <p>
* When a service monitor plug-in is loaded and initialized, the framework will
* initialize the monitor by calling the <EM>initialize()</EM> method.
* Likewise, when the monitor is unloaded the framework calls the <EM>release()
* </EM> method is called. If the plug-in needs to save or read any
* configuration information after the initialize() call, a reference to the
* proxy object should be saved at initialization.
* </p>
*
* <P>
* <STRONG>NOTE: </STRONG> The plug-in <EM>poll()</EM> must be thread safe in
* order to operate. Any synchronized methods or data accessed in the <EM>
* poll()</EM> can negatively affect the framework if multiple poller threads
* are blocked on a critical resource. Synchronization issues should be
* seriously evaluated to ensure that the plug-in scales well to large
* deployments.
* </P>
*
* @author <A HREF="mailto:weave@oculan.com">Brian Weaver </A>
* @author <A HREF="http://www.opennms.org/">OpenNMS </A>
*
*/
public interface ServiceMonitor {
/**
* <P>
* 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.
* </P>
*
* <P>
* 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.
* </P>
* @param parameters
* Not currently used
*
* @exception java.lang.RuntimeException
* Thrown if an unrecoverable error occurs that prevents the
* plug-in from functioning.
*
*/
public void initialize(Map<String, Object> parameters);
/**
* <P>
* 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.
* </P>
*
* <P>
* 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.
* </P>
*
* @exception java.lang.RuntimeException
* Thrown if an error occurs during deallocation.
*
*/
public void release();
/**
* <P>
* 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.
* </P>
*
* <P>
* Should a monitor exception be thrown during an initialization call then
* the framework will log an error and discard the interface from
* scheduling.
* </P>
* @param svc TODO
*
* @exception java.lang.RuntimeException
* Thrown if an unrecoverable error occurs that prevents the
* interface from being monitored.
* @exception
* org.opennms.netmgt.poller.NetworkInterfaceNotSupportedException
* Thrown if the passed interface is invalid for this
* monitor.
*
*/
public void initialize(MonitoredService svc);
/**
* <P>
* 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.
* </P>
*
* <P>
* If an exception is thrown during the release the exception will be
* logged, but the interface will still be discarded for garbage collection.
* </P>
* @param svc TODO
*
* @exception java.lang.RuntimeException
* Thrown if an unrecoverable error occurs that prevents the
* interface from being monitored.
*/
public void release(MonitoredService svc);
/**
* <P>
* 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
* </P>
*
* <P>
* 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.
* </P>
* @param svc TODO
* @param parameters
* The package parameters (timeout, retry, etc...) to be used for
* this poll.
* @return The availability of the interface and if a transition event
* should be suppressed.
*
* @exception java.lang.RuntimeException
* Thrown if an unrecoverable error occurs that prevents the
* interface from being monitored.
*
* @see PollStatus#SERVICE_AVAILABLE
* @see PollStatus#SERVICE_UNAVAILABLE
*/
public PollStatus poll(MonitoredService svc, Map<String, Object> parameters);
}