Class AbstractCommandHandler<R extends org.jolokia.server.core.request.JolokiaRequest>

java.lang.Object

org.jolokia.service.jmx.handler.AbstractCommandHandler<R>

All Implemented Interfaces:

CommandHandler<R>

Direct Known Subclasses:

ExecHandler, ListHandler, NotificationHandler, ReadHandler, SearchHandler, WriteHandler

public abstract class AbstractCommandHandler<R extends org.jolokia.server.core.request.JolokiaRequest>
extends Object
implements CommandHandler<R>

A handler for dealing with a certain Jolokia command

Since:

Jun 12, 2009

Author:

roland

Field Summary

Fields

Modifier and Type	Field	Description
protected org.jolokia.server.core.service.api.JolokiaContext	context
protected String	pProvider

Constructor Summary

Constructors

Constructor	Description
AbstractCommandHandler()

Method Summary

Modifier and Type	Method	Description
protected void	checkForModifiedSince(org.jolokia.server.core.util.jmx.MBeanServerAccess pServerManager, org.jolokia.server.core.request.JolokiaRequest pRequest)	Check, whether the set of MBeans for any managed MBeanServer has been change since the timestamp provided in the given request
protected abstract void	checkForRestriction(R pRequest)	Check whether there is a restriction on the type to apply.
protected void	checkType()	Check whether a command of the given type is allowed
void	destroy()	Lifecycle method called when agent goes down.
protected Object	doHandleAllServerRequest(org.jolokia.server.core.util.jmx.MBeanServerAccess serverManager, R request, Object pPreviousResult)	Default implementation fo handling a request for multiple servers at once.
protected abstract Object	doHandleSingleServerRequest(MBeanServerConnection server, R request)	Abstract method to be subclassed by a concrete handler for performing the request.
Object	handleAllServerRequest(org.jolokia.server.core.util.jmx.MBeanServerAccess pServerManager, R pRequest, Object pPreviousResult)	Override this if you want to have all servers at once for processing the request (like need for merging info as for a list command).
boolean	handleAllServersAtOnce(R pRequest)	Override this if you want all servers as list in the argument, e.g.
Object	handleSingleServerRequest(MBeanServerConnection pServer, R pRequest)	Handle a request for a single server and throw an InstanceNotFoundException if the request cannot be handle by the provided server.
void	init(org.jolokia.server.core.service.api.JolokiaContext pContext, String pProvider)	Lifecycle method in order to initialize the handler
protected boolean	isObjectNameHidden(ObjectName name)	Checks whether an ObjectName should be removed (filtered out) from results of list or search operations.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.jolokia.service.jmx.api.CommandHandler

getType

Field Details

context

protected org.jolokia.server.core.service.api.JolokiaContext context

pProvider

protected String pProvider

Constructor Details

AbstractCommandHandler

public AbstractCommandHandler()

Method Details

init

public void init(org.jolokia.server.core.service.api.JolokiaContext pContext,
 String pProvider)

Description copied from interface: CommandHandler

Lifecycle method in order to initialize the handler

Specified by:

init in interface CommandHandler<R extends org.jolokia.server.core.request.JolokiaRequest>

Parameters:

pContext - the jolokia context

pProvider - provider to use for returned names. Handlers can use this for returning meta data with the proper provider prefixed.

handleAllServersAtOnce

public boolean handleAllServersAtOnce(R pRequest)

Override this if you want all servers as list in the argument, e.g. to query each server on your own. By default, dispatching of the servers are done for you

Specified by:

handleAllServersAtOnce in interface CommandHandler<R extends org.jolokia.server.core.request.JolokiaRequest>

Parameters:

pRequest - request to decide on whether to handle all request at once

Returns:

whether you want to have CommandHandler.handleSingleServerRequest(MBeanServerConnection, JolokiaRequest) (false) or CommandHandler.handleAllServerRequest(MBeanServerAccess, JolokiaRequest, Object) (true) called.

handleSingleServerRequest

public Object handleSingleServerRequest(MBeanServerConnection pServer,
 R pRequest)
                                 throws InstanceNotFoundException,
AttributeNotFoundException,
ReflectionException,
MBeanException,
IOException,
org.jolokia.server.core.request.NotChangedException,
org.jolokia.server.core.request.EmptyResponseException

Handle a request for a single server and throw an InstanceNotFoundException if the request cannot be handle by the provided server. Does a check for restrictions as well

Specified by:

handleSingleServerRequest in interface CommandHandler<R extends org.jolokia.server.core.request.JolokiaRequest>

Parameters:

pServer - server to try

pRequest - request to process

Returns:

the object result from the request

Throws:

InstanceNotFoundException - if the provided server cant handle the request

AttributeNotFoundException

ReflectionException

MBeanException

IOException

org.jolokia.server.core.request.NotChangedException

org.jolokia.server.core.request.EmptyResponseException

handleAllServerRequest

public Object handleAllServerRequest(org.jolokia.server.core.util.jmx.MBeanServerAccess pServerManager,
 R pRequest,
 Object pPreviousResult)
                              throws ReflectionException,
InstanceNotFoundException,
MBeanException,
AttributeNotFoundException,
IOException,
org.jolokia.server.core.request.NotChangedException,
org.jolokia.server.core.request.EmptyResponseException

Override this if you want to have all servers at once for processing the request (like need for merging info as for a list command). This method is only called when CommandHandler.handleAllServersAtOnce(JolokiaRequest) returns true

Specified by:

handleAllServerRequest in interface CommandHandler<R extends org.jolokia.server.core.request.JolokiaRequest>

Parameters:

pServerManager - server manager holding all MBeans servers detected

pRequest - request to process

pPreviousResult - a previous result which for merging requests can be used to merge files

Returns:

the object found

Throws:

ReflectionException

InstanceNotFoundException

MBeanException

AttributeNotFoundException

IOException

org.jolokia.server.core.request.NotChangedException

org.jolokia.server.core.request.EmptyResponseException

checkForRestriction

protected abstract void checkForRestriction(R pRequest)

Check whether there is a restriction on the type to apply. This method should be overwritten by specific handlers if they support a more sophisticated check than only for the type

Parameters:

pRequest - request to check

checkType

protected void checkType()

Check whether a command of the given type is allowed

isObjectNameHidden

protected boolean isObjectNameHidden(ObjectName name)

Checks whether an ObjectName should be removed (filtered out) from results of list or search operations.

Parameters:

name -

Returns:

doHandleSingleServerRequest

protected abstract Object doHandleSingleServerRequest(MBeanServerConnection server,
 R request)
                                               throws InstanceNotFoundException,
AttributeNotFoundException,
ReflectionException,
MBeanException,
IOException,
org.jolokia.server.core.request.NotChangedException,
org.jolokia.server.core.request.EmptyResponseException

Abstract method to be subclassed by a concrete handler for performing the request.

Parameters:

server - server to try

request - request to process

Returns:

the object result from the request

Throws:

InstanceNotFoundException

AttributeNotFoundException

ReflectionException

MBeanException

IOException

org.jolokia.server.core.request.NotChangedException

org.jolokia.server.core.request.EmptyResponseException

doHandleAllServerRequest

protected Object doHandleAllServerRequest(org.jolokia.server.core.util.jmx.MBeanServerAccess serverManager,
 R request,
 Object pPreviousResult)
                                   throws InstanceNotFoundException,
AttributeNotFoundException,
ReflectionException,
MBeanException,
IOException,
org.jolokia.server.core.request.NotChangedException,
org.jolokia.server.core.request.EmptyResponseException

Default implementation fo handling a request for multiple servers at once. A subclass, which returns, true on handleAllServersAtOnce(JolokiaRequest), needs to override this method.

Parameters:

serverManager - all MBean servers found in this JVM

request - the original request

pPreviousResult - a previous result which for merging requests can be used to merge files

Returns:

the result of the the request.

Throws:

IOException

AttributeNotFoundException

InstanceNotFoundException

MBeanException

ReflectionException

org.jolokia.server.core.request.NotChangedException

org.jolokia.server.core.request.EmptyResponseException

destroy

public void destroy()
             throws JMException

Lifecycle method called when agent goes down. Should be overridden by a handler if required.

Specified by:

destroy in interface CommandHandler<R extends org.jolokia.server.core.request.JolokiaRequest>

Throws:

JMException

checkForModifiedSince

protected void checkForModifiedSince(org.jolokia.server.core.util.jmx.MBeanServerAccess pServerManager,
 org.jolokia.server.core.request.JolokiaRequest pRequest)
                              throws org.jolokia.server.core.request.NotChangedException

Check, whether the set of MBeans for any managed MBeanServer has been change since the timestamp provided in the given request

Parameters:

pServerManager - manager for all MBeanServers

pRequest - the request from where to fetch the timestamp

Throws:

org.jolokia.server.core.request.NotChangedException - if there has been no REGISTER/UNREGISTER notifications in the meantime