org.jolokia.backend.executor

Interface MBeanServerExecutor

All Known Subinterfaces:

MBeanPluginContext

All Known Implementing Classes:

AbstractMBeanServerExecutor, MBeanServerExecutorLocal

public interface MBeanServerExecutor

An MBeanSever executor is responsible to perform actions on one or more MBeanServers which involve operations on one or more MBeans. It encapsulates completely all available MBeanServers, so no direct access to the MBeanServers are required. This interface is also suitable for implementations with remote MBeanServerConnections, e.g. for implementing it with JSR-160 connections. A MBeanServerExecutor is used

Since:

17.01.13

Author:

roland

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	MBeanServerExecutor.MBeanAction<R> A MBeanAction represent a single action on a MBeanServer for a given object name.
static interface	MBeanServerExecutor.MBeanEachCallback This callback is used together with each(ObjectName, MBeanEachCallback) for iterating over all active MBeanServers.

Method Summary

Methods

Modifier and Type	Method and Description
<R> R	call(ObjectName pObjectName, MBeanServerExecutor.MBeanAction<R> pMBeanAction, Object... pExtraArgs) Call an action an the first MBeanServer on which the action does not throw an InstanceNotFoundException will considered to be successful and this method returns with the return value of the succesful action.
void	each(ObjectName pObjectName, MBeanServerExecutor.MBeanEachCallback pCallback) Iterate over all MBeanServers managed and call the handler via a callback.
boolean	hasMBeansListChangedSince(long pTimestamp) Check whether the set of MBeans in all managed MBeanServer has been changed since the given time.
Set<ObjectName>	queryNames(ObjectName pObjectName) Query all MBeanServer and return the union of all results

Method Detail

each

void each(ObjectName pObjectName,
        MBeanServerExecutor.MBeanEachCallback pCallback)
          throws IOException,
                 ReflectionException,
                 MBeanException

Iterate over all MBeanServers managed and call the handler via a callback. If is null or a pattern, the MBean names are queried on each MBeanServer and feed into the callback. If it is a full object name, then all MBeanServers are called with this object name in turn.

Parameters:

pObjectName - object name to lookup, which can be a pattern in which case a query is performed.

pCallback - the action to be called for each MBean found on every server

Throws:

IOException

ReflectionException

MBeanException

call

<R> R call(ObjectName pObjectName,
         MBeanServerExecutor.MBeanAction<R> pMBeanAction,
         Object... pExtraArgs)
       throws IOException,
              ReflectionException,
              MBeanException,
              AttributeNotFoundException,
              InstanceNotFoundException

Call an action an the first MBeanServer on which the action does not throw an InstanceNotFoundException will considered to be successful and this method returns with the return value of the succesful action. If no action was succesful, an IllegalArgumentException is raised (containing the last InstanceNotFoundException from the last tried server)

Type Parameters:

R - type of the return value

Parameters:

pObjectName - objectname given through to the action

pMBeanAction - the action to call

pExtraArgs - any extra args given also to the action

Returns:

the return value of the succesful action

Throws:

IOException

ReflectionException

MBeanException - if the JMX call causes an issue

AttributeNotFoundException

InstanceNotFoundException

queryNames

Set<ObjectName> queryNames(ObjectName pObjectName)
                           throws IOException

Query all MBeanServer and return the union of all results

Parameters:

pObjectName - pattern to query for. If null, then all MBean of all MBeanServers are returned

Returns:

the found MBeans

Throws:

IOException - if called remotely and an IOError occured.

hasMBeansListChangedSince

boolean hasMBeansListChangedSince(long pTimestamp)

Check whether the set of MBeans in all managed MBeanServer has been changed since the given time. The input is the epoch time in seconds, however, milliseconds would be much more appropriate. However, the Jolokia responses contain currently time measured in seconds. This should be changed in a future version, but this implies a quite heavy API changed (and if this is changed, the key "timestamp" should be changed to "time", too, in order to fail early in case of problems). In order to avoid inconsistencies for sub-second updates, we are comparing conservatively (so hasBeenUpdated might return "true" more often than required).

Parameters:

pTimestamp - seconds since 1.1.1970

Returns:

true if the MBeans has been updated since this time, false otherwise