DefaultMOServer (SNMP4J-Agent 2.7.2)

java.lang.Object
- org.snmp4j.agent.DefaultMOServer

All Implemented Interfaces:

MOServer
```
public class DefaultMOServer
extends Object
implements MOServer
```
The default MO server implementation uses a sorted map for the managed object registry.

Version:

2.4.0

Author:

Frank Fock

Constructor Summary

Constructors
Constructor and Description

DefaultMOServer()

Constructors
Constructor and Description
`DefaultMOServer()`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addContext(org.snmp4j.smi.OctetString context)` Adds the supplied context to the server.
`void`	`addContextListener(ContextListener l)` Adds a context listener to the server.
`void`	`addLookupListener(MOServerLookupListener listener, ManagedObject mo)` Adds a managed object lookup listener for the supplied managed object to this managed object server.
`protected void`	`checkForUpdate(UpdatableManagedObject mo, MOQuery query)` Checks `updateStrategy` whether the queried managed object needs to be updated.
`protected void`	`fireContextChanged(ContextEvent event)`
`protected void`	`fireLookupEvent(ManagedObject mo, MOQuery query)`
`protected void`	`fireQueryEvent(ManagedObject mo, MOQuery query)`
`org.snmp4j.smi.OctetString[]`	`getContexts()` Returns the contexts known by the server.
`MOLockStrategy`	`getLockStrategy()` Return the locking strategy for this server.
`ManagedObject`	`getManagedObject(org.snmp4j.smi.OID key, org.snmp4j.smi.OctetString context)` Returns the `ManagedObject` with the specified `OID` as ID returned by `RegisteredManagedObject.getID()` or the lower bound (regardless whether the ManagedObject's scope includes it or not) when registered in the supplied context.
`ManagedObject`	`getManagedObject(org.snmp4j.smi.OID key, org.snmp4j.smi.OctetString context, boolean fireLookupEvents)` Returns the `ManagedObject` with the specified `OID` as ID returned by `RegisteredManagedObject.getID()` or the lower bound (regardless whether the ManagedObject's scope includes it or not) when registered in the supplied context.
`org.snmp4j.smi.OctetString[]`	`getRegisteredContexts(ManagedObject managedObject)` Returns the contexts for which the supplied `ManagedObject` has been registered.
`SortedMap<MOScope,ManagedObject>`	`getRegistry()`
`UpdateStrategy`	`getUpdateStrategy()` Gets the update strategy for `UpdatableManagedObject`s.
`static org.snmp4j.smi.Variable`	`getValue(MOServer server, org.snmp4j.smi.OctetString context, org.snmp4j.smi.OID key)` Returns the value of a particular MIB object instance using the `ManagedObjectValueAccess` interface.
`boolean`	`isContextSupported(org.snmp4j.smi.OctetString context)` Checks whether the supplied context is supported (registered) by this server.
`Iterator<Map.Entry<MOScope,ManagedObject>>`	`iterator()` Return a read-only `Iterator` over the content of this server.
`boolean`	`lock(Object owner, ManagedObject managedObject)` Locks a ManagedObject by the supplied owner.
`boolean`	`lock(Object owner, ManagedObject managedObject, long timeoutMillis)` Locks a ManagedObject by the supplied owner.
`ManagedObject`	`lookup(MOQuery query)` Lookup the first (lexicographically ordered) managed object that matches the supplied query.
`ManagedObject`	`lookup(MOQuery query, LockRequest lockRequest)` Lookup the first (lexicographically ordered) managed object that matches the supplied query.
`void`	`register(ManagedObject mo, org.snmp4j.smi.OctetString context)` Registers a managed object for the specified context.
`static <R extends MOTableRow,T extends MOTable<R,? extends MOColumn,? extends MOTableModel<R>>> void`	`registerTableRowListener(MOServer server, MOTableRowListener<R> listener)` Register a single `MOTableRowListener` with all tables in the specified `MOServer`.
`void`	`removeContext(org.snmp4j.smi.OctetString context)` Removes a context from the server.
`void`	`removeContextListener(ContextListener l)` Removes a previously added context listener.
`boolean`	`removeLookupListener(MOServerLookupListener listener, ManagedObject mo)` Removes a managed object lookup listener for the specified managed object.
`void`	`setLockStrategy(MOLockStrategy lockStrategy)` Sets the lock strategy for this server.
`void`	`setUpdateStrategy(UpdateStrategy updateStrategy)` Sets the update strategy for `UpdatableManagedObject`s.
`static boolean`	`setValue(MOServer server, org.snmp4j.smi.OctetString context, org.snmp4j.smi.VariableBinding newValueAndKey)` Sets the value of a particular MIB object instance using the `ManagedObjectValueAccess` interface.
`String`	`toString()`
`boolean`	`unlock(Object owner, ManagedObject managedObject)` Unlocks a ManagedObject that has been locked by the specified owner.
`ManagedObject`	`unregister(ManagedObject mo, org.snmp4j.smi.OctetString context)` Removes the registration of the supplied managed object for the specified context.
`static <R extends MOTableRow,T extends MOTable<R,? extends MOColumn,? extends MOTableModel<R>>> void`	`unregisterTableRowListener(MOServer server, MOTableRowListener<R> listener)` Unregister a single `MOTableRowListener` with all tables in the specified `MOServer`.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - DefaultMOServer
```
public DefaultMOServer()
```
- Method Detail
  - lookup
```
public ManagedObject lookup(MOQuery query)
```
    Description copied from interface: MOServer
    
    Lookup the first (lexicographically ordered) managed object that matches the supplied query. No locking will be performed, regardless of the set MOLockStrategy.
    
    Specified by:
    
    lookup in interface MOServer
    
    Parameters:
    
    query - a MOQuery instance.
    
    Returns:
    
    the ManagedObject that matches the query and null if no such object exists.
  - lookup
```
public ManagedObject lookup(MOQuery query,
                            LockRequest lockRequest)
```
    Description copied from interface: MOServer
    
    Lookup the first (lexicographically ordered) managed object that matches the supplied query. Locking will be performed according to the set MOLockStrategy before the lookup listener is fired. CAUTION: To make sure that the acquired lock is released after the using of the managed object has been finished, the MOServer.unlock(Object, ManagedObject) method must be called then.
    
    Specified by:
    
    lookup in interface MOServer
    
    Parameters:
    
    query - a MOQuery instance.
    
    lockRequest - the LockRequest that holds the lock owner and the timeout for acquiring a lock and returns whether a lock has been acquired or not on behalf of this lookup operation.
    
    Returns:
    
    the ManagedObject that matches the query and null if no such object exists.
  - getLockStrategy
```
public MOLockStrategy getLockStrategy()
```
    Return the locking strategy for this server. The strategy defines if a lock is acquired before a looked up ManagedObject is returned (and before the corresponding lookup event is being fired) or not.
    
    Returns:
    
    the managed object locking strategy instance used by this server. If null, no locking is performed at all (which is only recommended for static content servers).
    
    Since:
    
    2.4.0
  - setLockStrategy
```
public void setLockStrategy(MOLockStrategy lockStrategy)
```
    Sets the lock strategy for this server. The strategy defines if a lock is acquired before a looked up ManagedObject is returned (and before the corresponding lookup event is being fired) or not. By default, only write access needs a lock.
    
    Parameters:
    
    lockStrategy - a MOLockStrategy instance or null to suppress any locking.
    
    Since:
    
    2.4.0
  - checkForUpdate
```
protected void checkForUpdate(UpdatableManagedObject mo,
                              MOQuery query)
```
    Checks updateStrategy whether the queried managed object needs to be updated. This method is called on behalf of lookup(MOQuery query) after fireQueryEvent(org.snmp4j.agent.ManagedObject, org.snmp4j.agent.MOQuery) and before fireLookupEvent(org.snmp4j.agent.ManagedObject, org.snmp4j.agent.MOQuery) is being called.
    
    Parameters:
    
    mo - an UpdatableManagedObject instance.
    
    query - the query that is interested in content of mo.
    
    Since:
    
    1.2
  - getManagedObject
```
public ManagedObject getManagedObject(org.snmp4j.smi.OID key,
                                      org.snmp4j.smi.OctetString context,
                                      boolean fireLookupEvents)
```
    Returns the ManagedObject with the specified OID as ID returned by RegisteredManagedObject.getID() or the lower bound (regardless whether the ManagedObject's scope includes it or not) when registered in the supplied context.
    Note: The query used to lookup the managed object will indicate an intended read-only access for the MOServerLookupEvents fired on behalf of this method.
    
    Parameters:
    
    key - the OID identifying the key (lower bound) of the ManagedObject.
    
    context - the optional context to look in. A null value searches in all contexts.
    
    fireLookupEvents - if true lookup and query events will be fired as if the managed objects has been looked up by lookup(MOQuery). In addition, if the looked up managed object is an UpdatableManagedObject it will be locked if the lock strategy of this server requires it. The lock is active until the look up events have been fired completely. The lock operation waits without timeout for the lock to become available. Otherwise, no events will be fired at all.
    
    Returns:
    
    the ManagedObject instance or null if such an instance does not exists.
    
    Since:
    
    2.3
  - getManagedObject
```
public ManagedObject getManagedObject(org.snmp4j.smi.OID key,
                                      org.snmp4j.smi.OctetString context)
```
    Returns the ManagedObject with the specified OID as ID returned by RegisteredManagedObject.getID() or the lower bound (regardless whether the ManagedObject's scope includes it or not) when registered in the supplied context. Note: The query used to lookup the managed object will indicate an intended read-only access for the MOServerLookupEvents fired on behalf of this method.
    
    Parameters:
    
    key - the OID identifying the key (lower bound) of the ManagedObject.
    
    context - the optional context to look in. A null value searches in all contexts.
    
    Returns:
    
    the ManagedObject instance or null if such an instance does not exists.
    
    Since:
    
    1.1
  - getValue
```
public static org.snmp4j.smi.Variable getValue(MOServer server,
                                               org.snmp4j.smi.OctetString context,
                                               org.snmp4j.smi.OID key)
```
    Returns the value of a particular MIB object instance using the ManagedObjectValueAccess interface. If a ManagedObject does not support this interface, its value cannot be returned and null will be returned instead. Note: This method does not perform any locking based on the MOLockStrategy.
    
    Parameters:
    
    server - the MOServer where to lookup the value.
    
    context - the optional context to look in. A null value searches in all contexts.
    
    key - the OID identifying the variable instance to return.
    
    Returns:
    
    the Variable associated with OID and context in server or null if no such variable exists.
    
    Since:
    
    1.4
  - setValue
```
public static boolean setValue(MOServer server,
                               org.snmp4j.smi.OctetString context,
                               org.snmp4j.smi.VariableBinding newValueAndKey)
```
    Sets the value of a particular MIB object instance using the ManagedObjectValueAccess interface. If a ManagedObject does not support this interface, its value cannot be set and false will be returned. Note: This method does not perform any locking based on the MOLockStrategy.
    
    Parameters:
    
    server - the MOServer where to lookup the value.
    
    context - the optional context to look in. A null value searches in all contexts.
    
    newValueAndKey - the OID identifying the variable instance to set and its new value.
    
    Returns:
    
    the true if the value has been set successfully, false otherwise.
    
    Since:
    
    1.4
  - fireLookupEvent
```
protected void fireLookupEvent(ManagedObject mo,
                               MOQuery query)
```
  - fireQueryEvent
```
protected void fireQueryEvent(ManagedObject mo,
                              MOQuery query)
```
  - getContexts
```
public org.snmp4j.smi.OctetString[] getContexts()
```
    Description copied from interface: MOServer
    
    Returns the contexts known by the server.
    
    Specified by:
    
    getContexts in interface MOServer
    
    Returns:
    
    an array of context names.
  - isContextSupported
```
public boolean isContextSupported(org.snmp4j.smi.OctetString context)
```
    Description copied from interface: MOServer
    
    Checks whether the supplied context is supported (registered) by this server.
    
    Specified by:
    
    isContextSupported in interface MOServer
    
    Parameters:
    
    context - a context name.
    
    Returns:
    
    true if the context is support (thus has previously added by MOServer.addContext(org.snmp4j.smi.OctetString)) and false otherwise.
  - getRegistry
```
public SortedMap<MOScope,ManagedObject> getRegistry()
```
  - getUpdateStrategy
```
public UpdateStrategy getUpdateStrategy()
```
    Gets the update strategy for UpdatableManagedObjects. If the strategy is null no updates will be performed on behalf of calls to lookup(org.snmp4j.agent.MOQuery).
    
    Returns:
    
    the current UpdateStrategy instance or null if no strategy is active.
    
    Since:
    
    1.2
    
    See Also:
    
    lookup(org.snmp4j.agent.MOQuery)
  - setUpdateStrategy
```
public void setUpdateStrategy(UpdateStrategy updateStrategy)
```
    Sets the update strategy for UpdatableManagedObjects. If the strategy is null no updates will be performed on behalf of calls to lookup(MOQuery).
    
    Parameters:
    
    updateStrategy - the new UpdateStrategy instance or null if no updates should be performed.
    
    Since:
    
    1.2
    
    See Also:
    
    lookup(MOQuery)
  - register
```
public void register(ManagedObject mo,
                     org.snmp4j.smi.OctetString context)
              throws DuplicateRegistrationException
```
    Description copied from interface: MOServer
    
    Registers a managed object for the specified context. A managed object can be registered for more than one context.
    
    Specified by:
    
    register in interface MOServer
    
    Parameters:
    
    mo - a ManagedObject instance.
    
    context - the context name for which to register the mo or null if the managed oject is to be registered for all contexts (including the default context).
    
    Throws:
    
    DuplicateRegistrationException - if the registration conflicts (i.e. overlaps) with an already existing registration.
  - unregister
```
public ManagedObject unregister(ManagedObject mo,
                                org.snmp4j.smi.OctetString context)
```
    Description copied from interface: MOServer
    
    Removes the registration of the supplied managed object for the specified context.
    
    Specified by:
    
    unregister in interface MOServer
    
    Parameters:
    
    mo - a ManagedObject instance.
    
    context - the context name for which to unregister the mo or null if the managed object is to be unregistered for all contexts (including the default context). In the latter case however, explicit registrations for a particular context will not be removed!
    
    Returns:
    
    the removed ManagedObjectinstance or null if the removal failed.
  - addContext
```
public void addContext(org.snmp4j.smi.OctetString context)
```
    Description copied from interface: MOServer
    
    Adds the supplied context to the server. The server however may silently ignore the request if local constraints do not allow to add the context (although this should be an exception case only).
    
    Specified by:
    
    addContext in interface MOServer
    
    Parameters:
    
    context - an OctetString representing the context name to add.
  - removeContext
```
public void removeContext(org.snmp4j.smi.OctetString context)
```
    Description copied from interface: MOServer
    
    Removes a context from the server. Removing a context does not remove any managed objects from the server's registry.
    
    Specified by:
    
    removeContext in interface MOServer
    
    Parameters:
    
    context - n OctetString representing the context name to remove.
  - lock
```
public boolean lock(Object owner,
                    ManagedObject managedObject)
```
    Description copied from interface: MOServer
    
    Locks a ManagedObject by the supplied owner. Once a ManagedObject is locked, a lookup attempt will block until it is unlocked or a predefined timeout occurs.
    
    Specified by:
    
    lock in interface MOServer
    
    Parameters:
    
    owner - an Object.
    
    managedObject - the ManagedObject to lock.
    
    Returns:
    
    true if the lock could be acquired, false otherwise, i.e. if an InterruptedException has occurred.
  - lock
```
public boolean lock(Object owner,
                    ManagedObject managedObject,
                    long timeoutMillis)
```
    Description copied from interface: MOServer
    
    Locks a ManagedObject by the supplied owner. Once a ManagedObject is locked, a lookup attempt will block until it is unlocked or a predefined timeout occurs.
    
    Specified by:
    
    lock in interface MOServer
    
    Parameters:
    
    owner - an Object.
    
    managedObject - the ManagedObject to lock.
    
    timeoutMillis - the number of 1/1000 seconds to wait for the lock. 0 or less disables the timeout and waits forever until the lock is released by the current owner.
    
    Returns:
    
    true if the lock could be acquired, false otherwise, i.e. if an InterruptedException or timeout has occurred.
  - unlock
```
public boolean unlock(Object owner,
                      ManagedObject managedObject)
```
    Description copied from interface: MOServer
    
    Unlocks a ManagedObject that has been locked by the specified owner. If the ManagedObject is currently locked by another owner this method returns silently.
    Note: In debug log mode a message is locked if the lock owner does not match the current lock owner.
    
    Specified by:
    
    unlock in interface MOServer
    
    Parameters:
    
    owner - an Object.
    
    managedObject - the ManagedObject to unlock. If managedObject is null then this call has no effect.
    
    Returns:
    
    true if the lock has been found and released successfully, false otherwise.
  - iterator
```
public Iterator<Map.Entry<MOScope,ManagedObject>> iterator()
```
    Description copied from interface: MOServer
    
    Return a read-only Iterator over the content of this server. The iterator is thread safe and can be used while the server is being modified. The remove operation of the iterator is not supported.
    
    Specified by:
    
    iterator in interface MOServer
    
    Returns:
    
    the Iterator on the Map.Entry instances managed by this server. Each Entry consists of an MOScope key instance and a corresponding ManagedObject value instance. If the ManagedObject has been registered for a specific context, then a MOContextScope is returned as key, otherwise the managed objects own MOScope is returned.
  - addLookupListener
```
public void addLookupListener(MOServerLookupListener listener,
                              ManagedObject mo)
```
    Description copied from interface: MOServer
    
    Adds a managed object lookup listener for the supplied managed object to this managed object server. A MOServerLookupListener is called before the managed object is returned by MOServer.lookup(MOQuery query).
    
    Specified by:
    
    addLookupListener in interface MOServer
    
    Parameters:
    
    listener - a MOServerLookupListener instance, for example a managed object that needs to update its state whenever it has been looked up
    
    mo - the ManagedObject that triggers the MOServerLookupEvent to be fired when it has been looked up.
  - removeLookupListener
```
public boolean removeLookupListener(MOServerLookupListener listener,
                                    ManagedObject mo)
```
    Description copied from interface: MOServer
    
    Removes a managed object lookup listener for the specified managed object.
    
    Specified by:
    
    removeLookupListener in interface MOServer
    
    Parameters:
    
    listener - a MOServerLookupListener instance.
    
    mo - the ManagedObject that triggered the MOServerLookupEvent to be fired when it has been looked up.
    
    Returns:
    
    true if the listener could be removed or false if such a listener is not registered.
  - addContextListener
```
public void addContextListener(ContextListener l)
```
    Description copied from interface: MOServer
    
    Adds a context listener to the server. The listener will be informed about context insertion and removal.
    
    Specified by:
    
    addContextListener in interface MOServer
    
    Parameters:
    
    l - a ContextListener instance to be informed about context changes.
  - removeContextListener
```
public void removeContextListener(ContextListener l)
```
    Description copied from interface: MOServer
    
    Removes a previously added context listener.
    
    Specified by:
    
    removeContextListener in interface MOServer
    
    Parameters:
    
    l - a ContextListener instance.
  - fireContextChanged
```
protected void fireContextChanged(ContextEvent event)
```
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - getRegisteredContexts
```
public org.snmp4j.smi.OctetString[] getRegisteredContexts(ManagedObject managedObject)
```
    Description copied from interface: MOServer
    
    Returns the contexts for which the supplied ManagedObject has been registered.
    
    Specified by:
    
    getRegisteredContexts in interface MOServer
    
    Parameters:
    
    managedObject - a ManagedObject instance.
    
    Returns:
    
    an array of context strings, for which managedObject has been registered. If the managedObject has been registered for all contexts, a null element is included in the array.
  - registerTableRowListener
```
public static <R extends MOTableRow,T extends MOTable<R,? extends MOColumn,? extends MOTableModel<R>>> void registerTableRowListener(MOServer server,
                                                                                                                                     MOTableRowListener<R> listener)
```
    Register a single MOTableRowListener with all tables in the specified MOServer. This overall registration can be used, for example, to apply table size limits to all tables in an agent. See MOTableSizeLimit for details.
    Note: The server must not change its registration content while this method is being called, otherwise a ConcurrentModificationException might be thrown.
    
    Type Parameters:
    
    R - the MOTableRow type supported by the table row listener to register.
    
    T - the MOTable type supported by the table row listener to register.
    
    Parameters:
    
    server - a MOServer instance.
    
    listener - the MOTableRowListener instance to register.
    
    Since:
    
    1.4
  - unregisterTableRowListener
```
public static <R extends MOTableRow,T extends MOTable<R,? extends MOColumn,? extends MOTableModel<R>>> void unregisterTableRowListener(MOServer server,
                                                                                                                                       MOTableRowListener<R> listener)
```
    Unregister a single MOTableRowListener with all tables in the specified MOServer. This overall unregistration can be used, for example, to remove table size limits from all tables in an agent. See MOTableSizeLimit for details. Note: The server must not change its registration content while this method is being called, otherwise a ConcurrentModificationException might be thrown.
    
    Type Parameters:
    
    R - the MOTableRow type supported by the table row listener to register.
    
    T - the MOTable type supported by the table row listener to register.
    
    Parameters:
    
    server - a MOServer instance.
    
    listener - the MOTableRowListener instance to unregister.
    
    Since:
    
    1.4

Class DefaultMOServer

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

DefaultMOServer

Method Detail

lookup

lookup

getLockStrategy

setLockStrategy

checkForUpdate

getManagedObject

getManagedObject

getValue

setValue

fireLookupEvent

fireQueryEvent

getContexts

isContextSupported

getRegistry

getUpdateStrategy

setUpdateStrategy

register

unregister

addContext

removeContext

lock

lock

unlock

iterator

addLookupListener

removeLookupListener

addContextListener

removeContextListener

fireContextChanged

toString

getRegisteredContexts

registerTableRowListener

unregisterTableRowListener