MOScalar (SNMP4J-Agent 2.7.2)

java.lang.Object
- org.snmp4j.agent.mo.MOScalar<V>

All Implemented Interfaces:

ManagedObject, ManagedObjectValueAccess, MOScope, RegisteredManagedObject, SerializableManagedObject

Direct Known Subclasses:

AgentppSimulationMib.AgentppSimDeleteRow, AgentppSimulationMib.AgentppSimDeleteTableContents, DateAndTimeScalar, DisplayStringScalar, EnumeratedScalar, NotificationLogMib.NlmConfigGlobalAgeOut, NotificationLogMib.NlmConfigGlobalEntryLimit, SnmpTsmMib.SnmpTsmConfigurationUsePrefix, SNMPv2MIB.SysUpTimeImpl, TestAndIncr, TimeStampScalar
```
public class MOScalar<V extends org.snmp4j.smi.Variable>
extends Object
implements ManagedObject, MOScope, SerializableManagedObject, ManagedObjectValueAccess
```
The MOScalar class represents scalar SNMP managed objects. Subclasses might support Java serialization for this class. SNMP4J serialization is provided in any case by the SerializableManagedObject interface.

Version:

2.4.1

Author:

Frank Fock

Field Summary

Fields
Modifier and Type Field and Description

protected MOAccess access

protected org.snmp4j.smi.OID oid

Fields
Modifier and Type	Field and Description
`protected MOAccess`	`access`
`protected org.snmp4j.smi.OID`	`oid`

Constructor Summary

Constructors
Modifier	Constructor and Description
`protected`	`MOScalar()` Construct a MOScalar for deserialization.
	`MOScalar(org.snmp4j.smi.OID id, MOAccess access, V value)` Creates a scalar MO instance with OID, maximum access level and initial value.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addMOChangeListener(MOChangeListener l)` Adds a `MOChangeListener` that needs to be informed about state changes of this scalar.
`void`	`addMOValueValidationListener(MOValueValidationListener l)` Adds a value validation listener to check new values.
`protected int`	`changeValue(V value)` Changes the value of this scalar on behalf of a commit or undo operation.
`protected boolean`	`checkRequestScope(SubRequest request)` Checks whether the request is within the scope of this scalar or not.
`void`	`cleanup(SubRequest request)` Cleansup a (sub)request and frees all resources locked during the preparation phase.
`void`	`commit(SubRequest request)` Commits a previously prepared SET (sub)request.
`boolean`	`covers(org.snmp4j.smi.OID oid)` Checks if this scope covers the supplied OID.
`org.snmp4j.smi.OID`	`find(MOScope range)` Finds the first object ID (OID) in the specified search range.
`protected void`	`fireAfterMOChange(MOChangeEvent changeEvent)`
`protected void`	`fireAfterPrepareMOChange(MOChangeEvent changeEvent)`
`protected void`	`fireBeforeMOChange(MOChangeEvent changeEvent)`
`protected void`	`fireBeforePrepareMOChange(MOChangeEvent changeEvent)`
`protected void`	`fireValidate(MOValueValidationEvent validationEvent)`
`void`	`get(SubRequest request)` Processes a GET request and return the result in the supplied sub-request.
`MOAccess`	`getAccess()` Gets the access object for this scalar.
`org.snmp4j.smi.OID`	`getID()` Gets the unique object ID of the managed object.
`org.snmp4j.smi.OID`	`getLowerBound()` Gets the lower bound OID of the scope.
`org.snmp4j.smi.OID`	`getOid()` Gets the instance OID of this scalar managed object.
`MOScope`	`getScope()` Returns the scope of OIDs that are covered by this scalar's object registration.
`MOScope`	`getSingleInstanceScope()` Returns a scope that covers only the scalar instance itself without any possible OIDs down in the tree or at the same level.
`org.snmp4j.smi.OID`	`getUpperBound()` Gets the upper bound OID of the scope.
`V`	`getValue()` Returns the actual value of this scalar managed object.
`org.snmp4j.smi.Variable`	`getValue(org.snmp4j.smi.OID instanceOID)` Returns the variable (a copy thereof) with the specified instance OID managed by this `ManagedObject`.
`boolean`	`isCovered(MOScope other)` Checks whether the supplied scope is covered by this scope.
`boolean`	`isLowerIncluded()` Indicates whether the lower bound OID is included in the scope or not.
`boolean`	`isOverlapping(MOScope other)` Checks whether the supplied scope overlap with this one, thus sharing at least one OID with the supplied one.
`boolean`	`isUpperIncluded()` Indicates whether the upper bound OID is included in the scope or not.
`int`	`isValueOK(SubRequest request)` Checks whether the new value contained in the supplied sub-request is a valid value for this object.
`boolean`	`isVolatile()` Tests if this instance of a SerializableManagedObject should be serialized or deserialized through persistent storage load or save operation.
`void`	`load(MOInput input)` Loads the content of the managed object from the specified input (stream).
`boolean`	`next(SubRequest request)` Finds the successor instance for the object instance ID (OID) given by the supplied sub-request and returns it within the supplied sub-request object.
`void`	`prepare(SubRequest request)` Prepares a SET (sub)request.
`void`	`removeMOChangeListener(MOChangeListener l)` Removes a `MOChangeListener`.
`void`	`removeMOValueValidationListener(MOValueValidationListener l)` Removes a value validation listener
`void`	`save(MOOutput output)` Saves the (non-volatile) content of this managed object to the specified output (stream).
`int`	`setValue(V value)` Sets the value of this scalar managed object without checking it for the correct syntax.
`boolean`	`setValue(org.snmp4j.smi.VariableBinding newValueAndInstancceOID)` Sets the value of a particular MIB object instance managed by this `ManagedObject`.
`void`	`setVolatile(boolean isVolatile)` Sets the volatile flag for this instance.
`String`	`toString()`
`protected String`	`toStringDetails()`
`void`	`undo(SubRequest request)` Compensates (undo) a (sub)request when a commit of another subrequest failed with an error.

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

- Field Detail
  - oid
```
protected org.snmp4j.smi.OID oid
```
  - access
```
protected MOAccess access
```
- Constructor Detail
  - MOScalar
```
protected MOScalar()
```
    Construct a MOScalar for deserialization. If used by a subclass, make sure the oid and access members are set before the scalar is registered with a MOServer instance. The oid must not be changed or modified afterwards!
    
    Since:
    
    2.4.1
  - MOScalar
```
public MOScalar(org.snmp4j.smi.OID id,
                MOAccess access,
                V value)
```
    Creates a scalar MO instance with OID, maximum access level and initial value.
    
    Parameters:
    
    id - the instance OID of the scalar instance (last sub-identifier should be zero).
    
    access - the maximum access level supported by this instance.
    
    value - the initial value of the scalar instance. If the initial value is null or a Counter syntax, the scalar is created as a volatile (non-persistent) instance by default.
- Method Detail
  - getScope
```
public MOScope getScope()
```
    Returns the scope of OIDs that are covered by this scalar's object registration. This range is 1.3.6...n <= x < 1.3.6...n+1 where n is the last subidentifier of the OID registered by the corresponding OBJECT-TYPE definition. Prior to version 1.1.2, this method returned a scope equal to the scope now returned by getSingleInstanceScope().
    
    Specified by:
    
    getScope in interface ManagedObject
    
    Returns:
    
    a MOScope that covers the OIDs by this scalar object registration.
  - getSingleInstanceScope
```
public MOScope getSingleInstanceScope()
```
    Returns a scope that covers only the scalar instance itself without any possible OIDs down in the tree or at the same level.
    
    Returns:
    
    a scope that covers exactly the OID of this scalar.
    
    Since:
    
    1.1.2
  - find
```
public org.snmp4j.smi.OID find(MOScope range)
```
    Description copied from interface: ManagedObject
    
    Finds the first object ID (OID) in the specified search range.
    
    Specified by:
    
    find in interface ManagedObject
    
    Parameters:
    
    range - the MOScope for the search.
    
    Returns:
    
    the OID that is included in the search range and null if no such instances could be found.
  - get
```
public void get(SubRequest request)
```
    Description copied from interface: ManagedObject
    
    Processes a GET request and return the result in the supplied sub-request.
    
    Specified by:
    
    get in interface ManagedObject
    
    Parameters:
    
    request - the SubRequest to process.
  - getAccess
```
public MOAccess getAccess()
```
    Gets the access object for this scalar.
    
    Returns:
    
    the access instance associated with this scalar.
    
    Since:
    
    1.2
  - checkRequestScope
```
protected boolean checkRequestScope(SubRequest request)
```
    Checks whether the request is within the scope of this scalar or not.
    
    Parameters:
    
    request - a SubRequest.
    
    Returns:
    
    true if the request is within scope and false otherwise. In the latter case, the variable of the request is set to Null.noSuchInstance and the request is marked completed.
  - next
```
public boolean next(SubRequest request)
```
    Description copied from interface: ManagedObject
    
    Finds the successor instance for the object instance ID (OID) given by the supplied sub-request and returns it within the supplied sub-request object.
    
    Specified by:
    
    next in interface ManagedObject
    
    Parameters:
    
    request - the SubRequest to process.
    
    Returns:
    
    true if the search request found an appropriate instance, false otherwise.
  - isValueOK
```
public int isValueOK(SubRequest request)
```
    Checks whether the new value contained in the supplied sub-request is a valid value for this object. The checks are performed by firing a MOValueValidationEvent the registered listeners.
    
    Parameters:
    
    request - the SubRequest with the new value.
    
    Returns:
    
    SnmpConstants.SNMP_ERROR_SUCCESS if the new value is OK, any other appropriate SNMPv2/v3 error status if not.
  - prepare
```
public void prepare(SubRequest request)
```
    Description copied from interface: ManagedObject
    
    Prepares a SET (sub)request. This method represents the first phase of a two phase commit. During preparation all necessary resources should be locked in order to be able to execute the commit without claiming additional resources.
    
    Specified by:
    
    prepare in interface ManagedObject
    
    Parameters:
    
    request - the SubRequest to process.
  - commit
```
public void commit(SubRequest request)
```
    Description copied from interface: ManagedObject
    
    Commits a previously prepared SET (sub)request. This is the second phase of a two phase commit. The change is committed but the resources locked during prepare not freed yet.
    
    Specified by:
    
    commit in interface ManagedObject
    
    Parameters:
    
    request - the SubRequest to process.
  - changeValue
```
protected int changeValue(V value)
```
    Changes the value of this scalar on behalf of a commit or undo operation. Overwrite this method for easy and simple instrumentation. By default setValue(Variable value) is called.
    
    Parameters:
    
    value - the new value.
    
    Returns:
    
    a SNMP error status if the operation failed (should be avoided).
    
    Since:
    
    1.2
  - undo
```
public void undo(SubRequest request)
```
    Description copied from interface: ManagedObject
    
    Compensates (undo) a (sub)request when a commit of another subrequest failed with an error. This also frees any resources locked during the preparation phase.
    
    Specified by:
    
    undo in interface ManagedObject
    
    Parameters:
    
    request - the SubRequest to process.
  - cleanup
```
public void cleanup(SubRequest request)
```
    Description copied from interface: ManagedObject
    
    Cleansup a (sub)request and frees all resources locked during the preparation phase.
    
    Specified by:
    
    cleanup in interface ManagedObject
    
    Parameters:
    
    request - the SubRequest to process.
  - getOid
```
public org.snmp4j.smi.OID getOid()
```
    Gets the instance OID of this scalar managed object.
    
    Returns:
    
    the instance OID (by reference).
  - getLowerBound
```
public org.snmp4j.smi.OID getLowerBound()
```
    Description copied from interface: MOScope
    
    Gets the lower bound OID of the scope. Whether the lower bound is included or excluded from the scope's region is determined by MOScope.isLowerIncluded().
    
    Specified by:
    
    getLowerBound in interface MOScope
    
    Returns:
    
    an OID.
  - getUpperBound
```
public org.snmp4j.smi.OID getUpperBound()
```
    Description copied from interface: MOScope
    
    Gets the upper bound OID of the scope. Whether the upper bound is included or excluded from the scope's region is determined by MOScope.isUpperIncluded().
    
    Specified by:
    
    getUpperBound in interface MOScope
    
    Returns:
    
    OID
  - isCovered
```
public boolean isCovered(MOScope other)
```
    Description copied from interface: MOScope
    
    Checks whether the supplied scope is covered by this scope.
    
    Specified by:
    
    isCovered in interface MOScope
    
    Parameters:
    
    other - the MOScope to check
    
    Returns:
    
    true if the lower bound of other is greater or equal than the lower bound of this scope and if the upper bound of other is lower or equal than the upper bound of this scope.
  - isLowerIncluded
```
public boolean isLowerIncluded()
```
    Description copied from interface: MOScope
    
    Indicates whether the lower bound OID is included in the scope or not.
    
    Specified by:
    
    isLowerIncluded in interface MOScope
    
    Returns:
    
    true if the lower bound is included.
  - isUpperIncluded
```
public boolean isUpperIncluded()
```
    Description copied from interface: MOScope
    
    Indicates whether the upper bound OID is included in the scope or not.
    
    Specified by:
    
    isUpperIncluded in interface MOScope
    
    Returns:
    
    true if the upper bound is included.
  - getValue
```
public V getValue()
```
    Returns the actual value of this scalar managed object. For a basic instrumentation, overwrite this method to provide always the actual value and/or to update the internal value member and then call super.getValue() in the derived class.
    
    Returns:
    
    a non null Variable with the same syntax defined for this scalar object.
  - isVolatile
```
public boolean isVolatile()
```
    Description copied from interface: SerializableManagedObject
    
    Tests if this instance of a SerializableManagedObject should be serialized or deserialized through persistent storage load or save operation.
    
    Specified by:
    
    isVolatile in interface SerializableManagedObject
    
    Returns:
    
    true if SerializableManagedObject.load(org.snmp4j.agent.io.MOInput) and SerializableManagedObject.save(org.snmp4j.agent.io.MOOutput) should not be called through a persistent storage operation and false if these method should be called.
  - setValue
```
public int setValue(V value)
```
    Sets the value of this scalar managed object without checking it for the correct syntax.
    
    Parameters:
    
    value - a Variable with the with the same syntax defined for this scalar object (not checked).
    
    Returns:
    
    a SNMP error code (zero indicating success by default).
  - setVolatile
```
public void setVolatile(boolean isVolatile)
```
    Sets the volatile flag for this instance.
    
    Parameters:
    
    isVolatile - if true the state of this object will not be persistently stored, otherwise the agent may save the state of this object persistently.
  - isOverlapping
```
public boolean isOverlapping(MOScope other)
```
    Description copied from interface: MOScope
    
    Checks whether the supplied scope overlap with this one, thus sharing at least one OID with the supplied one.
    
    Specified by:
    
    isOverlapping in interface MOScope
    
    Parameters:
    
    other - a MOScope.
    
    Returns:
    
    true if there exists at least one OID that is included in both scopes.
  - addMOValueValidationListener
```
public void addMOValueValidationListener(MOValueValidationListener l)
```
    Adds a value validation listener to check new values.
    
    Parameters:
    
    l - a MOValueValidationListener instance.
  - removeMOValueValidationListener
```
public void removeMOValueValidationListener(MOValueValidationListener l)
```
    Removes a value validation listener
    
    Parameters:
    
    l - a MOValueValidationListener instance.
  - fireValidate
```
protected void fireValidate(MOValueValidationEvent validationEvent)
```
  - getID
```
public org.snmp4j.smi.OID getID()
```
    Description copied from interface: RegisteredManagedObject
    
    Gets the unique object ID of the managed object.
    
    Specified by:
    
    getID in interface RegisteredManagedObject
    
    Returns:
    
    an OID.
  - load
```
public void load(MOInput input)
          throws IOException
```
    Description copied from interface: SerializableManagedObject
    
    Loads the content of the managed object from the specified input (stream).
    
    Specified by:
    
    load in interface SerializableManagedObject
    
    Parameters:
    
    input - a MOInput instance.
    
    Throws:
    
    IOException - if an MOInput operation fails.
  - save
```
public void save(MOOutput output)
          throws IOException
```
    Description copied from interface: SerializableManagedObject
    
    Saves the (non-volatile) content of this managed object to the specified output (stream).
    
    Specified by:
    
    save in interface SerializableManagedObject
    
    Parameters:
    
    output - a MOOutput instance.
    
    Throws:
    
    IOException - if an MOOutput operation fails.
  - covers
```
public boolean covers(org.snmp4j.smi.OID oid)
```
    Description copied from interface: MOScope
    
    Checks if this scope covers the supplied OID.
    
    Specified by:
    
    covers in interface MOScope
    
    Parameters:
    
    oid - an OID.
    
    Returns:
    
    true if oid is greater or equal the scope's lower bound and if it is less or equal its upper bound.
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - toStringDetails
```
protected String toStringDetails()
```
  - addMOChangeListener
```
public void addMOChangeListener(MOChangeListener l)
```
    Adds a MOChangeListener that needs to be informed about state changes of this scalar.
    
    Parameters:
    
    l - a MOChangeListener instance.
    
    Since:
    
    1.1
  - removeMOChangeListener
```
public void removeMOChangeListener(MOChangeListener l)
```
    Removes a MOChangeListener.
    
    Parameters:
    
    l - a MOChangeListener instance.
    
    Since:
    
    1.1
  - fireBeforePrepareMOChange
```
protected void fireBeforePrepareMOChange(MOChangeEvent changeEvent)
```
  - fireAfterPrepareMOChange
```
protected void fireAfterPrepareMOChange(MOChangeEvent changeEvent)
```
  - fireBeforeMOChange
```
protected void fireBeforeMOChange(MOChangeEvent changeEvent)
```
  - fireAfterMOChange
```
protected void fireAfterMOChange(MOChangeEvent changeEvent)
```
  - getValue
```
public org.snmp4j.smi.Variable getValue(org.snmp4j.smi.OID instanceOID)
```
    Description copied from interface: ManagedObjectValueAccess
    
    Returns the variable (a copy thereof) with the specified instance OID managed by this ManagedObject.
    
    Specified by:
    
    getValue in interface ManagedObjectValueAccess
    
    Parameters:
    
    instanceOID - the instance OID of the value. Thus, for scalar values with .0 suffix and for tabular objects with table index suffix.
    
    Returns:
    
    a copy of the requested Variable or null if such a variable does not exist.
  - setValue
```
public boolean setValue(org.snmp4j.smi.VariableBinding newValueAndInstancceOID)
```
    Description copied from interface: ManagedObjectValueAccess
    
    Sets the value of a particular MIB object instance managed by this ManagedObject. This is a low level operation, thus no change events will be fired.
    
    Specified by:
    
    setValue in interface ManagedObjectValueAccess
    
    Parameters:
    
    newValueAndInstancceOID - a VariableBinding identifying the object instance to modify by its OID and the new value by its variable part.
    
    Returns:
    
    true if the object instance exists and has been modified successfully, false otherwise.

Class MOScalar<V extends org.snmp4j.smi.Variable>

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

oid

access

Constructor Detail

MOScalar

MOScalar

Method Detail

getScope

getSingleInstanceScope

find

get

getAccess

checkRequestScope

next

isValueOK

prepare

commit

changeValue

undo

cleanup

getOid

getLowerBound

getUpperBound

isCovered

isLowerIncluded

isUpperIncluded

getValue

isVolatile

setValue

setVolatile

isOverlapping

addMOValueValidationListener

removeMOValueValidationListener

fireValidate

getID

load

save

covers

toString

toStringDetails

addMOChangeListener

removeMOChangeListener

fireBeforePrepareMOChange

fireAfterPrepareMOChange

fireBeforeMOChange

fireAfterMOChange

getValue

setValue