javax.management.relation
Class RelationSupport

java.lang.Object
  |
  +--javax.management.relation.RelationSupport

public class RelationSupport

extends java.lang.Object

implements RelationSupportMBean, MBeanRegistration

A RelationSupport object is used internally by the Relation Service to represent simple relations (only roles, no properties or methods), with an unlimited number of roles, of any relation type. As internal representation, it is not exposed to the user.

RelationSupport class conforms to the design patterns of standard MBean. So the user can decide to instantiate a RelationSupport object himself as a MBean (as it follows the MBean design patterns), to register it in the MBean Server, and then to add it in the Relation Service.

The user can also, when creating his own MBean relation class, have it extending RelationSupport, to retrieve the implementations of required interfaces (see below).

It is also possible to have in a user relation MBean class a member being a RelationSupport object, and to implement the required interfaces by delegating all to this member.

RelationSupport implements the Relation interface (to be handled by the Relation Service).

It implements also the MBeanRegistration interface to be able to retrieve the MBean Server where it is registered (if registered as a MBean) to access to its Relation Service.

Version:

1.7

Author:

Maurizio Simeoni

Constructor Summary

RelationSupport(java.lang.String theRelId, ObjectName theRelServiceName, MBeanServer theRelServiceMBeanServer, java.lang.String theRelTypeName, RoleList theRoleList)
Creates object.

RelationSupport(java.lang.String theRelId, ObjectName theRelServiceName, java.lang.String theRelTypeName, RoleList theRoleList)
Creates object.

Method Summary

RoleResult	getAllRoles() Returns all roles present in the relation .
java.util.Map	getReferencedMBeans() Retrieves MBeans referenced in the various roles of the relation.
java.lang.String	getRelationId() Returns relation identifier (used to uniquely identify the relation inside the Relation Service)
ObjectName	getRelationServiceName() Returns ObjectName of the Relation Service handling the relation
java.lang.String	getRelationTypeName() Returns name of associated relation type.
java.util.List	getRole(java.lang.String theRoleName) Retrieves role value for given role name.
java.lang.Integer	getRoleCardinality(java.lang.String theRoleName) Returns the number of MBeans currently referenced in the given role.
RoleResult	getRoles(java.lang.String[] theRoleNameArray) Retrieves values of roles with given names
void	handleMBeanUnregistration(ObjectName theObjName, java.lang.String theRoleName) Callback used by the Relation Service when a MBean referenced in a role is unregistered.
java.lang.Boolean	isInRelationService() Returns an internal flag specifying if the object is still handled by the Relation Service.
void	postDeregister() Allows the MBean to perform any operations needed after having been de-registered in the MBean server.
void	postRegister(java.lang.Boolean registrationDone) Allows the MBean to perform any operations needed after having been registered in the MBean server or after the registration has failed.
void	preDeregister() Allows the MBean to perform any operations it needs before being de-registered by the MBean server.
ObjectName	preRegister(MBeanServer server, ObjectName name) Allows the MBean to perform any operations it needs before being registered in the MBean server.
RoleList	retrieveAllRoles() Returns all roles in the relation without checking read mode.
void	setRelationServiceManagementFlag(java.lang.Boolean theFlg) Sets the flag to specify that it is handled or not by the Relation Service
void	setRole(Role theRole) Sets the given role.
RoleResult	setRoles(RoleList theRoleList) Sets the given roles.

Methods inherited from class java.lang.Object

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

Constructor Detail

RelationSupport

public RelationSupport(java.lang.String theRelId,
                       ObjectName theRelServiceName,
                       java.lang.String theRelTypeName,
                       RoleList theRoleList)
                throws InvalidRoleValueException,
                       java.lang.IllegalArgumentException

Creates object.

This constructor has to be used when the RelationSupport object will be registered as a MBean by the user, or when creating a user relation MBean those class extends RelationSupport.

Nothing is done at the Relation Service level, i.e. the RelationSupport object is not added, and no check if the provided values are correct. The object is always created, EXCEPT if:

-one mandatory parameter is not provided;

-the same name is used for two roles.

To be handled as a relation, the object has then to be added in the Relation Service using Relation Service method addRelation().

Parameters:

theRelId - Relation identifier, to identify the relation in the Relation Service.Expected to be unique in the given Relation Service.

theRelServiceName - ObjectName of the Relation Service where the relation will be registered.It is required as this is the Relation Service that is aware of the definition of the relation type of given relation, so that will be able to check update operations (set).

theRelTypeName - Name of relation type. Expected to have been created in given Relation Service.

theRoleList - List of roles (Role objects) to initialised the relation. Can be null.

Throws:

InvalidRoleValueException - if the same name is used for two roles.

java.lang.IllegalArgumentException - if a required value (Relation Service Object Name, etc.) is not provided as parameter.

RelationSupport

public RelationSupport(java.lang.String theRelId,
                       ObjectName theRelServiceName,
                       MBeanServer theRelServiceMBeanServer,
                       java.lang.String theRelTypeName,
                       RoleList theRoleList)
                throws InvalidRoleValueException,
                       java.lang.IllegalArgumentException

Creates object.

This constructor has to be used when the user relation MBean implements the interfaces expected to be supported by a relation by delegating to a RelationSupport object.

This object needs to know the Relation Service expected to handle the relation. So it has to know the MBean Server where the Relation Service is registered.

According to a limitation, a relation MBean must be registered in the same MBean Server as the Relation Service expected to handle it. So the user relation MBean has to be created and registered, and then the wrapped RelationSupport object can be created with identified MBean Server.

Nothing is done at the Relation Service level, i.e. the RelationSupport object is not added, and no check if the provided values are correct. The object is always created, EXCEPT if:

-one mandatory parameter is not provided;

-the same name is used for two roles.

To be handled as a relation, the object has then to be added in the Relation Service using Relation Service method addRelation().

Parameters:

theRelId - Relation identifier, to identify the relation in the Relation Service.Expected to be unique in the given Relation Service.

theRelServiceName - ObjectName of the Relation Service where the relation will be registered.It is required as this is the Relation Service that is aware of the definition of the relation type of given relation, so that will be able to check update operations (set).

theRelServiceMBeanServer - MBean Server where the wrapping MBean is or will be registered.

theRelTypeName - Name of relation type.

Expected to have been created in given Relation Service.

theRoleList - List of roles (Role objects) to initialised the relation. Can be null.

Throws:

InvalidRoleValueException - if the same name is used for two roles.

java.lang.IllegalArgumentException - if a required value (Relation Service Object Name, etc.) is not provided as parameter.

Method Detail

getAllRoles

public RoleResult getAllRoles()
                       throws RelationServiceNotRegisteredException

Returns all roles present in the relation .

Returns:

a RoleResult object, including a RoleList (for roles succcessfully retrieved) and a RoleUnresolvedList (for roles not readable).

Throws:

RelationServiceNotRegisteredException - if the Relation Service is not registered in the MBean Server.

getRole

public java.util.List getRole(java.lang.String theRoleName)
                       throws java.lang.IllegalArgumentException,
                              RoleNotFoundException,
                              RelationServiceNotRegisteredException

Retrieves role value for given role name.

Checks if the role exists and is readable according to the relation type.

Parameters:

theRoleName - name of role

Returns:

the ArrayList of ObjectName objects being the role value

Throws:

java.lang.IllegalArgumentException - if null role name

RoleNotFoundException - if:

-there is no role with given name;

-the role is not readable.

RelationServiceNotRegisteredException - if the Relation Service is not registered in the MBean Server.

getRoles

public RoleResult getRoles(java.lang.String[] theRoleNameArray)
                    throws java.lang.IllegalArgumentException,
                           RelationServiceNotRegisteredException

Retrieves values of roles with given names

Checks for each role if it exists and is readable according to the relation type.

Parameters:

theRoleNameArray - array of names of roles to be retrieved

Returns:

a RoleResult object, including a RoleList (for roles succcessfully retrieved) and a RoleUnresolvedList (for roles not retrieved).

Throws:

java.lang.IllegalArgumentException - if null role name

RelationServiceNotRegisteredException - if the Relation Service is not registered in the MBean Server.

getRoleCardinality

public java.lang.Integer getRoleCardinality(java.lang.String theRoleName)
                                     throws java.lang.IllegalArgumentException,
                                            RoleNotFoundException

Returns the number of MBeans currently referenced in the given role.

Parameters:

theRoleName - name of role

Returns:

the number of currently referenced MBeans in that role

Throws:

java.lang.IllegalArgumentException - if null role name

RoleNotFoundException - if there is no role with given name

retrieveAllRoles

public RoleList retrieveAllRoles()

Returns all roles in the relation without checking read mode.

Returns:

a RoleList

setRole

public void setRole(Role theRole)
             throws java.lang.IllegalArgumentException,
                    RoleNotFoundException,
                    RelationTypeNotFoundException,
                    InvalidRoleValueException,
                    RelationServiceNotRegisteredException,
                    RelationNotFoundException

Sets the given role.

Will check the role according to its corresponding role definition provided in relation's relation type.

Will send a notification (RelationNotification with type RELATION_BASIC_UPDATE or RELATION_MBEAN_UPDATE, depending if the relation is a MBean or not).

Parameters:

theRole - role to be set (name and new value).

Throws:

java.lang.IllegalArgumentException - if null role

RoleNotFoundException - if the role is not writable (no test on the write access mode performed when initialising the role).

InvalidRoleValueException - if value provided for role is not valid, i.e.:

-the number of referenced MBeans in given value is less than expected minimum degree;

-the number of referenced MBeans in provided value exceeds expected maximum degree;

-one referenced MBean in the value is not an Object of the MBean class expected for that role ;

-a MBean provided for that role does not exist.

RelationServiceNotRegisteredException - if the Relation Service is not registered in the MBean Server.

RelationTypeNotFoundException - if the relation type has not been declared in the Relation Service.

RelationNotFoundException - if the relation has not been added in the Relation Service.

setRoles

public RoleResult setRoles(RoleList theRoleList)
                    throws java.lang.IllegalArgumentException,
                           RelationServiceNotRegisteredException,
                           RelationTypeNotFoundException,
                           RelationNotFoundException

Sets the given roles.

Will check the role according to its corresponding role definition provided in relation's relation type.

Will send a notification (RelationNotification with type RELATION_BASIC_UPDATE or RELATION_MBEAN_UPDATE, depending if the relation is a MBean or not).

Parameters:

theRoleList - list of roles to be set

Returns:

a RoleResult object, including a RoleList (for roles succcessfully set) and a RoleUnresolvedList (for roles not set).

Throws:

java.lang.IllegalArgumentException - if null role name

RelationServiceNotRegisteredException - if the Relation Service is not registered in the MBean Server.

RelationTypeNotFoundException - if the relation type has not been declared in the Relation Service.

RelationNotFoundException - if the relation MBean has not been added in the Relation Service.

handleMBeanUnregistration

public void handleMBeanUnregistration(ObjectName theObjName,
                                      java.lang.String theRoleName)
                               throws java.lang.IllegalArgumentException,
                                      RoleNotFoundException,
                                      InvalidRoleValueException,
                                      RelationServiceNotRegisteredException,
                                      RelationTypeNotFoundException,
                                      RelationNotFoundException

Callback used by the Relation Service when a MBean referenced in a role is unregistered.

The Relation Service will call this method to let the relation take action to reflect the impact of such unregistration.

BEWARE. the user is not expected to call this method.

Current implementation is to set the role with its current value (list of ObjectNames of referenced MBeans) without the unregistered one.

Parameters:

theObjName - ObjectName of unregistered MBean

theRoleName - name of role where the MBean is referenced

Throws:

java.lang.IllegalArgumentException - if null parameter

RoleNotFoundException - if role does not exist in the relation or is not writable.

InvalidRoleValueException - if role value does not conform to the associated role info (this will never happen when called from the Relation Service).

RelationServiceNotRegisteredException - if the Relation Service is not registered in the MBean Server.

RelationTypeNotFoundException - if the relation type has not been declared in the Relation Service.

RelationNotFoundException - if this method is called for a relation MBean not added in the Relation Service.

getReferencedMBeans

public java.util.Map getReferencedMBeans()

Retrieves MBeans referenced in the various roles of the relation.

Returns:

a HashMap mapping:ObjectName -> ArrayList of String (role names)

getRelationTypeName

public java.lang.String getRelationTypeName()

Returns name of associated relation type.

getRelationServiceName

public ObjectName getRelationServiceName()

Returns ObjectName of the Relation Service handling the relation

getRelationId

public java.lang.String getRelationId()

Returns relation identifier (used to uniquely identify the relation inside the Relation Service)

isInRelationService

public java.lang.Boolean isInRelationService()

Returns an internal flag specifying if the object is still handled by the Relation Service.

Specified by:

isInRelationService in interface RelationSupportMBean

setRelationServiceManagementFlag

public void setRelationServiceManagementFlag(java.lang.Boolean theFlg)
                                      throws java.lang.IllegalArgumentException

Sets the flag to specify that it is handled or not by the Relation Service

BEWARE, this method has to be exposed for the user relation MBeans, as the Relation Service will access the relation through its management interface. It is RECOMMENDED NOT to use this method. Using it does not affect the registration of the relation object in the Relation Service, but will provide wrong information about it!!!!

Specified by:

setRelationServiceManagementFlag in interface RelationSupportMBean

Throws:

java.lang.IllegalArgumentException - if null parameter

preRegister

public ObjectName preRegister(MBeanServer server,
                              ObjectName name)
                       throws java.lang.Exception

Description copied from interface: MBeanRegistration

Allows the MBean to perform any operations it needs before being registered in the MBean server. If the name of the MBean is not specified, the MBean can provide a name for its registration. If any exception is raised, the MBean will not be registered in the MBean server.

Specified by:

preRegister in interface MBeanRegistration

Tags copied from interface: MBeanRegistration

Parameters:

server - The MBean server in which the MBean will be registered.

name - The object name of the MBean

Returns:

The name of the MBean registered.

Throws:

java.lang.Exception - This exception should be caught by the MBean server and re-thrown as an MBeanRegistrationException .

postRegister

public void postRegister(java.lang.Boolean registrationDone)

Description copied from interface: MBeanRegistration

Allows the MBean to perform any operations needed after having been registered in the MBean server or after the registration has failed.

Specified by:

postRegister in interface MBeanRegistration

Tags copied from interface: MBeanRegistration

Parameters:

registrationDone - Indicates whether or not the MBean has been successfully registered in the MBean server. The value false means that the registration phase has failed.

preDeregister

public void preDeregister()
                   throws java.lang.Exception

Description copied from interface: MBeanRegistration

Allows the MBean to perform any operations it needs before being de-registered by the MBean server.

Specified by:

preDeregister in interface MBeanRegistration

Tags copied from interface: MBeanRegistration

Throws:

java.lang.Exception - This exception should be caught by the MBean server and re-thrown as an MBeanRegistrationException

postDeregister

public void postDeregister()

Description copied from interface: MBeanRegistration

Allows the MBean to perform any operations needed after having been de-registered in the MBean server.

Specified by:

postDeregister in interface MBeanRegistration