JavaTM 2 Platform
Standard Ed. 5.0

javax.management.relation
Class RelationSupport

java.lang.Object
  extended by javax.management.relation.RelationSupport
All Implemented Interfaces:
MBeanRegistration, Relation, RelationSupportMBean

public class RelationSupport
extends 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.

Since:
1.5

Constructor Summary
RelationSupport(String theRelId, ObjectName theRelServiceName, MBeanServer theRelServiceMBeanServer, String theRelTypeName, RoleList theRoleList)
          Creates object.
RelationSupport(String theRelId, ObjectName theRelServiceName, String theRelTypeName, RoleList theRoleList)
          Creates object.
 
Method Summary
 RoleResult getAllRoles()
          Returns all roles present in the relation.
 Map getReferencedMBeans()
          Retrieves MBeans referenced in the various roles of the relation.
 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.
 String getRelationTypeName()
          Returns name of associated relation type.
 List getRole(String theRoleName)
          Retrieves role value for given role name.
 Integer getRoleCardinality(String theRoleName)
          Returns the number of MBeans currently referenced in the given role.
 RoleResult getRoles(String[] theRoleNameArray)
          Retrieves values of roles with given names.
 void handleMBeanUnregistration(ObjectName theObjName, String theRoleName)
          Callback used by the Relation Service when a MBean referenced in a role is unregistered.
 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 unregistered in the MBean server.
 void postRegister(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 unregistered 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(Boolean theFlg)
          Specifies whether this relation is handled 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(String theRelId,
                       ObjectName theRelServiceName,
                       String theRelTypeName,
                       RoleList theRoleList)
                throws InvalidRoleValueException,
                       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.

Expected to conform to relation info in associated relation type.

Throws:
InvalidRoleValueException - if the same name is used for two roles.
IllegalArgumentException - if a required value (Relation Service Object Name, etc.) is not provided as parameter.

RelationSupport

public RelationSupport(String theRelId,
                       ObjectName theRelServiceName,
                       MBeanServer theRelServiceMBeanServer,
                       String theRelTypeName,
                       RoleList theRoleList)
                throws InvalidRoleValueException,
                       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 required 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 the 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.

Expected to be the MBean Server where the Relation Service 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.

Expected to conform to relation info in associated relation type.

Throws:
InvalidRoleValueException - if the same name is used for two roles.
IllegalArgumentException - if a required value (Relation Service Object Name, etc.) is not provided as parameter.
Method Detail

getRole

public List getRole(String theRoleName)
             throws IllegalArgumentException,
                    RoleNotFoundException,
                    RelationServiceNotRegisteredException
Retrieves role value for given role name.

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

Specified by:
getRole in interface Relation
Parameters:
theRoleName - name of role
Returns:
the ArrayList of ObjectName objects being the role value
Throws:
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
See Also:
setRole(javax.management.relation.Role)

getRoles

public RoleResult getRoles(String[] theRoleNameArray)
                    throws IllegalArgumentException,
                           RelationServiceNotRegisteredException
Retrieves values of roles with given names.

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

Specified by:
getRoles in interface Relation
Parameters:
theRoleNameArray - array of names of roles to be retrieved
Returns:
a RoleResult object, including a RoleList (for roles successfully retrieved) and a RoleUnresolvedList (for roles not retrieved).
Throws:
IllegalArgumentException - if null role name
RelationServiceNotRegisteredException - if the Relation Service is not registered in the MBean Server
See Also:
setRoles(javax.management.relation.RoleList)

getAllRoles

public RoleResult getAllRoles()
                       throws RelationServiceNotRegisteredException
Returns all roles present in the relation.

Specified by:
getAllRoles in interface Relation
Returns:
a RoleResult object, including a RoleList (for roles successfully retrieved) and a RoleUnresolvedList (for roles not readable).
Throws:
RelationServiceNotRegisteredException - if the Relation Service is not registered in the MBean Server

retrieveAllRoles

public RoleList retrieveAllRoles()
Returns all roles in the relation without checking read mode.

Specified by:
retrieveAllRoles in interface Relation
Returns:
a RoleList

getRoleCardinality

public Integer getRoleCardinality(String theRoleName)
                           throws IllegalArgumentException,
                                  RoleNotFoundException
Returns the number of MBeans currently referenced in the given role.

Specified by:
getRoleCardinality in interface Relation
Parameters:
theRoleName - name of role
Returns:
the number of currently referenced MBeans in that role
Throws:
IllegalArgumentException - if null role name
RoleNotFoundException - if there is no role with given name

setRole

public void setRole(Role theRole)
             throws 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).

Specified by:
setRole in interface Relation
Parameters:
theRole - role to be set (name and new value)
Throws:
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.
See Also:
getRole(java.lang.String)

setRoles

public RoleResult setRoles(RoleList theRoleList)
                    throws 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 one notification (RelationNotification with type RELATION_BASIC_UPDATE or RELATION_MBEAN_UPDATE, depending if the relation is a MBean or not) per updated role.

Specified by:
setRoles in interface Relation
Parameters:
theRoleList - list of roles to be set
Returns:
a RoleResult object, including a RoleList (for roles successfully set) and a RoleUnresolvedList (for roles not set).
Throws:
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.
See Also:
getRoles(java.lang.String[])

handleMBeanUnregistration

public void handleMBeanUnregistration(ObjectName theObjName,
                                      String theRoleName)
                               throws 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.

Specified by:
handleMBeanUnregistration in interface Relation
Parameters:
theObjName - ObjectName of unregistered MBean
theRoleName - name of role where the MBean is referenced
Throws:
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 Map getReferencedMBeans()
Retrieves MBeans referenced in the various roles of the relation.

Specified by:
getReferencedMBeans in interface Relation
Returns:
a HashMap mapping:

ObjectName -> ArrayList of String (role names)


getRelationTypeName

public String getRelationTypeName()
Returns name of associated relation type.

Specified by:
getRelationTypeName in interface Relation
Returns:
the name of the relation type.

getRelationServiceName

public ObjectName getRelationServiceName()
Returns ObjectName of the Relation Service handling the relation.

Specified by:
getRelationServiceName in interface Relation
Returns:
the ObjectName of the Relation Service.

getRelationId

public String getRelationId()
Returns relation identifier (used to uniquely identify the relation inside the Relation Service).

Specified by:
getRelationId in interface Relation
Returns:
the relation id.

preRegister

public ObjectName preRegister(MBeanServer server,
                              ObjectName name)
                       throws 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
Parameters:
server - The MBean server in which the MBean will be registered.
name - The object name of the MBean. This name is null if the name parameter to one of the createMBean or registerMBean methods in the MBeanServer interface is null. In that case, this method must return a non-null ObjectName for the new MBean.
Returns:
The name under which the MBean is to be registered. This value must not be null. If the name parameter is not null, it will usually but not necessarily be the returned value.
Throws:
Exception - This exception will be caught by the MBean server and re-thrown as an MBeanRegistrationException.

postRegister

public void postRegister(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
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 Exception
Description copied from interface: MBeanRegistration
Allows the MBean to perform any operations it needs before being unregistered by the MBean server.

Specified by:
preDeregister in interface MBeanRegistration
Throws:
Exception - This exception will 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 unregistered in the MBean server.

Specified by:
postDeregister in interface MBeanRegistration

isInRelationService

public Boolean isInRelationService()
Returns an internal flag specifying if the object is still handled by the Relation Service.

Specified by:
isInRelationService in interface RelationSupportMBean
Returns:
a Boolean equal to Boolean.TRUE if the object is still handled by the Relation Service and Boolean.FALSE otherwise.

setRelationServiceManagementFlag

public void setRelationServiceManagementFlag(Boolean theFlg)
                                      throws IllegalArgumentException
Description copied from interface: RelationSupportMBean

Specifies whether this relation is handled by the Relation Service.

BEWARE, this method has to be exposed 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
Parameters:
theFlg - whether the relation is handled by the Relation Service.
Throws:
IllegalArgumentException - if null parameter

JavaTM 2 Platform
Standard Ed. 5.0

Submit a bug or feature
For further API reference and developer documentation, see Java 2 SDK SE Developer Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.

Copyright 2004 Sun Microsystems, Inc. All rights reserved. Use is subject to license terms. Also see the documentation redistribution policy.