RelationSupport

java.lang.Object
- 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

Constructors

Constructor and Description
`RelationSupport(String relationId, ObjectName relationServiceName, MBeanServer relationServiceMBeanServer, String relationTypeName, RoleList list)` Creates a `RelationSupport` object.
`RelationSupport(String relationId, ObjectName relationServiceName, String relationTypeName, RoleList list)` Creates a `RelationSupport` object.

Method Summary

All Methods

Instance Methods

Concrete Methods
Modifier and Type	Method and Description
`RoleResult`	`getAllRoles()` Returns all roles present in the relation.
`Map<ObjectName,List<String>>`	`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<ObjectName>`	`getRole(String roleName)` Retrieves role value for given role name.
`Integer`	`getRoleCardinality(String roleName)` Returns the number of MBeans currently referenced in the given role.
`RoleResult`	`getRoles(String[] roleNameArray)` Retrieves values of roles with given names.
`void`	`handleMBeanUnregistration(ObjectName objectName, String roleName)` 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 flag)` Specifies whether this relation is handled by the Relation Service.
`void`	`setRole(Role role)` Sets the given role.
`RoleResult`	`setRoles(RoleList list)` 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 relationId,
                       ObjectName relationServiceName,
                       String relationTypeName,
                       RoleList list)
                throws InvalidRoleValueException,
                       IllegalArgumentException
```
    Creates a RelationSupport 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 whose class extends RelationSupport.
    
    Nothing is done at the Relation Service level, i.e. the RelationSupport object is not added to the RelationService and no checks are performed to see if the provided values are correct. The object is always created, EXCEPT if:
    
    - any of the required parameters is null.
    
    - the same name is used for two roles.
    
    To be handled as a relation, the RelationSupport object has to be added to the Relation Service using the Relation Service method addRelation().
    
    Parameters:
    
    relationId - relation identifier, to identify the relation in the Relation Service.
    Expected to be unique in the given Relation Service.
    
    relationServiceName - ObjectName of the Relation Service where the relation will be registered.
    This parameter is required as it is the Relation Service that is aware of the definition of the relation type of the given relation, so that will be able to check update operations (set).
    
    relationTypeName - Name of relation type.
    Expected to have been created in the given Relation Service.
    
    list - list of roles (Role objects) to initialize 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 any of the required parameters (relation id, relation service ObjectName, or relation type name) is null.
  - RelationSupport
```
public RelationSupport(String relationId,
                       ObjectName relationServiceName,
                       MBeanServer relationServiceMBeanServer,
                       String relationTypeName,
                       RoleList list)
                throws InvalidRoleValueException,
                       IllegalArgumentException
```
    Creates a RelationSupport 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 within the identified MBean Server.
    
    Nothing is done at the Relation Service level, i.e. the RelationSupport object is not added to the RelationService and no checks are performed to see if the provided values are correct. The object is always created, EXCEPT if:
    
    - any of the required parameters is null.
    
    - the same name is used for two roles.
    
    To be handled as a relation, the RelationSupport object has to be added to the Relation Service using the Relation Service method addRelation().
    
    Parameters:
    
    relationId - relation identifier, to identify the relation in the Relation Service.
    Expected to be unique in the given Relation Service.
    
    relationServiceName - ObjectName of the Relation Service where the relation will be registered.
    This parameter is required as it is the Relation Service that is aware of the definition of the relation type of the given relation, so that will be able to check update operations (set).
    
    relationServiceMBeanServer - 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.
    
    relationTypeName - Name of relation type.
    Expected to have been created in the given Relation Service.
    
    list - list of roles (Role objects) to initialize 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 any of the required parameters (relation id, relation service ObjectName, relation service MBeanServer, or relation type name) is null.
- Method Detail
  - getRole
```
public List<ObjectName> getRole(String roleName)
                         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:
    
    roleName - 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[] roleNameArray)
                    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:
    
    roleNameArray - 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 roleName)
                           throws IllegalArgumentException,
                                  RoleNotFoundException
```
    Returns the number of MBeans currently referenced in the given role.
    
    Specified by:
    
    getRoleCardinality in interface Relation
    
    Parameters:
    
    roleName - 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 role)
             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:
    
    role - role to be set (name and new value)
    
    Throws:
    
    IllegalArgumentException - if null role
    
    RoleNotFoundException - if there is no role with the supplied role's name or if the role is not writable (no test on the write access mode performed when initializing 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 list)
                    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:
    
    list - 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 list
    
    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 objectName,
                                      String roleName)
                               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:
    
    objectName - ObjectName of unregistered MBean
    
    roleName - 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<ObjectName,List<String>> 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.
    If the implementation of this method throws a RuntimeException or an Error, the MBean Server will rethrow those inside a RuntimeMBeanException or RuntimeErrorException, respectively. However, throwing an exception in postRegister will not change the state of the MBean: if the MBean was already registered (registrationDone is true), the MBean will remain registered.
    
    This might be confusing for the code calling createMBean() or registerMBean(), as such code might assume that MBean registration has failed when such an exception is raised. Therefore it is recommended that implementations of postRegister do not throw Runtime Exceptions or Errors if it can be avoided.
    
    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.
    If the implementation of this method throws a RuntimeException or an Error, the MBean Server will rethrow those inside a RuntimeMBeanException or RuntimeErrorException, respectively. However, throwing an exception in postDeregister will not change the state of the MBean: the MBean was already successfully deregistered and will remain so.
    
    This might be confusing for the code calling unregisterMBean(), as it might assume that MBean deregistration has failed. Therefore it is recommended that implementations of postDeregister do not throw Runtime Exceptions or Errors if it can be avoided.
  - 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 flag)
                                      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:
    
    flag - whether the relation is handled by the Relation Service.
    
    Throws:
    
    IllegalArgumentException - if null parameter

Class RelationSupport

Constructor Summary

Constructors

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

RelationSupport

RelationSupport

Method Detail

getRole

getRoles

getAllRoles

retrieveAllRoles

getRoleCardinality

setRole

setRoles

handleMBeanUnregistration

getReferencedMBeans

getRelationTypeName

getRelationServiceName

getRelationId

preRegister

postRegister

preDeregister

postDeregister

isInRelationService

setRelationServiceManagementFlag