The Persistent State Control Adapter gives access to persistent state metadata directly from within a service (self context). The same data can be retrieved using the xUML Runtime API.

What a <<PersistentStateControl>> action does can be controlled via tagged value action. Currently the following actions are supported:

• listOwners
• getOwnerName
• listClasses
• getClassCounters
• getClassMetadata
• queryObjects
• deleteObject

Example File (Builder project Advanced Modeling/PState):

<your example path>\Advanced Modeling\PState\uml\pstatePurchaseOrder.xml

Listing all Persistent State Owners

In Load Balancing context, when e.g. running multiple Bridges, you can setup persistent state services to share persistent state objects. The persistent state objects are distinguished by an owner and owner id reflecting the actual service that owns these objects.
Prerequisite is that these services share the same persistent state database, see Load Balanced Persistent State for more details.

listOwners lists all owners that are maintaining persistent state objects of the current service.
For more information on how to manage ownership of persistent state objects, refer to Persistent State Ownership.

Parameters

Name	Type	Direction	Mandatory	Description
owners	Array of Owner	out		The adapter returns an array of owner details.

Getting the Name of an Owner

getOwnerName returns the name of the current owner (self).
For more information on how to manage ownership of persistent state objects, refer to Persistent State Ownership.

Parameters

Name	Type	Direction	Mandatory	Description
ownerName	String	out		The adapter returns the name of the current owner as a String.

Listing all Available Persistent State Classes

listClasses returns an array list of all available persistent state classes of the current service (self). By specifying includeObjectCount = true, you can get the actual object count per class.

Parameters

Name	Type	Direction	Mandatory	Description	Allowed Values
includeObjectCount	Boolean	in		Specify whether to include an object count per class to the response.	true	Include an object count per class.
					false	Do not include an object count per class (default).
classes	Array of ClassInfo	out		The adapter returns a list of classes as an Array of ClassInfo.

Getting Object Counters per Class

getClassCounters returns an array list of all available persistent state classes of the current service (self) and their actual counters. Refer to type ClassCounters for more details on which counters are available.

Parameters

Name	Type	Direction	Mandatory	Description
counters	Array of ClassCounters	out		The adapter returns the object counters per class as an Array. Refer to type ClassCounters for more details on the counters.

Getting the Persistent State Class Metadata

getClassMetadata returns the metadata of a given class. The action returns an array list of all attributes and their types.

Parameters

Name	Type	Direction	Mandatory	Description
class	String	in		Specify the name of the class to get metadata of. You can provide the value dynamically or via tagged value class on the adapter action.
classMetadata	ClassMetadata	out		The adapter returns a ClassMetadata object, listing all attributes and their metadata, and the primary and search keys. The array of primary keys is sorted in definition order.

Querying Persistent State Objects of a Given Class

With action queryObjects you can query the persistent state database for objects of a given class. Queries can use simple query conditions and complex query conditions (and/or).

Queries are steered by parameter selectQuery that, on the one hand, specifies global search data like searching by object dates and search order, and, on the other hand, can hold complex search queries.

Parameters

Name	Type	Direction	Mandatory	Description	Allowed Values
selectQuery	SelectObjectsQuery	in		Provide a search query.	.
includeObjectData	Boolean	in		Specify whether to include object data of the matching objects to the response.	true	Return object data of the found objects.
					false	Only return the objects metadata (default).
objectEntries	Array of ObjectEntry	out		The adapter returns an array of objects and some basic object metadata per object.

Attribute condition of type SelectObjectsQuery holds the custom search query itself. Attribute orderBy holds sorting specifications.

Building a Simple Query

By using only one condition of type SimpleQueryCondition you can build a simple query. Find below a the activity diagram of a simple query that returns all purchase orders with 2 or more open items.

selectQuery.conditions holds the query condition. It consists of

• name of the search key attribute to use for comparison
• an operator for the comparison
• a value to compare against

Valid operators are:

Building a Complex Query

Using type ComplexQueryCondition, you can build a complex query of multiple simple queries. They can be joined together by a disjunction (or) or a conjunction (and).

Assuming you have myCondition1 and myCondition2 of type SimpleQueryCondition, you can join them to an and query with an andQuery of type AndQueryCondition like:

create selectQuery;
create myCondition1;
create myCondition2;
create andQuery;

set selectQuery.sortByUpdate = "DESC";

set myCondition1.attribute = "openItems";
set myCondition1.operator = ">=";
set myCondition1.value = openItems;

set myCondition2.attribute = "customerID";
set myCondition2.operator = "=";
set myCondition2.value = "4711";

append myCondition1 to andQuery.condition;
append myCondition2 to andQuery.condition;

set selectQuery.condition = andQuery;

In this case, one of the to conditions could also be a complex condition instead of a simple one. Like that you can build very complex combinations of and and or queries.

Sorting the Query Results

You can sort the results that are returned by persistent state attributes and/or by persistent state meta data (creation timestamp and update timestamp).

Deleting Persistent State Objects

deleteObject deletes the object identified by class and objectId.

Parameters

Name	Type	Direction	Mandatory	Description	Example
class	String	in		Specify the name of the class to delete objects from.	PurchaseOrder
objectId	String	in		Specify the id of the object to delete.	000100058a79cb967f6e00000079

Parameter Types