System and method for navigating beans using filters and container managed relationships

• US 20070038995A1
• Filed: 08/11/2005
• Published: 02/15/2007
• Est. Priority Date: 08/11/2005
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Sudarsan, Sridhar, Smithson, Martin, Boyle, Alan, Hambrick, Geoffrey
• Granted Patent: US 7,480,666 B2
• Time in Patent Office: Days
• US Class Current: 717/177
• CPC Class Codes: G06F 8/24 Object-oriented
• CPC Class Codes: G06F 8/34 Graphical or visual programming

Abstract

A system and method for navigating relationships between beans using filters and container managed relationships are provided. With the system and method, filters are specified in the relationship definition of a deployment descriptor of a bean. The filters generate additional predicates to the WHERE clauses in SQL SELECT statements generated based on the contents of the deployment descriptor. Moreover, these filters may be defined such that method parameters may be passed into the resulting deployed code to thereby make them more flexible. Therefore, with the system and method, rather than defining filters programmatically in methods of a bean'"'"'s implementation class, filters are defined declaratively in the deployment descriptor of the bean. Since these filters are specified in the deployment descriptor of the bean, they are accessible to clients of the bean through the local interface.

Claims

1. A method, in a data processing system, for deploying at least two beans, comprising:

defining a relationship between the at least two beans in a deployment descriptor;

defining, in the deployment descriptor, a filter on the relationship between the at least two beans; and

deploying the at least two beans based on the deployment descriptor, wherein at least one method is generated during deployment that implements the filter defined in the deployment descriptor.

2. The method of claim 1, wherein the beans are entity Enterprise Java Beans (EJBs) and the relationship is a Container Managed Relationship (CMR), and wherein the relationship is defined in the CMR definition of the deployment descriptor for the entity EJBs.

3. The method of claim 1, wherein defining a filter on the relationship comprises:

providing a filter tag in the deployment descriptor identifying a portion of the deployment descriptor as being associated with the filter; and

providing a filter definition in association with the filter tag, wherein the filter definition includes one or more attributes that are a subject of the filter.

4. The method of claim 3, wherein the filter definition further includes a designation of one or more parameters that may be passed into the filter to control the operation of the filter.

5. The method of claim 4, wherein the one or more parameters comprises a logical operator parameter identifying a logical operator parameter to be applied to one or more predicates generated based on the filter definition, and wherein the at least one method that implements the filter includes a query language statement having a WHERE clause, and wherein the one or more predicates are combined with the WHERE clause using the logical operator parameter.

6. The method of claim 1, wherein the at least one method that implements the filter includes a query language statement in which a WHERE clause of the query language statement is augmented to include one or more predicates generated based on the defined filter.

7. The method of claim 1, wherein deploying the beans based on the deployment descriptor comprises:

generating a query language statement based on the defined relationship;

interpreting the defined filter in the deployment descriptor to generate one or more predicates; and

applying the one or more predicates to the generated query language statement.

8. The method of claim 2, wherein the at least one method is an abstract method that may be called by EJB clients.

9. The method of claim 1, wherein the at least one method is a SELECT method.

10. The method of claim 7, wherein the query language statement is a Structured Query Language (SQL) SELECT statement.

11. A computer program product comprising a computer useable medium having a computer readable program, wherein the computer readable program, when executed on a computing device, causes the computing device to:

define a relationship between the at least two beans in a deployment descriptor;

define, in the deployment descriptor, a filter on the relationship between the at least two beans; and

deploy the at least two beans based on the deployment descriptor, wherein at least one method is generated during deployment that implements the filter defined in the deployment descriptor.

12. The computer program product of claim 11, wherein the beans are entity Enterprise Java Beans (EJBs) and the relationship is a Container Managed Relationship (CMR), and wherein the relationship is defined in the CMR definition of the deployment descriptor for the entity EJBs.

13. The computer program product of claim 11, wherein the computer readable program causes the computing device to define a filter on the relationship by:

providing a filter tag in the deployment descriptor identifying a portion of the deployment descriptor as being associated with the filter; and

providing a filter definition in association with the filter tag, wherein the filter definition includes one or more attributes that are a subject of the filter.

14. The computer program product of claim 13, wherein the filter definition further includes a designation of one or more parameters that may be passed into the filter to control the operation of the filter.

15. The computer program product of claim 14, wherein the one or more parameters comprises a logical operator parameter identifying a logical operator parameter to be applied to one or more predicates generated based on the filter definition, and wherein the at least one method that implements the filter includes a query language statement having a WHERE clause, and wherein the one or more predicates are combined with the WHERE clause using the logical operator parameter.

16. The computer program product of claim 11, wherein the at least one method that implements the filter includes a query language statement in which a WHERE clause of the query language statement is augmented to include one or more predicates generated based on the defined filter.

17. The computer program product of claim 11, wherein the computer readable program causes the computing device to deploy the beans based on the deployment descriptor by:

generating a query language statement based on the defined relationship;

interpreting the defined filter in the deployment descriptor to generate one or more predicates; and

applying the one or more predicates to the generated query language statement.

18. The computer program product of claim 12, wherein the at least one method is an abstract method that may be called by EJB clients.

19. The computer program product of claim 17, wherein the query language statement is a Structured Query Language (SQL) SELECT statement.

20. A system for deploying at least two beans, comprising:

a processor; and

a memory coupled to the processor, wherein the memory includes instructions executable by the processor to;

define a relationship between the at least two beans in a deployment descriptor;

define, in the deployment descriptor, a filter on the relationship between the at least two beans; and

deploy the at least two beans based on the deployment descriptor, wherein at least one method is generated during deployment that implements the filter defined in the deployment descriptor.