Method for navigating beans using filters and container managed relationships

• US 7,480,666 B2
• Filed: 08/11/2005
• Issued: 01/20/2009
• Est. Priority Date: 08/11/2005
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Smithson, Martin J., Sudarsan, Sridhar, Boyle, Alan Iain, Hambrick, Geoffrey M.
• Primary Examiner(s): TRUONG, CAM Y T
• Application Number:
  US11/201,656
• Publication Number:
  US 20070038995A1
• Time in Patent Office: 1,258 Days
• Field of Search: 707/100
• US Class Current: 1/1
• CPC Class Codes: G06F 8/24 Object-oriented
• CPC Class Codes: G06F 8/34 Graphical or visual programming

Abstract

A method for navigating relationships between beans using filters and container managed relationships is provided. With the 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 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, wherein the defined filter includes one or more attributes that are a subject of the filter and wherein the filter, when executed, returns one or more beans having the one or more attributes, wherein the filter is defined declaratively in the deployment descriptor of a definition of the relationship, wherein defining the filter declaratively in the deployment descriptor allows the filter to be accessible to clients of the definition of the relationship through a local interface such that the filter is exposed on the local interface of the definition of the relationship, wherein exposing the filter on the local interface negates a generation of additional code to implement filters for each conceivable type of entity bean or group of entity beans requested by a client method and allows the client method to be navigated using the defined filter, and 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 further includes a designation of one or more parameters that may be passed into the filter to control the operation of the filter, 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; 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, 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.

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

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

5. The method of claim 1, wherein the query language statement is a Structured Query Language (SQL) SELECT statement.