APPARATUS FOR CONTROLLING SUBSCRIPTIONS

• US 20090187570A1
• Filed: 01/21/2009
• Published: 07/23/2009
• Est. Priority Date: 01/21/2008
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Siddall, Peter, Edwards, Ian Charles, Postlethwaite, David, Rumsey, Jonathan Lee
• Granted Patent: US 8,375,051 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/90344 by using string matching techniques

Abstract

An apparatus for controlling subscriptions comprising: a detector operable to detect to a subscription associated with a wildcard topic string; and an analyzer, responsive to the detection of the subscription associated with a wildcard topic string and a topic string of a topic node matching the wildcard topic string, for analyzing a first attribute of the topic node; and means for determining whether a subscriber associated with the subscription should receive a message associated with the topic string of the topic node.

Claims

1. An apparatus for controlling subscriptions, the apparatus comprising:

a processor with a detector operable to detect a subscription associated with a wildcard topic string; and

an analyzer, responsive to the detection of the subscription associated with the wildcard topic string and a topic string of a topic node matching the wildcard topic string, for analyzing a first attribute of the topic node,

wherein the analyzer determines whether a subscriber associated with the subscription should receive a message associated with the topic string of the topic node.

2. The apparatus of claim 1, wherein when the first attribute has a first value and the wildcard topic string is less specific than the topic string of the topic node, the analyzer is operable to determine that the subscriber should not receive a message associated with the topic string.

3. The apparatus of claim 2, wherein the analyzer is operable to determine that the subscriber should not receive a message associated with topic strings more specific than the associated topic string of the topic node.

4. The apparatus of claim 1, wherein when the first attribute has a first value and the wildcard topic string directly matches the topic string of the topic node, the analyzer is operable to determine that the subscriber should receive a message associated with the topic string.

5. The apparatus of claim 2, wherein when the first attribute has a second value and a parent node of the topic node comprises a first attribute having a first value and the wildcard topic string directly matches the topic string of the topic node, the analyzer is operable to determine that the subscriber should receive a message associated with the topic string.

6. The apparatus of claim 1, wherein the apparatus further comprises an attribute assignor operable to assign the first attribute to the topic node.

7. The apparatus of claim 6, wherein the assignor is operable to assign the first attribute in accordance with one or more assignment rules.

8. The apparatus of claim 1, wherein the analyzer is configured to add data associated with the subscriber to a linked list data structure associated with the topic node.

9. The apparatus of claim 1, wherein the detector is operable to detect a generation of a new topic node.

12. The method of claim 1, further comprising determining that the subscriber should not receive a message associated with topic strings more specific than the associated topic string of the topic node.

10. A method for controlling subscriptions, the method comprising:

detecting a subscription associated with a wildcard topic string;

analyzing, based on the detecting step and in response to a topic string of a topic node matching the wildcard topic string, a first attribute of a topic node by utilizing a processor; and

determining, based on the analyzing step, whether a subscriber associated with the subscription should receive a message associated with the topic string of the topic node.

11. The method of claim 10, further comprising when the first attribute has a first value and the wildcard topic string is less specific than the topic string of the topic node, determining that the subscriber should not receive a message associated with the topic string.

13. The method of claim 10, further comprising when the first attribute has a first value and the wildcard topic string directly matches the topic string of the topic node, determining that the subscriber should receive a message associated with the topic string.

14. The method of claim 11, further comprising when the first attribute has a second value and a parent node of the topic node comprises a first attribute having a first value and the wildcard topic string directly matches the topic string of the topic node, determining that the subscriber should receive a message associated with the topic string.

15. The method of claim 10, further comprising assigning the first attribute to the topic node.

16. The method of claim 15, wherein the assigning step is executed in accordance with one or more assignment rules.

17. The method of claim 10, further comprising adding data associated with the subscriber to a linked list data structure associated with the topic node.

18. The method of claim 10, further comprising detecting a generation of a new topic node.

19. A storage-medium containing a computer program comprising program code, which, when loaded in and executed by a computer causes the computer to perform the steps of:

detecting a subscription associated with a wildcard topic string;

analyzing, based on the detecting step and in response to a topic string of a topic node matching the wildcard topic string, a first attribute of a topic node; and

determining, based on the analyzing step, whether a subscriber associated with the subscription should receive a message associated with the topic string of the topic node.