Information exchange operator for a tuplespace

• US 5,974,420 A
• Filed: 01/27/1998
• Issued: 10/26/1999
• Est. Priority Date: 01/27/1998
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: McLaughry, Stephen, Lehman, Tobin Jon
• Primary Examiner(s): HOMERE, JEAN RAYMOND
• Application Number:
  US09/013,505
• Time in Patent Office: 637 Days
• Field of Search: 707/2, 707/3, 707/4, 707/10, 707/101, 395/705, 395/200.33, 395/200.78, 395/200.79, 395/200.49, 395/800.07
• US Class Current: 1/1
• CPC Class Codes: G06F 9/544 Buffers; Shared memory; Pipes
• CPC Class Codes: G06F 9/546 Message passing systems or structures, e.g. queues
• CPC Class Codes: Y10S 707/99932 Access augmentation or optimizing
• CPC Class Codes: Y10S 707/99934 Query formulation, input preparation, or translation
• CPC Class Codes: Y10S 707/99942 Manipulating data structure, e.g. compression, compaction, compilation

Abstract

A method, apparatus, and article of manufacture for exchanging information in a computer-implemented database system. The present invention implements this exchange using a new operator known as a Rhonda operator. A Rhonda operator includes a tuple and template as arguments and, when performed, atomically swaps its tuple with a tuple from another Rhonda operator when both their templates match. More specifically, if two processes perform Rhonda operations, and each process'"'"' template argument matches the other process'"'"' tuple argument, then each process receives the other process'"'"' tuple as a result. This atomic synchronization can be performed for two or more Rhonda operators at a time.

Claims

1. A method of exchanging information in a computer-implemented database system, comprising the steps of:

(a) receiving a first operator having a first tuple and first template as arguments thereto and a second operator having a second tuple and second template as arguments thereto;

(b) determining whether the second tuple matches the first template and the first tuple matches the second template; and

(c) returning the second tuple as a result for the first operator and the first tuple as a result for the second operator when the second tuple matches the first template and the first tuple matches the second template.

2. The method of claim 1 above, wherein the results do not depend on an order of execution of the first and second operators.

3. The method of claim 1 above, further comprising the step of using a unique thread name to ensure correct operation of a handler for the first or second operators.

4. The method of claim 1 above, wherein:

(1) the step of receiving (a) further comprises the step of receiving a third operator having a third tuple and third template as arguments thereto;

(2) the step of determining (b) further comprises the step of determining whether the first tuple matches the second template, the second tuple matches the third template, and the third tuple matches the first template; and

(3) the step of returning (c) further comprises the step of returning the second tuple as a result for the first operator, the third tuple of as a result for the second operator, and the first tuple as a result for the third operator when the first tuple matches the second template, the second tuple matches the third template, and the third tuple matches the first template.

5. The method of claim 4 above, wherein the first, second, and third operators each have a group name as an argument thereto.

6. The method of claim 5 above, wherein the group name indicates that the results are not returned until all operators having the group name as an argument are satisfied.

7. The method of claim 5 above, wherein the first, second, and third operators each have a number as an argument thereto.

8. The method of claim 7 above, wherein the group name and counter indicates that the results are not returned until a count of operators having the group name as an argument equal to the number are satisfied.

9. The method of claim 1 above, further comprising the step of using a unique thread name to ensure correct operation of a handler for the first, second, or operators.

10. The method of claim 1 above, wherein:

(1) the step of receiving (a) further comprises the step of receiving a third operator having a third template and third tuple as arguments thereto;

(2) the step of determining (b) further comprises the step of determining whether the first tuple matches the third template, the second tuple matches the first template, and the third tuple matches the second template; and

(3) the step of returning (c) further comprises the step of returning the third tuple as a result for the first operator, the first tuple of as a result for the second operator, and the second tuple as a result for the third operator when the first tuple matches the third template, the second tuple matches the first template, and the third tuple matches the second template.

11. The method of claim 10 above, wherein the first, second, and third operators each have a group name as an argument thereto.

12. The method of claim 11 above, wherein the group name indicates that the results are not returned until all operators having the group name as an argument are satisfied.

13. The method of claim 11 above, wherein the first, second, and third operators each have a number as an argument thereto.

14. The method of claim 13 above, wherein the group name and counter indicates that the results are not returned until a count of operators having the group name as an argument equal to the number are satisfied.

15. The method of claim 10 above, further comprising the step of using a unique thread name to ensure correct operation of a handler for the first, second, or third operators.

16. A computer-implemented apparatus for exchanging information in a computer-implemented database system, comprising:

(a) a computer-implemented database system; and

(b) one or more instructions, performed by the system, for receiving a first operator having a first template and first tuple as arguments thereto and a second operator having a second template and second tuple as arguments thereto;

(c) one or more instructions, performed by the system, for determining whether the second tuple matches the first template and the first tuple matches the second template; and

(d) one or more instructions, performed by the system, for returning the second tuple as a result for the first operator and the first tuple as a result for the second operator when the second tuple matches the first template and the first tuple matches the second template.

17. An article of manufacture comprising a carrier tangibly embodying one or more instructions that when executed by a computer causes the computer to perform a method for exchanging information in a computer-implemented database system, the method comprising the steps of:

(a) receiving a first operator having a first template and first tuple as arguments thereto and a second operator having a second template and second tuple as arguments thereto;

(b) determining whether the second tuple matches the first template and the first tuple matches the second template; and

(c) returning the second tuple as a result for the first operator and the first tuple as a result for the second operator when the second tuple matches the first template and the first tuple matches the second template.