System and method for improved clearing of JAVA object's variables

• US 7,827,212 B2
• Filed: 05/22/2003
• Issued: 11/02/2010
• Est. Priority Date: 05/22/2003
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Cotner, Curt Lee
• Primary Examiner(s): Lee; Wilson
• Assistant Examiner(s): Le; Michael
• Application Number:
  US10/444,676
• Publication Number:
  US 20040236712A1
• Time in Patent Office: 2,721 Days
• Field of Search: 707/206, 707/205, 707/813
• US Class Current: 707/813
• CPC Class Codes: G06F 9/4493 Object persistence

Abstract

An apparatus and a method of clearing a runtime data area where software objects store variables and each software object has a finalize method where the invention drives the finalize method of a software object when the finalize method of the software object has not performed an operation for a predetermined time period.

Claims

1. A method of clearing a runtime data area where a plurality of software objects store a variable and each of the plurality of software objects has a finalize method, comprising the steps of:

driving an initial finalize method of a first software object, the initial finalize method comprising a finalize method for the first software object that synchronizes clean-up activity for resources of the first software object;

clearing a runtime data area storing one or more variables associated with the first software object in response to the initial finalize method ending;

generating a finalize exception in response to the initial finalize method not performing an operation for a predetermined time period;

driving a next finalize method of a second software object in response to the generated finalize exception; and

marking the first software object as uncollectible in response to the initial finalize method being non-restartable.

2. The method of claim 1, further comprising the step of marking the first software object as uncollectible in response to the initial finalize method not performing an operation for the predetermined time period.

3. The method of claim 1, further comprising the steps of:

determining whether the initial finalize method is restartable in response to the initial finalize method not performing an operation for the predetermined time period; and

re-queuing the first software object for collection in response to the initial finalize method being restartable.

4. The method of claim 1, further comprising the steps of:

determining whether the initial finalize method is restartable in response to a finalize exception being generated; and

re-queuing the first software object for collection in response to the initial finalize method being restartable.

5. The method of claim 1, wherein driving the initial finalize method of the first software object further comprises the steps of:

determining whether the first software object is out of scope; and

driving the initial finalize method in response to determining that the first software object is out of scope.

6. The method of claim 1, wherein the first software object is a Java™

object.

7. A method of clearing a runtime data area where a plurality of software objects store a variable and each of the plurality of software objects has a finalize method, comprising the steps of:

driving a garbage collection method, the garbage collection method performing the steps of,

driving an initial finalize method of a first software object, the initial finalize method comprising a finalize method for the first software object that synchronizes clean-up activity for resources of the first software object;

clearing a runtime data area storing one or more variables associated with the first software object in response to the initial finalize method ending;

driving a next finalize method of a second software object in response to a generated finalize exception;

driving a finalize monitoring method, the finalize monitoring method performing the steps of,

determining when the initial finalize method has not performed an operation for the predetermined time period;

generating the finalize exception in response to the initial finalize method not performing an operation for a predetermined time period; and

marking the first software object as uncollectible in response to the initial finalize method being non-restartable.

8. The method of claim 7, the finalize monitoring method further comprising the step of marking the first software object as uncollectible in response to the initial finalize method not performing an operation for the predetermined time period.

9. The method of claim 7, the finalize monitoring method further comprising the steps of:

determining whether the initial finalize method is restartable in response to the initial finalize method not performing an operation for the predetermined time period; and

re-queuing the first software object for collection in response to the initial finalize method being restartable.

10. The method of claim 7, wherein driving the initial finalize method of the first software object comprises the steps of:

determining whether the first software object is out of scope; and

driving the initial finalize method in response to determining that the first software object is out of scope.

11. The method of claim 7, wherein the first software object is a Java™

object.

12. A computer readable medium encoded with data instruction for clearing a runtime data area where a plurality of software objects store a variable and each of the plurality of software objects has a finalize method, such that when executed by a device, the device is caused to perform processes comprising:

driving an initial finalize method of a first software object, the initial finalize method comprising a finalize method for the first software object that synchronizes clean-up activity for resources of the first software object;

clearing a runtime data area storing one or more variables associated with the first software object in response to the initial finalize method ending;

generating a finalize exception in response to the initial finalize method not performing an operation for a predetermined time period;

driving a next finalize method of a second software object in response to the generated finalize exception; and

marking the first software object as uncollectible in response to the initial finalize method being non-restartable.

13. A computer readable medium encoded with data instruction for clearing a runtime data area where a plurality of software objects store a variable and each of the plurality of software objects has a finalize method of claim 12, wherein the device is further caused to perform the step of marking the first software object as uncollectible when the initial finalize method has not performed an operation for the predetermined time period.

14. A computer readable medium encoded with data instruction for clearing a runtime data area where a plurality of software objects store a variable and each of the plurality of software objects has a finalize method of claim 12, wherein the device is further caused to perform the steps of:

determining whether the initial finalize method is restartable in response to the initial finalize method not performing an operation for the predetermined time period; and

re-queuing the first software object for collection in response to the initial finalize method being restartable.

15. A computer readable medium encoded with data instruction for clearing a runtime data area where a plurality of software objects store a variable and each of the plurality of software objects has a finalize method of claim 12, wherein the device is further caused to perform the steps of:

determining whether the initial finalize method is restartable in response to a finalize exception being generated; and

re-queuing the first software object for collection in response to the initial finalize method being restartable.

16. A computer readable medium encoded with data instruction for clearing a runtime data area where a plurality of software objects store a variable and each of the plurality of software objects has a finalize method of claim 12, wherein driving the initial finalize method of the first software object comprises the steps of:

determining whether the first software object is out of scope; and

driving the initial finalize method in response to determining that the first software object is out of scope.

17. A computer readable medium encoded with data instruction for clearing a runtime data area where a plurality of software objects store a variable and each of the plurality of software objects has a finalize method of claim 12, wherein the first software object is a Java™

object.

18. An apparatus for clearing a runtime data area where a plurality of software objects store a variable and each of the plurality of software objects has a finalize method, comprising:

means for driving an initial finalize method of a first software object, the initial finalize method comprising a finalize method for the first software object that synchronizes clean-up activity for resources of the first software object;

means for clearing a runtime data area storing one or more variables associated with the first software object in response to the initial finalize method ending;

means for generating a finalize exception in response to the initial finalize method not performing an operation for a predetermined time period;

means for driving a next finalize method of a second software object in response to the generated finalize exception; and

marking the first software object as uncollectible in response to the initial finalize method being non-restartable.

19. The apparatus of claim 18, further comprising means for marking the first software objects as uncollectible when the initial finalize method has not performed an operation for the predetermined time period.

20. The apparatus of claim 18, further comprising:

means for determining whether the initial finalize method is restartable in response to the initial finalize method not performing an operation for the predetermined time period;

means for re-queuing the first software object for collection in response to the initial finalize method being restartable.

21. The apparatus of claim 18, further comprising:

means for determining whether the initial finalize method is restartable in response to a finalize exception being generated;

means for re-queuing the first software object for collection in response to the initial finalize method being restartable.

22. The apparatus of claim 18, wherein the means for driving the initial finalize method of the first software object comprises:

means for determining whether the first software object is out of scope; and

means for driving the initial finalize method in response to determining that the first software object is out of scope.

23. The apparatus of claim 18, wherein the first software object is a Java™

object.