System and method for dynamic exception handling using an external exception handler

• US 7,194,744 B2
• Filed: 12/17/2002
• Issued: 03/20/2007
• Est. Priority Date: 12/17/2002
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Nanavati, Amit A., Srivastava, Biplav, Bhide, Manish A, Kamesam, Pasumarti V, Batra, Vishal S
• Primary Examiner(s): NGUYEN, VAN H
• Application Number:
  US10/321,018
• Publication Number:
  US 20040117803A1
• Time in Patent Office: 1,554 Days
• Field of Search: 719/310, 719/318, 719330-332, 719/316, 714/37, 714/38, 714/48, 714/49, 712/200, 707/100, 717/107, 717/117, 717/137, 717/164
• US Class Current: 719/331
• CPC Class Codes: G06F 2209/481 Exception handling
• CPC Class Codes: G06F 9/3861 Recovery, e.g. branch miss-prediction, exception handling error detection or correction G06F11/00
• CPC Class Codes: G06F 9/4812 by interrupt, e.g. masked

Abstract

A method and a system for dynamically specifying exceptions and exception handlers for an application written in any computer language, which has exception handling facility, are described. The present decouples the exception handling logic from the application and thereby can be used to alter the behavior of the program/module/application as well as to define new types of exceptions at runtime. The decoupling of the exception handler logic eliminates the language dependence of the application and further helps in customizing the behavior of the application when they are being deployed in new environments. Moreover dynamic exception handling is not operating system dependent.

Claims

1. A method for enabling configurable dynamic exception handling absent support from an operating system and modification of programming language, said method comprising:

maintaining external exception handlers for desired exceptions, independent of modules raising the exceptions;

maintaining said external exception handlers in at least one exception handler repository;

updating said exception handler repository independent of an execution of said modules raising said exceptions; and

dynamically binding a selected external exception handler to each desired exception based on requirements of an application being serviced by the modules;

wherein the step of dynamically binding is enabled by providing exception handler specifications together with each exception handler, to map required exception handlers with the exceptions in the modules; and

wherein the modules are accessed by the application through an exception handler client wrapper that handles all application requests and processes required exceptions of the module using an exception handler code in said exception handler repository.

2. The method of claim 1, wherein the exception handler specifications determines each overriding exception, overridden exception in the modules, and accesses details of a corresponding handler code in said exception handler repository.

3. The method of claim 1, wherein the exception handler specifications are communicated to the application using a service layer.

4. The method of claim 1, wherein the nodule delegates handling of desired exceptions to an exception handler client that processes required exceptions, of a module using an exception handler code in said exception handler repository.

5. The method of claim 1, wherein the modules query an exception handler client for obtaining the exception handler specifications and processes required exceptions of the module using an exception handler code in said exception handler repository as determined by the exception handler specifications.

6. The method of claim 1, wherein an exception handler code is cached after it has been fetched from said exception handler repository.

7. The method of claim 1, wherein the exception handler repositoiy resides at any of a local location and a remote location.

8. The method of claim 1, wherein the exception handler and specifications of said exception handler are updated in the exception handler repository using at least one external application specific exception handler provider.

9. The method of claim 8, wherein new exception handlers are dynamically plugged in.

10. A system for enabling configurable dynamic exception handling absent support from an operating system and modification in programming language, said system comprising:

a first device operable for maintaining external exception handlers for desired exceptions, independent of modules raising the exceptions;

said first device comprising at least one exception handler repository wherein said first device is adapted to update said exception handler repository independently of an execution of the modules raising the exceptions; and

a second device operable for dynamically binding a selected external exception handler to each desired exception based on requirements of an application being serviced by the modules;

wherein said second device comprises exception handler specifications together with each exception handler, to map required exception handlers with the exceptions is the modules; and

wherein the modules are accessed by the application through an exception handler client wrapper that handles all application requests and processes required exceptions of the module using an exception handler code in said exception handler repository.

11. The system of claim 10, wherein the exception handler specifications determines each overriding exception, overridden exception in the modules, and accesses details of a corresponding handler code in said exception handler repository.

12. The system as claimed in claim 10, wherein the exception handler specifications are communicated to the application using a service layer that also acts as a platform for interaction between the various entities of the system.

13. The system of claim 12, wherein the service layer is centralized as a virtual machine including Java Virtual Machine (JVM) in which all the modules run locally.

14. The system of claim 13, wherein the virtual machine includes a functionality of an exception handler service client.

15. The system of claim 10, wherein the module delegates handling of desired exceptions to an exception handler client that processes required exceptions of a module using an exception handler code in said exception handler repository.

16. The system of claim 10, wherein the modules query an exception handler client for obtaining the exception handler specifications and processes required exceptions of the module using an exception handler code in said exception handler repository as determined by the exception handler specifications.

17. The system of claim 10, further comprising a unit operable to cache an exception handler code after it has been fetched from said exception handler repository.

18. The system of claim 10, wherein the exception handler repository resides at any of a local location and a remote location.

19. The system of claim 10, wherein the external exception handler is associated with logical names, wherein an exception handler service queries said logical names.

20. The system of claim 10, wherein the exception handler specifications are communicated to an exception handler service client using a markup language.

21. The system of claim 10, wherein the exception handler specifications are implemented as rules being stored in any of an exception handler service client and said exception handler repository.

22. The system of claim 21, wherein the exception handler service client comprises any of a rule execution engine and a specific rule execution engine, wherein said rule execution engine and specific rule execution engine are located at any of a local and remote location in communication with the exception handler service client.

23. The system of claim 10, wherein the modules are located within the application and the application includes exception handler specifications that are internally communicated to an exception handler service client.

24. The system of claim 10, wherein the application and the modules reside on a computing system, said computing system comprising:

a system bus;

a communications unit connected to the system bus;

a memory unit including a set of instructions connected to the system bus; and

a control unit executing the set of instructions in the memory unit.

25. The system of claim 10, wherein said system is connected to complementary systems, wherein said complementary systems comprise the modules to complement and supplement existing modules of said system.

26. A computer program product comprising computer readable program code stored on a computer readable storage medium embodied therein for performing a method for enabling configurable dynamic exception handling absent support from an operating system and absent support from a programming language, said method comprising:

maintaining external exception handlers for desired exceptions, independent of modules raising the exceptions;

maintaining said external exception handlers in at least one exception handler repository;

updating said exception handler repository independent of an execution of said modules raising said exceptions; and

dynamically binding a selected external exception handler to each desired exception based on requirements of an application being serviced by the modules;

wherein said step of dynamically binding comprises providing exception handler specifications together with each exception handler, to interface between required exception handlers and exception raising modules; and

wherein the modules are accessed by the application through an exception handler client wrapper that handles all application requests and processes required exceptions of the module using an exception handler code in said exception handler repository.