SYSTEM AND METHOD FOR UPDATING HARD-CODED DEPENDENCIES

• US 20120054727A1
• Filed: 08/30/2010
• Published: 03/01/2012
• Est. Priority Date: 08/30/2010
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Joukov, Nikolai A., Pfitzmann, Birgit M., Tarasov, Vasily, Ossher, Joel P.
• Granted Patent: US 8,949,812 B2
• Time in Patent Office: Days
• US Class Current: 717/168
• CPC Class Codes: G06F 9/44505 Configuring for program initiating, e.g. using registry, configuration files

Abstract

A system and method includes discovering one or more instances of external resource access by statically analyzing application code. One or more locations of constants are identified in the application code and a configuration repository that specify addresses of discovered instances of external resource access. The application code and the configuration repository are updated to change values of the constants to enable migration.

Claims

1. A method, comprising:

discovering one or more instances of external resource access by statically analyzing application code;

identifying one or more locations of constants in the application code and a configuration repository that specify addresses of discovered instances of external resource access; and

updating the application code and the configuration repository to change values of the constants to enable migration.

2. The method as recited in claim 1, wherein discovering includes:

collecting code and configuration information for a deployed application;

determining entrypoints in the deployed application;

constructing a call graph rooted at the entrypoints; and

detecting method invocations in the call graph that access external resources.

3. The method as recited in claim 1, wherein identifying includes identifying one or more locations of constants using string analysis.

4. The method as recited in claim 1, wherein identifying includes:

classifying locations of constants as positioned in the application code or in the configuration repository; and

for the locations in the configuration repository, resolving the location within the configuration files.

5. The method as recited in claim 1, wherein identifying includes reconstructing addresses of accessed external resources.

6. The method as recited in claim 5, wherein reconstructing includes reconstructing the addresses of the external resources by tracing back parameters of detected method invocations using string analysis.

7. The method as recited in claim 5, wherein updating further includes:

matching reconstructed addresses of the external resources with a table mapping old addresses to new addresses; and

updating the application code and the configuration repository to change values of the constants such that old addresses are replaced by new addresses.

8. The method as recited in claim 1, wherein updating includes creating a source code patch or a patch sketch to update an original source.

9. The method as recited in claim 1, wherein updating further includes:

automatically externalizing a constant in the application code to a file in the configuration repository;

synthesizing a new class including a static final field for each constant to be externalized;

creating a static initializer for the class that loads the configuration file and initializes each static final field to a value specified in the configuration file; and

replacing all associated load constant instructions with a corresponding field access instruction.

10. The method as recited in claim 1, wherein updating further includes:

providing an option to update the constants in the application code by performing at least one of;

modifying instructions in the application code to replace an old constant value with a new value; and

modifying instructions in the application code to replace the old constant value with a value loaded from synthesized configuration files in the configuration repository.

11. A computer readable storage medium comprising a computer readable program, wherein the computer readable program when executed on a computer causes the computer to perform the steps of:

discovering one or more instances of external resource access by statically analyzing application code;

identifying one or more locations of constants in the application code and a configuration repository that specify addresses of discovered instances of external resource access; and

updating the application code and the configuration repository to change values of the constants to enable migration.

12. The computer readable storage medium as recited in claim 11, wherein discovering includes:

collecting code and configuration information for a deployed application;

determining entrypoints in the deployed application;

constructing a call graph rooted at the entrypoints; and

detecting method invocations in the call graph that access external resources.

13. The computer readable storage medium as recited in claim 11, wherein identifying includes identifying one or more locations of constants using string analysis.

14. The computer readable storage medium as recited in claim 11, wherein identifying includes:

classifying locations of constants as positioned in the application code or in the configuration repository; and

for the locations in the configuration repository, resolving the location within the configuration files.

15. The computer readable storage medium as recited in claim 11, wherein identifying includes reconstructing addresses of accessed external resources.

16. The computer readable storage medium as recited in claim 15, wherein reconstructing includes reconstructing the addresses of the external resources by tracing back parameters of detected method invocations using string analysis.

17. The computer readable storage medium as recited in claim 15, wherein updating further includes:

matching reconstructed addresses of the external resources with a table mapping old addresses to new addresses; and

updating the application code and the configuration repository to change values of the constants such that old addresses are replaced by new addresses.

18. The computer readable storage medium as recited in claim 11, wherein updating includes creating a source code patch or a patch sketch to update an original source.

19. The computer readable storage medium as recited in claim 11, wherein updating further includes:

automatically externalizing a constant in the application code to a file in the configuration repository;

synthesizing a new class including a static final field for each constant to be externalized;

creating a static initializer for the class that loads the configuration file and initializes each static final field to a value specified in the configuration file; and

replacing all associated load constant instructions with a corresponding field access instruction.

20. The computer readable storage medium as recited in claim 11, wherein updating further includes:

providing an option to update the constants in the application code by performing at least one of;

modifying instructions in the application code to replace an old constant value with a new value; and

modifying instructions in the application code to replace the old constant value with a value loaded from synthesized configuration files in the configuration repository.

21. A system, comprising:

a processor;

a memory coupled to the processor and configured to execute a tool for changing hard-coded dependencies in a program'"'"'file, the tool configured to;

discover one or more instances of external resource access by statically analyzing application code;

identify one or more locations of constants in the application code and a configuration repository that specify addresses of discovered instances of external resource access; and

update the application code and the configuration repository to change values of the constants to enable migration.

22. The system as recited in claim 21, wherein the tool is configured to create a source code patch or a patch sketch so that an original source is able to be updated.

23. The system as recited in claim 21, wherein the tool updates the application codes by:

automatically externalizing a constant in the application code to a file in the configuration repository;

synthesizing a new class including a static final field for each constant to be externalized;

creating a static initializer for the class that loads the configuration file and initializes each static final field to a value specified in the configuration file; and

replacing all associated load constant instructions with a corresponding field access instruction.

24. The system as recited in claim 21, wherein the tool provided an option to update the constants in the application code by performing at least one of:

modifying instructions in the application code to replace an old constant value with a new value; and

modifying instructions in the application code to replace the old constant value with a value loaded from synthesized configuration files in the configuration repository.

25. The system as recited in claim 21, wherein the tool includes a string analysis program for analyzing the application code.