System and method for updating hard-coded dependencies

• US 8,949,812 B2
• Filed: 08/30/2010
• Issued: 02/03/2015
• 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., Ossher, Joel P., Pfitzmann, Birgit M., Tarasov, Vasily
• Primary Examiner(s): Ravetti, Dante
• Application Number:
  US12/871,468
• Publication Number:
  US 20120054727A1
• Time in Patent Office: 1,618 Days
• Field of Search: 717/168, 705/16, 705/21, 705/59, 705/71, 380/44, 380/262, 380/278, 380/279
• 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, by a processor, one or more instances of external resource access by statically analyzing application code;

specifying, by the processor, addresses of the discovered instances of external resource access;

identifying, by the processor, one or more addresses of one or more constants in the application code and a configuration repository of the specified addresses of discovered instances of external resource access, the one or more constants being stored in a non-transitory computer readable storage medium;

updating, by the processor, one or more values of the one or more constants in the application code and the configuration repository;

wherein the application code is updated by replacing at least one of the one or more values of the one or more constants with one or more updated values of the one or more constants; and

wherein the updating includes matching one or more addresses of the external resources with a table mapping the one or more addresses of the one or more constants to one or more updated constant addresses; and

using, by the processor, the one or more updated values of the one or more constants in the application code and the configuration repository in current or future migrations.

2. The method as recited in claim 1, wherein the discovering one or more instances of external resource access includes:

collecting code and configuration information for a deployed application;

determining entry points in the deployed application;

constructing a call graph rooted at the entry points; 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 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 one or more 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 one or more 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 non-transitory 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;

specifying addresses of the discovered instances of external resource access;

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

updating one or more values of the one or more constants in the application code and the configuration repository;

wherein the application code is updated by replacing at least one of the one or more values of the one or more constants with one or more updated values of the one or more constants; and

wherein the updating includes matching one or more addresses of the external resources with a table mapping the one or more addresses of the one or more constants to one or more updated constant addresses; and

using the one or more updated values of the one or more constants in the application code and the configuration repository in current or future migrations.

12. The computer readable storage medium as recited in claim 11, wherein the discovering one or more instances of external resource access includes the steps of:

collecting code and configuration information for a deployed application;

determining entry points in the deployed application;

constructing a call graph rooted at the entry points; 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 the steps of:

classifying the addresses of the one or more constants as positioned in the application code or in the configuration repository; and

resolving the location within configuration file for the locations in the configuration repository.

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 the steps of:

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 one or more 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 the steps of:

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 the steps of:

providing an option to update the one or more 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 non-transitory computer readable medium comprising a computer readable program that executes a tool, wherein the computer readable program when executed by the processor causes the tool to perform the steps of;

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

specifying addresses of the discovered instances of external resource access;

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

updating one or more values of the one or more constants in the application code and the configuration repository;

wherein the application code is updated by replacing at least one of the one or more values of the one or more constants with one or more updated values of the one or more constants; and

wherein the updating includes matching one or more addresses of the external resources with a table mapping the one or more addresses of the one or more constants to one or more updated constant addresses; and

using the one or more updated values of the one or more constants in the application code and the configuration repository in current or future migrations.

22. The system as recited in claim 21, wherein the tool creates 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.