Method, apparatus, and program for using a Java archive to encode a file system delta

• US 20030225795A1
• Filed: 05/29/2002
• Published: 12/04/2003
• Est. Priority Date: 05/29/2002
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Abdallah, Nebeel W., Bitonti, Thomas F., Jerkewitz, Hans P.
• Granted Patent: US 6,999,976 B2
• Time in Patent Office: Days
• US Class Current: 707/200
• CPC Class Codes: G06F 16/10 File systems; File servers
• CPC Class Codes: G06F 8/658 Incremental updates; Differential updates
• CPC Class Codes: Y10S 707/99953 Recoverability

Abstract

A mechanism is provided for extending a Java archive file to include additional information that describes the contents of the archive as update information. A program is provided for determining differences between an initial file system tree and a final file system tree and encoding those differences into entries in a Java archive file. An extractor class is included in the Java archive file and named as the main class. The Java archive file may be transported to a site that needs a file system update. The Java archive file may be executed in a Java runtime environment to update a target file system. The extractor class is executed to decode and effectuate the difference entries in the archive file.

Claims

1. A method for providing an update to a file system, comprising:

determining at least one difference between an initial file system tree and a final file system tree;

creating a delta Java archive file; and

placing at least one difference entry, describing a difference between the initial file system tree and the final file system tree, into the delta Java archive file.

2. The method of claim 1, further comprising:

placing an extractor class into the delta Java archive.

3. The method of claim 2, further comprising:

placing a main class specification into the delta Java archive file naming the extractor class as the main class.

4. The method of claim 1, wherein the at least one difference entry comprises at least one of a directory remove entry, a directory create entry, a directory attribute update entry, a file remove entry, a file create entry, a file attribute update entry, a file content update entry, a file content update entry, a file attribute update entry, a file create/directory remove entry, and a file remove/directory create entry.

5. The method of claim 1, further comprising:

transporting the delta Java archive file to a destination computer.

6. The method of claim 5, further comprising:

identifying a target file system tree at the destination computer;

receiving, at the destination computer, a delta Java archive that includes at least one difference entry and an extractor class; and

executing the extractor class, wherein the extractor class applies difference information in the at least one difference entry to the target file system tree to form a final file system tree.

7. The method of claim 6, wherein the extractor class applies the difference information by performing an update operation comprising at least one of removing a file, removing a directory, creating a directory, updating directory attributes, placing file contents, and updating file attributes.

8. A method for updating a file system, comprising:

identifying a target file system tree;

receiving a delta Java archive that includes at least one difference entry and an extractor class; and

executing the extractor class, wherein the extractor class applies difference information in the at least one difference entry to the target file system tree to form a final file system tree.

9. The method of claim 8, wherein the extractor class applies the difference information by performing an update operation comprising at least one of removing a file, removing a directory, creating a directory, updating directory attributes, placing file contents, and updating file attributes.

10. The method of claim 8, wherein the delta Java archive file includes a main class specification the extractor class as the main class.

11. The method of claim 10, wherein the step of executing the extractor class is performed by executing the Java archive file relative to the target file system tree.

12. An apparatus for providing an update to a file system, comprising:

determination means for determining at least one difference between an initial file system tree and a final file system tree;

creation means for creating a delta Java archive file; and

entry means for placing at least one difference entry, describing a difference between the initial file system tree and the final file system tree, into the delta Java archive file.

13. The apparatus of claim 12, further comprising:

means for placing an extractor class into the delta Java archive.

14. The apparatus of claim 13, further comprising:

means for placing a main class specification into the delta Java archive file naming the extractor class as the main class.

15. The apparatus of claim 12, wherein the at least one difference entry comprises at least one of a directory remove entry, a directory create entry, a directory attribute update entry, a file remove entry, a file create entry, a file attribute update entry, a file content update entry, a file content update entry, a file attribute update entry, a file create/directory remove entry, and a file remove/directory create entry.

16. The apparatus of claim 12, further comprising:

transportation means for transporting the delta Java archive file to a destination computer.

17. The apparatus of claim 16, further comprising:

identification means for identifying a target file system tree at the destination computer;

receipt means for receiving, at the destination computer, a delta Java archive that includes at least one difference entry and an extractor class; and

execution means for executing the extractor class, wherein the extractor class applies difference information in the at least one difference entry to the target file system tree to form a final file system tree.

18. The apparatus of claim 17, wherein the extractor class applies the difference information by performing an update operation comprising at least one of removing a file, removing a directory, creating a directory, updating directory attributes, placing file contents, and updating file attributes.

19. An apparatus for updating a file system, comprising:

identification means for identifying a target file system tree;

receipt means for receiving a delta Java archive that includes at least one difference entry and an extractor class; and

execution means for executing the extractor class, wherein the extractor class applies difference information in the at least one difference entry to the target file system tree to form a final file system tree.

20. The apparatus of claim 19, wherein the extractor class applies the difference information by performing an update operation comprising at least one of removing a file, removing a directory, creating a directory, updating directory attributes, placing file contents, and updating file attributes.

21. The apparatus of claim 19, wherein the delta Java archive file includes a main class specification the extractor class as the main class.

22. The apparatus of claim 21, wherein the execution means executes the extractor class by executing the Java archive file relative to the target file system tree.

23. A data structure for providing an update to a file system, comprising:

a delta Java archive including;

at least one difference entry describing a difference between an initial file system tree and a final file system tree; and

an extractor class wherein the extractor class is configured to apply difference information in the at least one difference entry to a target file system tree to form the final file system tree.

24. A computer program product, in a computer readable medium, for providing an update to a file system, comprising:

instructions for determining at least one difference between an initial file system tree and a final file system tree;

instructions for creating a delta Java archive file; and

instructions for placing at least one difference entry, describing a difference between the initial file system tree and the final file system tree, into the delta Java archive file.

25. A computer program product, in a computer readable medium, for updating a file system, comprising:

instructions for identifying a target file system tree;

instructions for receiving a delta Java archive that includes at least one difference entry and an extractor class; and

instructions for executing the extractor class, wherein the extractor class applies difference information in the at least one difference entry to the target file system tree to form a final file system tree.