Fix #341: Add model classes for java.util.logging

[HritikRaj2]

Problem

JPF crashes when code calls Logger.getLogger() because the real JDK implementation relies on native methods (e.g., jdk.internal.misc.VM.initializeFromArchive), unsupported Thread constructors, and complex security/filesystem APIs that are not supported in the Model Java Interface (MJI).

Solution

Implemented a set of model classes for the java.util.logging package. These models provide a simplified, pure-Java implementation compatible with JPF that supports basic logging operations, handler management, and stream output without relying on native JDK internals.

Changes

• src/classes/modules/java.logging/java/util/logging/Logger.java: Updated to support adding/removing handlers and publishing log records.
• src/classes/modules/java.logging/java/util/logging/LogManager.java: Minimal implementation to manage logger instances.
• src/classes/modules/java.logging/java/util/logging/Level.java: Model class defining standard log levels.
• src/classes/modules/java.logging/java/util/logging/Handler.java: Abstract base class for log handlers.
• src/classes/modules/java.logging/java/util/logging/StreamHandler.java: Implements log publishing to an output stream (throws IOException correctly on flush).
• src/classes/modules/java.logging/java/util/logging/LogRecord.java: Encapsulates log data.
• src/classes/modules/java.logging/java/util/logging/Formatter.java: Abstract base for log formatting.
• src/tests/gov/nasa/jpf/test/java/util/LoggerTest.java: New test case verifying logger caching and output capturing via ByteArrayOutputStream (assertions only, no console printing).

Testing

All existing tests pass + new test confirms Logger.getLogger() works without crashes.

[cyrille-artho]

Looks good!
Please add the copyright header (the first five lines of comments that is present in all files and also about half of the new files you have created) to the remaining files.

[HritikRaj2]

@cyrille-artho
Thank you for the review!
I have added the standard copyright header to all the new files (Handler, StreamHandler, LogRecord, Formatter, LogManager) as requested.

[HritikRaj2]

@cyrille-artho
When ever you get time please have a look on the changes
and also check #580 so i can do changes in it if required.