Remove code for JDK 5 and 6

[nyg]

As this fork of jmxterm is compiled with JDK 17, it make no sense to keep code that is specific to the (very) old JDK 5 and 6.

Let me know if you want more details on the changes.

[Copilot]

Pull Request Overview

This PR removes legacy code for JDK 5 and 6 compatibility from the jmxterm fork, since it's now compiled with JDK 17. The changes modernize the codebase by eliminating obsolete version-specific implementations and simplifying the process manager factory.

• Removes all JDK 5 and 6 specific classes and their reflection-based implementations
• Eliminates dynamic JDK version detection and weak casting utilities
• Simplifies the process manager factory to only support JDK 9+ functionality

Reviewed Changes

Copilot reviewed 29 out of 29 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
WeakCastUtils.java	Removes reflection utility class used for legacy JDK compatibility
UnsupportedJavaProcessManager.java	Removes fallback process manager implementation
JConsoleClassLoaderFactory.java	Removes class loader factory for tools.jar/jconsole.jar handling
jdk5/ and jdk6/ packages	Removes entire packages with JDK-specific implementations
jdk9/ package	Modernizes to use direct JDK API instead of reflection
JPMFactory.java	Simplifies to only create JDK 9+ process managers
Test files	Updates test classes to use modernized implementations

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[Copilot]

Pull Request Overview

Copilot reviewed 30 out of 30 changed files in this pull request and generated 3 comments.