NIFI-16122 Removed redundant type casts and implemented the use of the PMD rule UnnecessaryCast.

[dan-s1]

Summary

NIFI-16122

This PR aims to remove unnecessary casts throughout the code base. For example:

• Casts in places where Java already performs Automatic Type Promotion (or Numeric Promotion).
• Casts to the same type as the variable already was.
• Cast for a method argument where the compiler could already disambiguate the method signature.

Casts that were untouched were:

• Big-Endian byte-to-long conversion where some of the casts are actually needed so the ones not needed were kept for consistency.
• Creating an unsigned 32-bit where the cast was necessary

In these cases the @SuppressWarnings("PMD.UnnecessaryCast") annotation on the method level was added to ignore the use of the cast.

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  • JDK 21
  • JDK 25

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[exceptionfactory]

Thanks @dan-s1, the cleanup and additional PMD rule look good. +1 merging