[RFC] Java Cleanup - Errors & Warnings

[currantw]

Is your feature request related to a problem?

The code inspections tool in IntelliJ IDEA generates thousands of warnings and errors when compiling this project. These range from trivial code quality warnings (e.g. unused imports or unnecessary toString calls) to more serious errors (e.g. for deprecated APIs). While some of these will be difficult to fix, many are trivial to resolve: we should take advantage of these by addressing them gradually in order to improve quality and performance.

What solution would you like?

We should gradually address these errors and warnings, starting with those that are either trivial to fix (i.e. they can be resolved with a batch "Quick Fix") or higher severity (i.e. they could cause bugs or other issues). The lists below represent a rough grouping of some of the errors and warnings that I think it would be easiest and/or most valuable to address.

Higher severity or possible bugs:

• Deprecated API usage (983 warnings)
• Usage of API marked for removal (66 errors)
• Optional.get() is called without isPresent() check (11 warnings)
• String comparison with == instead of equals() (2 warnings)
• Wrong package statement (24 errors)
• JUnit 5 obselete assertions (52 warnings)

Trivial to fix:

• Field may be final (279 warnings) - Mark Constant Fields as final #3191
• size == 0 can be replaced with isEmpty (61 warnings)
• Unnecessary call to toString() (102 warnings)
• Lombok @Getter may be used (203 warnings)
• Lombok @Setter may be used (47 warnings)
• Redundant String operation (21 warnings)
• Redundant type cast (71 warnings)
• Stream API call chain can be simplified (27 warnings)
• Unnecessarily escaped character (22 warnings)
• Misordered assertEquals() arguments (131 warnings)
• Simplifiable assertion (164 warnings)
• Unused assignment (25 warnings)
• Wrapper type may be primitive (35 warnings)
• String.equals() can be replaced with String.isEmpty() (5 warnings)
• Redundant call to String.format() (8 warnings)
• Redundant local variable (35 warnings)
• Redundant throws clause (190 warnings)
• Declaration can have final modifier (382 warnings)
• Statement can be replaced with enhanced switch (59 warnings)
• Text block can be used (193 warnings)
• Class can be record class (58 warnings)
• Pattern variable can be used (107 warnings)
• SequencedCollection method (e.g. getFirst()) can be used (348 warnings)
• for loop can be replaced with enhanced for loop (11 warnings)
• Raw use of parametrized class (207 warnings)
• Explicit type can be replaced with <> (98 warnings)
• Anonymous type can be replaced with lambda (4 warnings)
• Lambda can be replaced with method reference (37 warnings)
• Statement lambda can be replaced with expression lambda (45 warnings)
• if can be replaced with switch (21 warnings)

What alternatives have you considered?

We could ignore these errors completely, or ignore some of them. We could choose to address different errors and/or prioritize them differently.

Do you have any additional context?

None.

[YANG-DB]

@currantw thanks - looks great