Reports classes that may be made final because they cannot be extended from outside their compilation unit anyway. This is because all their constructors are private, so a subclass could not call the super constructor. ClassWithOnlyPrivateConstructorsShouldBeFinal (Priority: 1, Ruleset: Design) https://docs.pmd-code.org/pmd-doc-7.6.0/pmd_rules_java_design.html#classwithonlyprivateconstructorsshouldbefinal

Non-private static fields should be made constants (or immutable references) by declaring them final. Non-private non-final static fields break encapsulation and can lead to hard to find bugs, since these fields can be modified from anywhere within the program. Callers can trivially access and modify non-private non-final static fields. Neither accesses nor modifications can be guarded against, and newly set values cannot be validated. If you are using this rule, then you don't need this rule {% rule java/errorprone/AssignmentToNonFinalStatic %}. MutableStaticState (Priority: 3, Ruleset: Design) https://docs.pmd-code.org/pmd-doc-7.6.0/pmd_rules_java_design.html#mutablestaticstate

Non-private static fields should be made constants (or immutable references) by declaring them final. Non-private non-final static fields break encapsulation and can lead to hard to find bugs, since these fields can be modified from anywhere within the program. Callers can trivially access and modify non-private non-final static fields. Neither accesses nor modifications can be guarded against, and newly set values cannot be validated. If you are using this rule, then you don't need this rule {% rule java/errorprone/AssignmentToNonFinalStatic %}. MutableStaticState (Priority: 3, Ruleset: Design) https://docs.pmd-code.org/pmd-doc-7.6.0/pmd_rules_java_design.html#mutablestaticstate

Non-private static fields should be made constants (or immutable references) by declaring them final. Non-private non-final static fields break encapsulation and can lead to hard to find bugs, since these fields can be modified from anywhere within the program. Callers can trivially access and modify non-private non-final static fields. Neither accesses nor modifications can be guarded against, and newly set values cannot be validated. If you are using this rule, then you don't need this rule {% rule java/errorprone/AssignmentToNonFinalStatic %}. MutableStaticState (Priority: 3, Ruleset: Design) https://docs.pmd-code.org/pmd-doc-7.6.0/pmd_rules_java_design.html#mutablestaticstate

Non-private static fields should be made constants (or immutable references) by declaring them final. Non-private non-final static fields break encapsulation and can lead to hard to find bugs, since these fields can be modified from anywhere within the program. Callers can trivially access and modify non-private non-final static fields. Neither accesses nor modifications can be guarded against, and newly set values cannot be validated. If you are using this rule, then you don't need this rule {% rule java/errorprone/AssignmentToNonFinalStatic %}. MutableStaticState (Priority: 3, Ruleset: Design) https://docs.pmd-code.org/pmd-doc-7.6.0/pmd_rules_java_design.html#mutablestaticstate

Non-private static fields should be made constants (or immutable references) by declaring them final. Non-private non-final static fields break encapsulation and can lead to hard to find bugs, since these fields can be modified from anywhere within the program. Callers can trivially access and modify non-private non-final static fields. Neither accesses nor modifications can be guarded against, and newly set values cannot be validated. If you are using this rule, then you don't need this rule {% rule java/errorprone/AssignmentToNonFinalStatic %}. MutableStaticState (Priority: 3, Ruleset: Design) https://docs.pmd-code.org/pmd-doc-7.6.0/pmd_rules_java_design.html#mutablestaticstate

Non-private static fields should be made constants (or immutable references) by declaring them final. Non-private non-final static fields break encapsulation and can lead to hard to find bugs, since these fields can be modified from anywhere within the program. Callers can trivially access and modify non-private non-final static fields. Neither accesses nor modifications can be guarded against, and newly set values cannot be validated. If you are using this rule, then you don't need this rule {% rule java/errorprone/AssignmentToNonFinalStatic %}. MutableStaticState (Priority: 3, Ruleset: Design) https://docs.pmd-code.org/pmd-doc-7.6.0/pmd_rules_java_design.html#mutablestaticstate

Non-private static fields should be made constants (or immutable references) by declaring them final. Non-private non-final static fields break encapsulation and can lead to hard to find bugs, since these fields can be modified from anywhere within the program. Callers can trivially access and modify non-private non-final static fields. Neither accesses nor modifications can be guarded against, and newly set values cannot be validated. If you are using this rule, then you don't need this rule {% rule java/errorprone/AssignmentToNonFinalStatic %}. MutableStaticState (Priority: 3, Ruleset: Design) https://docs.pmd-code.org/pmd-doc-7.6.0/pmd_rules_java_design.html#mutablestaticstate

Non-private static fields should be made constants (or immutable references) by declaring them final. Non-private non-final static fields break encapsulation and can lead to hard to find bugs, since these fields can be modified from anywhere within the program. Callers can trivially access and modify non-private non-final static fields. Neither accesses nor modifications can be guarded against, and newly set values cannot be validated. If you are using this rule, then you don't need this rule {% rule java/errorprone/AssignmentToNonFinalStatic %}. MutableStaticState (Priority: 3, Ruleset: Design) https://docs.pmd-code.org/pmd-doc-7.6.0/pmd_rules_java_design.html#mutablestaticstate

Detects when a private field is declared and/or assigned a value, but not used. Since PMD 6.50.0 private fields are ignored, if the fields are annotated with any annotation or the enclosing class has any annotation. Annotations often enable a framework (such as dependency injection, mocking or e.g. Lombok) which use the fields by reflection or other means. This usage can't be detected by static code analysis. Previously these frameworks where explicitly allowed by listing their annotations in the property "ignoredAnnotations", but that turned out to be prone of false positive for any not explicitly considered framework. UnusedPrivateField (Priority: 3, Ruleset: Best Practices) https://docs.pmd-code.org/pmd-doc-7.6.0/pmd_rules_java_bestpractices.html#unusedprivatefield