Package org.checkerframework.checker.nullness

Class NullnessChecker

java.lang.Object
javax.annotation.processing.AbstractProcessor
org.checkerframework.javacutil.AbstractTypeProcessor
org.checkerframework.framework.source.SourceChecker
org.checkerframework.common.basetype.BaseTypeChecker
org.checkerframework.checker.initialization.InitializationChecker
org.checkerframework.checker.nullness.NullnessChecker
All Implemented Interfaces:
Processor, OptionConfiguration
@SupportedLintOptions({"noInitForMonotonicNonNull","redundantNullComparison","soundArrayCreationNullness","forbidnonnullarraycomponents","trustArrayLenZero","permitClearProperty"}) @SupportedOptions({"assumeKeyFor","invocationPreservesArgumentNullness"}) @StubFiles({"junit-assertions.astub","log4j.astub"}) public class NullnessChecker extends InitializationChecker
An implementation of the nullness type-system, parameterized by an initialization type-system for safe initialization. It uses freedom-before-commitment, augmented by type frames (which are crucial to obtain acceptable precision), as its initialization type system.
See the Checker Framework Manual:
Nullness Checker

  • Field Details

  • Constructor Details

    • NullnessChecker

      public NullnessChecker()
      Default constructor for NullnessChecker.

  • Method Details

    • getImmediateSubcheckerClasses

      protected Set<Class<? extends SourceChecker>> getImmediateSubcheckerClasses()
      Description copied from class: SourceChecker
      Returns the set of subchecker classes on which this checker depends. ("Depends" means the checkers that are subcheckers of the current checker rather than a subchecker of some other checker.) Returns an empty set if this checker does not depend on any others.

      If this checker should run multiple independent checkers and not contain a type system, then subclass AggregateChecker.

      Subclasses should override this method to specify subcheckers. If they do so, they should call the super implementation of this method and add dependencies to the returned set so that checkers required for reflection resolution are included if reflection resolution is requested.

      If a checker should be added or not based on a command line option, use SourceChecker.getOptionsNoSubcheckers() or SourceChecker.hasOptionNoSubcheckers(String) to avoid recursively calling this method.

      Each subchecker of this checker may also depend on other checkers. If this checker and one of its subcheckers both depend on a third checker, that checker will only be instantiated once.

      Though each checker is run on a whole compilation unit before the next checker is run, error and warning messages are collected and sorted based on the location in the source file before being printed. (See SourceChecker.printOrStoreMessage(Diagnostic.Kind, String, Tree, CompilationUnitTree).)

      WARNING: Circular dependencies are not supported. (In other words, if checker A depends on checker B, checker B cannot depend on checker A.) The Checker Framework does not check for circularity. Make sure no circular dependencies are created when overriding this method.

      This method is protected so it can be overridden, but it should only be called internally by SourceChecker.

      Overrides:
      getImmediateSubcheckerClasses in class SourceChecker
      Returns:
      the subchecker classes on which this checker depends; will be modified by callees

    • getSuppressWarningsPrefixes

      public NavigableSet<String> getSuppressWarningsPrefixes()
      Description copied from class: SourceChecker
      Returns a modifiable set of lower-case strings that are prefixes for SuppressWarnings strings.

      The collection must not be empty and must not contain only SourceChecker.SUPPRESS_ALL_PREFIX.

      Overrides:
      getSuppressWarningsPrefixes in class InitializationChecker
      Returns:
      non-empty modifiable set of lower-case prefixes for SuppressWarnings strings

    • createSourceVisitor

      protected BaseTypeVisitor<?> createSourceVisitor()
      Description copied from class: BaseTypeChecker
      Returns the appropriate visitor that type-checks the compilation unit according to the type system rules.

      This implementation uses the checker naming convention to create the appropriate visitor. If no visitor is found, it returns an instance of BaseTypeVisitor. It reflectively invokes the constructor that accepts this checker and the compilation unit tree (in that order) as arguments.

      Subclasses have to override this method to create the appropriate visitor if they do not follow the checker naming convention.

      Overrides:
      createSourceVisitor in class BaseTypeChecker
      Returns:
      the type-checking visitor