Class BaseTypeChecker

All Implemented Interfaces:
Processor, OptionConfiguration
Direct Known Subclasses:
AccumulationChecker, AliasingChecker, ClassValChecker, FenumChecker, FormatterChecker, GuiEffectChecker, I18nFormatterChecker, I18nSubchecker, InitializationChecker, InterningChecker, KeyForSubchecker, LessThanChecker, LockChecker, LowerBoundChecker, MethodValChecker, MustCallChecker, NonEmptyChecker, OptionalChecker, PropertyKeyChecker, PurityChecker, RegexChecker, ReportChecker, ReturnsReceiverChecker, SameLenChecker, SearchIndexChecker, SignatureChecker, SignednessChecker, SubstringIndexChecker, SubtypingChecker, TaintingChecker, TypeOutputtingChecker, UnitsChecker, UpperBoundChecker, ValueChecker

public abstract class BaseTypeChecker extends SourceChecker
An abstract SourceChecker that provides a simple SourceVisitor implementation that type-checks assignments, pseudo-assignments such as parameter passing and method invocation, and method overriding.

Most type-checker annotation processors should extend this class, instead of SourceChecker. Checkers that require annotated types but not subtype checking (e.g. for testing purposes) should extend SourceChecker. Non-type checkers (e.g. checkers to enforce coding styles) can extend SourceChecker or AbstractTypeProcessor; the Checker Framework is not specifically designed to support such checkers.

It is a convention that, for a type system Foo, the checker, the visitor, and the annotated type factory are named as FooChecker, FooVisitor, and FooAnnotatedTypeFactory. Some factory methods use this convention to construct the appropriate classes reflectively.

BaseTypeChecker encapsulates a group for factories for various representations/classes related the type system, mainly:

  • QualifierHierarchy: to represent the supported qualifiers in addition to their hierarchy, mainly, subtyping rules
  • TypeHierarchy: to check subtyping rules between annotated types rather than qualifiers
  • AnnotatedTypeFactory: to construct qualified types enriched with default qualifiers according to the type system rules
  • BaseTypeVisitor: to visit the compiled Java files and check for violations of the type system rules

Subclasses must specify the set of type qualifiers they support. See AnnotatedTypeFactory.createSupportedTypeQualifiers().

If the specified type qualifiers are meta-annotated with SubtypeOf, this implementation will automatically construct the type qualifier hierarchy. Otherwise, or if this behavior must be overridden, the subclass may override the AnnotatedTypeFactory.createQualifierHierarchy() method.

See the Checker Framework Manual:
The checker class
  • Constructor Details

    • BaseTypeChecker

      public BaseTypeChecker()
  • Method Details

    • initChecker

      public void initChecker()
      Description copied from class: SourceChecker
      Initialize the checker.
      Overrides:
      initChecker in class SourceChecker
      See Also:
    • setRoot

      protected void setRoot(CompilationUnitTree newRoot)
      Description copied from class: SourceChecker
      Invoked when the current compilation unit root changes.
      Overrides:
      setRoot in class SourceChecker
      Parameters:
      newRoot - the new compilation unit root
    • getImmediateSubcheckerClasses

      protected Set<Class<? extends BaseTypeChecker>> getImmediateSubcheckerClasses()
      Returns the set of subchecker classes on which this checker depends. Returns an empty set if this checker does not depend on any others.

      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.

      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 printOrStoreMessage(Diagnostic.Kind, String, Tree, CompilationUnitTree).)

      WARNING: Circular dependencies are not supported nor do checkers verify that their dependencies are not circular. Make sure no circular dependencies are created when overriding this method. (In other words, if checker A depends on checker B, checker B cannot depend on checker A.)

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

      The BaseTypeChecker will not modify the list returned by this method, but other clients do modify the list.

      Returns:
      the subchecker classes on which this checker depends; will be modified by callees
    • shouldResolveReflection

      public boolean shouldResolveReflection()
      Returns whether or not reflection should be resolved.
      Returns:
      true if reflection should be resolved
    • createSourceVisitor

      protected BaseTypeVisitor<?> createSourceVisitor()
      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.

      Specified by:
      createSourceVisitor in class SourceChecker
      Returns:
      the type-checking visitor
    • createSourceVisitorPublic

      public BaseTypeVisitor<?> createSourceVisitorPublic()
      A public variant of createSourceVisitor(). Only use this if you know what you are doing.
      Returns:
      the type-checking visitor
    • getRelatedClassName

      public static @ClassGetName String getRelatedClassName(Class<?> checkerClass, String replacement)
      Returns the name of a class related to a given one, by replacing "Checker" or "Subchecker" by replacement.
      Parameters:
      checkerClass - the checker class
      replacement - the string to replace "Checker" or "Subchecker" by
      Returns:
      the name of the related class
    • getSupportedLintOptions

      public Set<String> getSupportedLintOptions()
      Specify supported lint options for all type-checkers.
      Overrides:
      getSupportedLintOptions in class SourceChecker
      Returns:
      an unmodifiable Set of the lint options recognized by this checker
    • invokeConstructorFor

      public static <T> @Nullable T invokeConstructorFor(@ClassGetName String name, Class<?>[] paramTypes, Object[] args)
      Invokes the constructor belonging to the class named by name having the given parameter types on the given arguments. Returns null if the class cannot be found. Otherwise, throws an exception if there is trouble with the constructor invocation.
      Type Parameters:
      T - the type to which the constructor belongs
      Parameters:
      name - the name of the class to which the constructor belongs
      paramTypes - the types of the constructor's parameters
      args - the arguments on which to invoke the constructor
      Returns:
      the result of the constructor invocation on args, or null if the class does not exist
    • getVisitor

      public BaseTypeVisitor<?> getVisitor()
      Description copied from class: SourceChecker
      Returns the SourceVisitor associated with this.
      Overrides:
      getVisitor in class SourceChecker
      Returns:
      the SourceVisitor associated with this
    • getTypeFactory

      public GenericAnnotatedTypeFactory<?,?,?,?> getTypeFactory()
      Return the type factory associated with this checker.
      Returns:
      the type factory associated with this checker
    • getAnnotationProvider

      public AnnotationProvider getAnnotationProvider()
      Description copied from class: SourceChecker
      Returns the AnnotationProvider (the type factory) associated with this.
      Overrides:
      getAnnotationProvider in class SourceChecker
      Returns:
      the AnnotationProvider (the type factory) associated with this
    • getSubchecker

      public <T extends BaseTypeChecker> @Nullable T getSubchecker(Class<T> checkerClass)
      Returns the requested subchecker. A checker of a given class can only be run once, so this returns the only such checker, or null if none was found. The caller must know the exact checker class to request.
      Type Parameters:
      T - the class of the subchecker to return
      Parameters:
      checkerClass - the class of the subchecker to return
      Returns:
      the requested subchecker or null if not found
    • getTypeFactoryOfSubcheckerOrNull

      public <T extends GenericAnnotatedTypeFactory<?, ?, ?, ?>> @Nullable T getTypeFactoryOfSubcheckerOrNull(Class<? extends BaseTypeChecker> subCheckerClass)
      Returns the type factory used by a subchecker. Returns null if no matching subchecker was found or if the type factory is null. The caller must know the exact checker class to request.

      Because the visitor state is copied, call this method each time a subfactory is needed rather than store the returned subfactory in a field.

      Type Parameters:
      T - the type of subCheckerClass's AnnotatedTypeFactory
      Parameters:
      subCheckerClass - the class of the subchecker
      Returns:
      the type factory of the requested subchecker or null if not found
    • getSubcheckers

      public List<BaseTypeChecker> getSubcheckers()
      Get the list of all subcheckers (if any). via the instantiateSubcheckers method. This list is only non-empty for the one checker that runs all other subcheckers. These are recursively instantiated via instantiateSubcheckers the first time the method is called if subcheckers is null. Assumes all checkers run on the same thread.
      Returns:
      the list of all subcheckers (if any)
    • getTreePathCacher

      public TreePathCacher getTreePathCacher()
      Get the shared TreePathCacher instance.
    • typeProcess

      public void typeProcess(TypeElement element, TreePath tree)
      Description copied from class: SourceChecker
      Type-check the code using this checker's visitor.
      Overrides:
      typeProcess in class SourceChecker
      Parameters:
      element - element of the analyzed class
      tree - the tree path to the element, with the leaf being a ClassTree
      See Also:
    • getSuppressWarningsPrefixesOfSubcheckers

      public Collection<String> getSuppressWarningsPrefixesOfSubcheckers()
      Like SourceChecker.getSuppressWarningsPrefixes(), but includes all prefixes supported by this checker or any of its subcheckers. Does not guarantee that the result is in any particular order. The result is immutable.
      Returns:
      the suppress warnings prefixes supported by this checker or any of its subcheckers
    • getUltimateParentChecker

      public BaseTypeChecker getUltimateParentChecker()
      Finds the ultimate parent checker of this checker. The ultimate parent checker is the checker that the user actually requested, i.e. the one with no parent. The ultimate parent might be this checker itself.
      Returns:
      the first checker in the parent checker chain with no parent checker of its own, i.e., the ultimate parent checker
    • warnUnneededSuppressions

      protected void warnUnneededSuppressions()
      Issues a warning about any @SuppressWarnings that didn't suppress a warning, but starts with this checker name or "allcheckers".

      This implementation collects needed warning suppressions for all subcheckers.

      Overrides:
      warnUnneededSuppressions in class SourceChecker
    • printOrStoreMessage

      protected void printOrStoreMessage(Diagnostic.Kind kind, String message, Tree source, CompilationUnitTree root)
      If this is a compound checker or a subchecker of a compound checker, then the message is stored until all messages from all checkers for the compilation unit are issued.

      Otherwise, it prints the message.

      Overrides:
      printOrStoreMessage in class SourceChecker
      Parameters:
      kind - the kind of message to print
      message - the message text
      source - the source code position of the diagnostic message
      root - the compilation unit
    • typeProcessingOver

      public void typeProcessingOver()
      Description copied from class: AbstractTypeProcessor
      A method to be called once all the classes are processed.

      Subclasses may override this method to do any aggregate analysis (e.g. generate report, persistence) or resource deallocation.

      Method AbstractTypeProcessor.getCompilerLog() can be used to access the number of compiler errors.

      Overrides:
      typeProcessingOver in class AbstractTypeProcessor
    • getSupportedOptions

      public Set<String> getSupportedOptions()
      Description copied from interface: OptionConfiguration
      Map the Checker Framework version of SupportedOptions to the standard annotation provided version SupportedOptions.
      Specified by:
      getSupportedOptions in interface OptionConfiguration
      Specified by:
      getSupportedOptions in interface Processor
      Overrides:
      getSupportedOptions in class SourceChecker
      Returns:
      the supported options
    • getOptions

      public Map<String,String> getOptions()
      Description copied from interface: OptionConfiguration
      Return all active options for this checker.
      Specified by:
      getOptions in interface OptionConfiguration
      Overrides:
      getOptions in class SourceChecker
      Returns:
      all active options for this checker
    • getOptionsNoSubcheckers

      public Map<String,String> getOptionsNoSubcheckers()
      Like getOptions(), but only includes options provided to this checker. Does not include those passed to subcheckers.
      Returns:
      the active options for this checker, not including those passed to subcheckers
    • hasOptionNoSubcheckers

      public final boolean hasOptionNoSubcheckers(String name)
      Like SourceChecker.hasOption(java.lang.String), but checks whether the given option is provided to this checker. Does not consider those passed to subcheckers.
      Parameters:
      name - the name of the option to check
      Returns:
      true if the option name was provided to this checker, false otherwise
    • getExtraStubFiles

      public List<String> getExtraStubFiles()
      Return a list of additional stub files to be treated as if they had been written in a @StubFiles annotation.
      Returns:
      stub files to be treated as if they had been written in a @StubFiles annotation
    • processErrorMessageArg

      protected Object processErrorMessageArg(Object arg)
      Description copied from class: SourceChecker
      Process an argument to an error message before it is passed to String.format.

      This implementation expands the argument if it is exactly a message key.

      By contrast, SourceChecker.fullMessageOf(java.lang.String, java.lang.String) processes the message key itself but not the arguments, and tries suffixes.

      Overrides:
      processErrorMessageArg in class SourceChecker
      Parameters:
      arg - the argument
      Returns:
      the result after processing
    • shouldAddShutdownHook

      protected boolean shouldAddShutdownHook()
      Description copied from class: SourceChecker
      Return true to indicate that method SourceChecker.shutdownHook() should be added as a shutdownHook of the JVM.
      Overrides:
      shouldAddShutdownHook in class SourceChecker
      Returns:
      true to add SourceChecker.shutdownHook() as a shutdown hook of the JVM
    • shutdownHook

      protected void shutdownHook()
      Description copied from class: SourceChecker
      Method that gets called exactly once at shutdown time of the JVM. Checkers can override this method to customize the behavior.

      If you override this, you must also override SourceChecker.shouldAddShutdownHook() to return true.

      Overrides:
      shutdownHook in class SourceChecker