Package groovy.transform.stc

Class PickAnyArgumentHint

java.lang.Object
groovy.transform.stc.ClosureSignatureHint
groovy.transform.stc.SingleSignatureClosureHint
groovy.transform.stc.PickAnyArgumentHint
Direct Known Subclasses:
FirstParam, FirstParam.FirstGenericType, FirstParam.SecondGenericType, FirstParam.ThirdGenericType, SecondParam, SecondParam.FirstGenericType, SecondParam.SecondGenericType, SecondParam.ThirdGenericType, ThirdParam, ThirdParam.FirstGenericType, ThirdParam.SecondGenericType, ThirdParam.ThirdGenericType
public class PickAnyArgumentHint extends SingleSignatureClosureHint

Base class for hints which use the type of a parameter of the annotated method as the signature. This can optionally use a generic type of the selected parameter as the hint. For example, imagine the following method:

void foo(A firstArg, B secondArg, Closure c) {...}

If the c closure should be { B it -> ...}, then we can see that the parameter type should be picked from the second parameter of the foo method, which is what PickAnyArgumentHint lets you do.

Alternatively, the method may look like this:

void <T> foo(A<T> firstArg, B secondArg, Closure c) {...}

in which case if you want to express the fact that c should accept a <T> then you can use the genericTypeIndex value.

This class is extended by several hint providers that make it easier to use as annotation values.

Since:
2.3.0

  • Constructor Details

    • PickAnyArgumentHint

      public PickAnyArgumentHint()
      Creates an argument picker which extracts the type of the first parameter.

    • PickAnyArgumentHint

      public PickAnyArgumentHint(int parameterIndex, int genericTypeIndex)
      Creates a picker which will extract the parameterIndex-th parameter type, or its genericTypeIndex-th generic type genericTypeIndex is >=0.
      Parameters:
      parameterIndex - the index of the parameter from which to extract the type
      genericTypeIndex - if >=0, then returns the corresponding generic type instead of the parameter type.

  • Method Details

    • getParameterTypes

      public ClassNode[] getParameterTypes(MethodNode node, String[] options, SourceUnit sourceUnit, CompilationUnit unit, ASTNode usage)
      Returns the single parameter signature accepted by the hinted closure.
      Specified by:
      getParameterTypes in class SingleSignatureClosureHint
      Parameters:
      node - the annotated method node
      options - the hint options
      sourceUnit - the current source unit
      unit - the current compilation unit
      usage - the closure expression or related AST node
      Returns:
      the inferred parameter types