Interface TypeVisitor<R,P>
-
- Type Parameters:
-
R- the return type of this visitor's methods. UseVoidfor visitors that do not need to return results. -
P- the type of the additional parameter to this visitor's methods. UseVoidfor visitors that do not need an additional parameter.
- All Known Implementing Classes:
- AbstractTypeVisitor6, AbstractTypeVisitor7, AbstractTypeVisitor8, SimpleTypeVisitor6, SimpleTypeVisitor7, SimpleTypeVisitor8, TypeKindVisitor6, TypeKindVisitor7, TypeKindVisitor8
public interface TypeVisitor<R,P>A visitor of types, in the style of the visitor design pattern. Classes implementing this interface are used to operate on a type when the kind of type is unknown at compile time. When a visitor is passed to a type'sacceptmethod, the visitXYZ method most applicable to that type is invoked.Classes implementing this interface may or may not throw a
NullPointerExceptionif the additional parameterpisnull; see documentation of the implementing class for details.WARNING: It is possible that methods will be added to this interface to accommodate new, currently unknown, language structures added to future versions of the Java™ programming language. Therefore, visitor classes directly implementing this interface may be source incompatible with future versions of the platform. To avoid this source incompatibility, visitor implementations are encouraged to instead extend the appropriate abstract visitor class that implements this interface. However, an API should generally use this visitor interface as the type for parameters, return type, etc. rather than one of the abstract classes.
Note that methods to accommodate new language constructs could be added in a source compatible way if they were added as default methods. However, default methods are only available on Java SE 8 and higher releases and the
javax.lang.model.*packages bundled in Java SE 8 are required to also be runnable on Java SE 7. Therefore, default methods cannot be used when extendingjavax.lang.model.*to cover Java SE 8 language features. However, default methods may be used in subsequent revisions of thejavax.lang.model.*packages that are only required to run on Java SE 8 and higher platform versions.- Since:
- 1.6
-
-
Method Summary
All Methods Instance Methods Abstract Methods Modifier and Type Method and Description Rvisit(TypeMirror t)A convenience method equivalent tov.visit(t, null).Rvisit(TypeMirror t, P p)Visits a type.RvisitArray(ArrayType t, P p)Visits an array type.RvisitDeclared(DeclaredType t, P p)Visits a declared type.RvisitError(ErrorType t, P p)Visits an error type.RvisitExecutable(ExecutableType t, P p)Visits an executable type.RvisitIntersection(IntersectionType t, P p)Visits an intersection type.RvisitNoType(NoType t, P p)Visits aNoTypeinstance.RvisitNull(NullType t, P p)Visits the null type.RvisitPrimitive(PrimitiveType t, P p)Visits a primitive type.RvisitTypeVariable(TypeVariable t, P p)Visits a type variable.RvisitUnion(UnionType t, P p)Visits a union type.RvisitUnknown(TypeMirror t, P p)Visits an unknown kind of type.RvisitWildcard(WildcardType t, P p)Visits a wildcard type.
-
-
-
Method Detail
visit
R visit(TypeMirror t, P p)
Visits a type.- Parameters:
-
t- the type to visit -
p- a visitor-specified parameter - Returns:
- a visitor-specified result
visit
R visit(TypeMirror t)
A convenience method equivalent tov.visit(t, null).- Parameters:
-
t- the element to visit - Returns:
- a visitor-specified result
visitPrimitive
R visitPrimitive(PrimitiveType t, P p)
Visits a primitive type.- Parameters:
-
t- the type to visit -
p- a visitor-specified parameter - Returns:
- a visitor-specified result
visitNull
R visitNull(NullType t, P p)
Visits the null type.- Parameters:
-
t- the type to visit -
p- a visitor-specified parameter - Returns:
- a visitor-specified result
visitArray
R visitArray(ArrayType t, P p)
Visits an array type.- Parameters:
-
t- the type to visit -
p- a visitor-specified parameter - Returns:
- a visitor-specified result
visitDeclared
R visitDeclared(DeclaredType t, P p)
Visits a declared type.- Parameters:
-
t- the type to visit -
p- a visitor-specified parameter - Returns:
- a visitor-specified result
visitError
R visitError(ErrorType t, P p)
Visits an error type.- Parameters:
-
t- the type to visit -
p- a visitor-specified parameter - Returns:
- a visitor-specified result
visitTypeVariable
R visitTypeVariable(TypeVariable t, P p)
Visits a type variable.- Parameters:
-
t- the type to visit -
p- a visitor-specified parameter - Returns:
- a visitor-specified result
visitWildcard
R visitWildcard(WildcardType t, P p)
Visits a wildcard type.- Parameters:
-
t- the type to visit -
p- a visitor-specified parameter - Returns:
- a visitor-specified result
visitExecutable
R visitExecutable(ExecutableType t, P p)
Visits an executable type.- Parameters:
-
t- the type to visit -
p- a visitor-specified parameter - Returns:
- a visitor-specified result
visitNoType
R visitNoType(NoType t, P p)
Visits aNoTypeinstance.- Parameters:
-
t- the type to visit -
p- a visitor-specified parameter - Returns:
- a visitor-specified result
visitUnknown
R visitUnknown(TypeMirror t, P p)
Visits an unknown kind of type. This can occur if the language evolves and new kinds of types are added to theTypeMirrorhierarchy.- Parameters:
-
t- the type to visit -
p- a visitor-specified parameter - Returns:
- a visitor-specified result
- Throws:
-
UnknownTypeException- a visitor implementation may optionally throw this exception
visitUnion
R visitUnion(UnionType t, P p)
Visits a union type.- Parameters:
-
t- the type to visit -
p- a visitor-specified parameter - Returns:
- a visitor-specified result
- Since:
- 1.7
visitIntersection
R visitIntersection(IntersectionType t, P p)
Visits an intersection type.- Parameters:
-
t- the type to visit -
p- a visitor-specified parameter - Returns:
- a visitor-specified result
- Since:
- 1.8
-
Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2022, Oracle and/or its affiliates. All rights reserved. Use is subject to license terms. Also see the documentation redistribution policy.
