# Class AbstractTypeVisitor6<R,P>

java.lang.Object
javax.lang.model.util.AbstractTypeVisitor6<R,P>

Type Parameters:
  `R` - the return type of this visitor's methods. Use `Void` for visitors that do not need to return results.
  `P` - the type of the additional parameter to this visitor's methods. Use `Void` for visitors that do not need an additional parameter.

All Implemented Interfaces:
  `TypeVisitor<R,P>`

Direct Known Subclasses:
  `AbstractTypeVisitor7, SimpleTypeVisitor6`

@SupportedSourceVersion(RELEASE_6) public abstract class AbstractTypeVisitor6<R,P> extends Object implements TypeVisitor<R,P>
A skeletal visitor of types with default behavior appropriate for the `RELEASE_6` source version.

API Note:

  WARNING: The `TypeVisitor` interface implemented by this class may have methods added to it in the future to accommodate new, currently unknown, language structures added to future versions of the Java programming language. Therefore, methods whose names begin with `"visit"` may be added to this class in the future; to avoid incompatibilities, classes and subclasses which extend this class should not declare any instance methods with names beginning with `"visit"`.

  When such a new visit method is added, the default implementation in this class will be to directly or indirectly call the `visitUnknown` method. A new abstract type visitor class will also be introduced to correspond to the new language level; this visitor will have different default behavior for the visit method in question. When a new visitor is introduced, portions of this visitor class may be deprecated, including its constructors.

Since:
  1.6
See Also:
  - `AbstractTypeVisitor7`
  - `AbstractTypeVisitor8`
  - `AbstractTypeVisitor9`
  - `AbstractTypeVisitor14`

- ## Constructor Summary

  Constructors
  Modifier
  Constructor
  Description
  `protected`
  `AbstractTypeVisitor6()`
  Deprecated.
  Release 6 is obsolete; update to a visitor for a newer release level.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `final R`
  `visit(TypeMirror t)`
  Visits any type mirror as if by passing itself to that type mirror's `accept` method and passing `null` for the additional parameter.
  `final R`
  `visit(TypeMirror t, P p)`
  Visits any type mirror as if by passing itself to that type mirror's `accept` method.
  `R`
  `visitIntersection(IntersectionType t, P p)`
  Visits an intersection type.
  `R`
  `visitUnion(UnionType t, P p)`
  Visits a union type.
  `R`
  `visitUnknown(TypeMirror t, P p)`
  Visits an unknown kind of type.

  ### Methods declared in class Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

  ### Methods declared in interface TypeVisitor

  `visitArray, visitDeclared, visitError, visitExecutable, visitNoType, visitNull, visitPrimitive, visitTypeVariable, visitWildcard`

- ## Constructor Details

  - ### AbstractTypeVisitor6

    @Deprecated(since="9") protected AbstractTypeVisitor6()
    Deprecated.
    Release 6 is obsolete; update to a visitor for a newer release level.
    Constructor for concrete subclasses to call.

- ## Method Details

  - ### visit

    public final R visit(TypeMirror t, P p)
    Visits any type mirror as if by passing itself to that type mirror's `accept` method. The invocation `v.visit(t, p)` is equivalent to `t.accept(v, p)`.
    Specified by:
      `visit` in interface `TypeVisitor<R,P>`
    Parameters:
      `t` - the type to visit
      `p` - a visitor-specified parameter
    Returns:
      a visitor-specified result

  - ### visit

    public final R visit(TypeMirror t)
    Visits any type mirror as if by passing itself to that type mirror's `accept` method and passing `null` for the additional parameter. The invocation `v.visit(t)` is equivalent to `t.accept(v, null)`.
    Specified by:
      `visit` in interface `TypeVisitor<R,P>`
    Parameters:
      `t` - the type to visit
    Returns:
      a visitor-specified result

  - ### visitUnion

    public R visitUnion(UnionType t, P p)
    Visits a union type.
    Specified by:
      `visitUnion` in interface `TypeVisitor<R,P>`
    Implementation Requirements:
      Visits a `UnionType` element by calling `visitUnknown`.
    Parameters:
      `t` - the type to visit
      `p` - a visitor-specified parameter
    Returns:
      the result of `visitUnknown`
    Since:
      1.7

  - ### visitIntersection

    public R visitIntersection(IntersectionType t, P p)
    Visits an intersection type.
    Specified by:
      `visitIntersection` in interface `TypeVisitor<R,P>`
    Implementation Requirements:
      Visits an `IntersectionType` element by calling `visitUnknown`.
    Parameters:
      `t` - the type to visit
      `p` - a visitor-specified parameter
    Returns:
      the result of `visitUnknown`
    Since:
      1.8

  - ### visitUnknown

    public 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 the `TypeMirror` hierarchy.
    Specified by:
      `visitUnknown` in interface `TypeVisitor<R,P>`
    Implementation Requirements:
      The default implementation of this method in `AbstractTypeVisitor6` will always throw `new UnknownTypeException(t, p)`. This behavior is not required of a subclass.
    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