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.public interface ElementVisitor<R,P>
accept method, the visitXYZ method most applicable
to that element is invoked.
Classes implementing this interface may or may not throw a
NullPointerException if the additional parameter p
is null; 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 extending javax.lang.model.*
to cover Java SE 8 language features. However, default methods may
be used in subsequent revisions of the javax.lang.model.*
packages that are only required to run on Java SE 8 and higher
platform versions.
AbstractElementVisitor6,
AbstractElementVisitor7| Modifier and Type | Method and Description |
|---|---|
R |
visit(Element e)
A convenience method equivalent to
v.visit(e, null). |
R |
visit(Element e,
P p)
Visits an element.
|
R |
visitExecutable(ExecutableElement e,
P p)
Visits an executable element.
|
R |
visitPackage(PackageElement e,
P p)
Visits a package element.
|
R |
visitType(TypeElement e,
P p)
Visits a type element.
|
R |
visitTypeParameter(TypeParameterElement e,
P p)
Visits a type parameter element.
|
R |
visitUnknown(Element e,
P p)
Visits an unknown kind of element.
|
R |
visitVariable(VariableElement e,
P p)
Visits a variable element.
|
R visit(Element e, P p)
e - the element to visitp - a visitor-specified parameterR visit(Element e)
v.visit(e, null).e - the element to visitR visitPackage(PackageElement e, P p)
e - the element to visitp - a visitor-specified parameterR visitType(TypeElement e, P p)
e - the element to visitp - a visitor-specified parameterR visitVariable(VariableElement e, P p)
e - the element to visitp - a visitor-specified parameterR visitExecutable(ExecutableElement e, P p)
e - the element to visitp - a visitor-specified parameterR visitTypeParameter(TypeParameterElement e, P p)
e - the element to visitp - a visitor-specified parameterR visitUnknown(Element e, P p)
Element hierarchy.e - the element to visitp - a visitor-specified parameterUnknownElementException - a visitor implementation may optionally throw this exception 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.
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