Interface TreeVisitor<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 Known Implementing Classes:: SimpleTreeVisitor, TreePathScanner, TreeScanner

public interface TreeVisitor<R,P>

TreeVisitor relies on preview features of the Java platform:

TreeVisitor refers to one or more reflective preview APIs: DefaultCaseLabelTree, GuardedPatternTree, ParenthesizedPatternTree.

Programs can only use TreeVisitor when preview features are enabled.

Preview features may be removed in a future release, or upgraded to permanent features of the Java platform.

A visitor of trees, in the style of the visitor design pattern. Classes implementing this interface are used to operate on a tree when the kind of tree is unknown at compile time. When a visitor is passed to an tree's accept method, the visitXyz method most applicable to that tree 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.

Since:: 1.6

Method Summary

Modifier and Type	Method	Description
`R`	`visitAnnotatedType(AnnotatedTypeTree node, P p)`	Visits an AnnotatedTypeTree node.
`R`	`visitAnnotation(AnnotationTree node, P p)`	Visits an AnnotatedTree node.
`R`	`visitArrayAccess(ArrayAccessTree node, P p)`	Visits an ArrayAccessTree node.
`R`	`visitArrayType(ArrayTypeTree node, P p)`	Visits an ArrayTypeTree node.
`R`	`visitAssert(AssertTree node, P p)`	Visits an AssertTree node.
`R`	`visitAssignment(AssignmentTree node, P p)`	Visits an AssignmentTree node.
`R`	`visitBinary(BinaryTree node, P p)`	Visits a BinaryTree node.
`R`	`visitBindingPattern(BindingPatternTree node, P p)`	Visits an BindingPattern node.
`R`	`visitBlock(BlockTree node, P p)`	Visits a BlockTree node.
`R`	`visitBreak(BreakTree node, P p)`	Visits a BreakTree node.
`R`	`visitCase(CaseTree node, P p)`	Visits a CaseTree node.
`R`	`visitCatch(CatchTree node, P p)`	Visits a CatchTree node.
`R`	`visitClass(ClassTree node, P p)`	Visits a ClassTree node.
`R`	`visitCompilationUnit(CompilationUnitTree node, P p)`	Visits a CompilationUnitTree node.
`R`	`visitCompoundAssignment(CompoundAssignmentTree node, P p)`	Visits a CompoundAssignmentTree node.
`R`	`visitConditionalExpression(ConditionalExpressionTree node, P p)`	Visits a ConditionalExpressionTree node.
`R`	`visitContinue(ContinueTree node, P p)`	Visits a ContinueTree node.
`R`	`visitDefaultCaseLabel(DefaultCaseLabelTree^PREVIEW node, P p)`	Preview. Visits a DefaultCaseLabelTree node.
`R`	`visitDoWhileLoop(DoWhileLoopTree node, P p)`	Visits a DoWhileTree node.
`R`	`visitEmptyStatement(EmptyStatementTree node, P p)`	Visits an EmptyStatementTree node.
`R`	`visitEnhancedForLoop(EnhancedForLoopTree node, P p)`	Visits an EnhancedForLoopTree node.
`R`	`visitErroneous(ErroneousTree node, P p)`	Visits an ErroneousTree node.
`R`	`visitExports(ExportsTree node, P p)`	Visits an ExportsTree node.
`R`	`visitExpressionStatement(ExpressionStatementTree node, P p)`	Visits an ExpressionStatementTree node.
`R`	`visitForLoop(ForLoopTree node, P p)`	Visits a ForLoopTree node.
`R`	`visitGuardedPattern(GuardedPatternTree^PREVIEW node, P p)`	Preview. Visits a GuardPatternTree node.
`R`	`visitIdentifier(IdentifierTree node, P p)`	Visits an IdentifierTree node.
`R`	`visitIf(IfTree node, P p)`	Visits an IfTree node.
`R`	`visitImport(ImportTree node, P p)`	Visits an ImportTree node.
`R`	`visitInstanceOf(InstanceOfTree node, P p)`	Visits an InstanceOfTree node.
`R`	`visitIntersectionType(IntersectionTypeTree node, P p)`	Visits an IntersectionTypeTree node.
`R`	`visitLabeledStatement(LabeledStatementTree node, P p)`	Visits a LabeledStatementTree node.
`R`	`visitLambdaExpression(LambdaExpressionTree node, P p)`	Visits a LambdaExpressionTree node.
`R`	`visitLiteral(LiteralTree node, P p)`	Visits a LiteralTree node.
`R`	`visitMemberReference(MemberReferenceTree node, P p)`	Visits a MemberReferenceTree node.
`R`	`visitMemberSelect(MemberSelectTree node, P p)`	Visits a MemberSelectTree node.
`R`	`visitMethod(MethodTree node, P p)`	Visits a MethodTree node.
`R`	`visitMethodInvocation(MethodInvocationTree node, P p)`	Visits a MethodInvocationTree node.
`R`	`visitModifiers(ModifiersTree node, P p)`	Visits a ModifiersTree node.
`R`	`visitModule(ModuleTree node, P p)`	Visits a ModuleTree node.
`R`	`visitNewArray(NewArrayTree node, P p)`	Visits a NewArrayTree node.
`R`	`visitNewClass(NewClassTree node, P p)`	Visits a NewClassTree node.
`R`	`visitOpens(OpensTree node, P p)`	Visits an OpensTree node.
`R`	`visitOther(Tree node, P p)`	Visits an unknown type of Tree node.
`R`	`visitPackage(PackageTree node, P p)`	Visits a PackageTree node.
`R`	`visitParameterizedType(ParameterizedTypeTree node, P p)`	Visits a ParameterizedTypeTree node.
`R`	`visitParenthesized(ParenthesizedTree node, P p)`	Visits a ParenthesizedTree node.
`R`	`visitParenthesizedPattern(ParenthesizedPatternTree^PREVIEW node, P p)`	Preview. Visits a ParenthesizedPatternTree node.
`R`	`visitPrimitiveType(PrimitiveTypeTree node, P p)`	Visits a PrimitiveTypeTree node.
`R`	`visitProvides(ProvidesTree node, P p)`	Visits a ProvidesTree node.
`R`	`visitRequires(RequiresTree node, P p)`	Visits a RequiresTree node.
`R`	`visitReturn(ReturnTree node, P p)`	Visits a ReturnTree node.
`R`	`visitSwitch(SwitchTree node, P p)`	Visits a SwitchTree node.
`R`	`visitSwitchExpression(SwitchExpressionTree node, P p)`	Visits a SwitchExpressionTree node.
`R`	`visitSynchronized(SynchronizedTree node, P p)`	Visits a SynchronizedTree node.
`R`	`visitThrow(ThrowTree node, P p)`	Visits a ThrowTree node.
`R`	`visitTry(TryTree node, P p)`	Visits a TryTree node.
`R`	`visitTypeCast(TypeCastTree node, P p)`	Visits a TypeCastTree node.
`R`	`visitTypeParameter(TypeParameterTree node, P p)`	Visits a TypeParameterTree node.
`R`	`visitUnary(UnaryTree node, P p)`	Visits a UnaryTree node.
`R`	`visitUnionType(UnionTypeTree node, P p)`	Visits a UnionTypeTree node.
`R`	`visitUses(UsesTree node, P p)`	Visits a UsesTree node.
`R`	`visitVariable(VariableTree node, P p)`	Visits a VariableTree node.
`R`	`visitWhileLoop(WhileLoopTree node, P p)`	Visits a WhileLoopTree node.
`R`	`visitWildcard(WildcardTree node, P p)`	Visits a WildcardTypeTree node.
`R`	`visitYield(YieldTree node, P p)`	Visits a YieldTree node.

Method Details

visitAnnotatedType

R visitAnnotatedType(AnnotatedTypeTree node, P p)

Visits an AnnotatedTypeTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitAnnotation

R visitAnnotation(AnnotationTree node, P p)

Visits an AnnotatedTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitMethodInvocation

R visitMethodInvocation(MethodInvocationTree node, P p)

Visits a MethodInvocationTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitAssert

R visitAssert(AssertTree node, P p)

Visits an AssertTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitAssignment

R visitAssignment(AssignmentTree node, P p)

Visits an AssignmentTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitCompoundAssignment

R visitCompoundAssignment(CompoundAssignmentTree node, P p)

Visits a CompoundAssignmentTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitBinary

R visitBinary(BinaryTree node, P p)

Visits a BinaryTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitBlock

R visitBlock(BlockTree node, P p)

Visits a BlockTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitBreak

R visitBreak(BreakTree node, P p)

Visits a BreakTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitCase

R visitCase(CaseTree node, P p)

Visits a CaseTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitCatch

R visitCatch(CatchTree node, P p)

Visits a CatchTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitClass

R visitClass(ClassTree node, P p)

Visits a ClassTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitConditionalExpression

R visitConditionalExpression(ConditionalExpressionTree node, P p)

Visits a ConditionalExpressionTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitContinue

R visitContinue(ContinueTree node, P p)

Visits a ContinueTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitDoWhileLoop

R visitDoWhileLoop(DoWhileLoopTree node, P p)

Visits a DoWhileTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitErroneous

R visitErroneous(ErroneousTree node, P p)

Visits an ErroneousTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitExpressionStatement

R visitExpressionStatement(ExpressionStatementTree node, P p)

Visits an ExpressionStatementTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitEnhancedForLoop

R visitEnhancedForLoop(EnhancedForLoopTree node, P p)

Visits an EnhancedForLoopTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitForLoop

R visitForLoop(ForLoopTree node, P p)

Visits a ForLoopTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitIdentifier

R visitIdentifier(IdentifierTree node, P p)

Visits an IdentifierTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitIf

R visitIf(IfTree node, P p)

Visits an IfTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitImport

R visitImport(ImportTree node, P p)

Visits an ImportTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitArrayAccess

R visitArrayAccess(ArrayAccessTree node, P p)

Visits an ArrayAccessTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitLabeledStatement

R visitLabeledStatement(LabeledStatementTree node, P p)

Visits a LabeledStatementTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitLiteral

R visitLiteral(LiteralTree node, P p)

Visits a LiteralTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitBindingPattern

R visitBindingPattern(BindingPatternTree node, P p)

Visits an BindingPattern node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value
Since:: 16

visitDefaultCaseLabel

R visitDefaultCaseLabel(DefaultCaseLabelTreePREVIEW node, P p)

visitDefaultCaseLabel is a reflective preview API of the Java platform.

Preview features may be removed in a future release, or upgraded to permanent features of the Java platform.

Visits a DefaultCaseLabelTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value
Since:: 17

visitMethod

R visitMethod(MethodTree node, P p)

Visits a MethodTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitModifiers

R visitModifiers(ModifiersTree node, P p)

Visits a ModifiersTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitNewArray

R visitNewArray(NewArrayTree node, P p)

Visits a NewArrayTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitGuardedPattern

R visitGuardedPattern(GuardedPatternTreePREVIEW node, P p)

visitGuardedPattern is a reflective preview API of the Java platform.

Preview features may be removed in a future release, or upgraded to permanent features of the Java platform.

Visits a GuardPatternTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value
Since:: 17

visitParenthesizedPattern

R visitParenthesizedPattern(ParenthesizedPatternTreePREVIEW node, P p)

visitParenthesizedPattern is a reflective preview API of the Java platform.

Preview features may be removed in a future release, or upgraded to permanent features of the Java platform.

Visits a ParenthesizedPatternTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value
Since:: 17

visitNewClass

R visitNewClass(NewClassTree node, P p)

Visits a NewClassTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitLambdaExpression

R visitLambdaExpression(LambdaExpressionTree node, P p)

Visits a LambdaExpressionTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitPackage

R visitPackage(PackageTree node, P p)

Visits a PackageTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitParenthesized

R visitParenthesized(ParenthesizedTree node, P p)

Visits a ParenthesizedTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitReturn

R visitReturn(ReturnTree node, P p)

Visits a ReturnTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitMemberSelect

R visitMemberSelect(MemberSelectTree node, P p)

Visits a MemberSelectTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitMemberReference

R visitMemberReference(MemberReferenceTree node, P p)

Visits a MemberReferenceTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitEmptyStatement

R visitEmptyStatement(EmptyStatementTree node, P p)

Visits an EmptyStatementTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitSwitch

R visitSwitch(SwitchTree node, P p)

Visits a SwitchTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitSwitchExpression

R visitSwitchExpression(SwitchExpressionTree node, P p)

Visits a SwitchExpressionTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value
Since:: 12

visitSynchronized

R visitSynchronized(SynchronizedTree node, P p)

Visits a SynchronizedTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitThrow

R visitThrow(ThrowTree node, P p)

Visits a ThrowTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitCompilationUnit

R visitCompilationUnit(CompilationUnitTree node, P p)

Visits a CompilationUnitTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitTry

R visitTry(TryTree node, P p)

Visits a TryTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitParameterizedType

R visitParameterizedType(ParameterizedTypeTree node, P p)

Visits a ParameterizedTypeTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitUnionType

R visitUnionType(UnionTypeTree node, P p)

Visits a UnionTypeTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitIntersectionType

R visitIntersectionType(IntersectionTypeTree node, P p)

Visits an IntersectionTypeTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitArrayType

R visitArrayType(ArrayTypeTree node, P p)

Visits an ArrayTypeTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitTypeCast

R visitTypeCast(TypeCastTree node, P p)

Visits a TypeCastTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitPrimitiveType

R visitPrimitiveType(PrimitiveTypeTree node, P p)

Visits a PrimitiveTypeTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitTypeParameter

R visitTypeParameter(TypeParameterTree node, P p)

Visits a TypeParameterTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitInstanceOf

R visitInstanceOf(InstanceOfTree node, P p)

Visits an InstanceOfTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitUnary

R visitUnary(UnaryTree node, P p)

Visits a UnaryTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitVariable

R visitVariable(VariableTree node, P p)

Visits a VariableTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitWhileLoop

R visitWhileLoop(WhileLoopTree node, P p)

Visits a WhileLoopTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitWildcard

R visitWildcard(WildcardTree node, P p)

Visits a WildcardTypeTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitModule

R visitModule(ModuleTree node, P p)

Visits a ModuleTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitExports

R visitExports(ExportsTree node, P p)

Visits an ExportsTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitOpens

R visitOpens(OpensTree node, P p)

Visits an OpensTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitProvides

R visitProvides(ProvidesTree node, P p)

Visits a ProvidesTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitRequires

R visitRequires(RequiresTree node, P p)

Visits a RequiresTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitUses

R visitUses(UsesTree node, P p)

Visits a UsesTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitOther

R visitOther(Tree node, P p)

Visits an unknown type of Tree node. This can occur if the language evolves and new kinds of nodes are added to the Tree hierarchy.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value

visitYield

R visitYield(YieldTree node, P p)

Visits a YieldTree node.

Parameters:: node - the node being visited; p - a parameter value
Returns:: a result value
Since:: 13

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https://docs.oracle.com/en/java/javase/17/docs/api/jdk.compiler/com/sun/source/tree/TreeVisitor.html