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package com.sun.source.tree;

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.

Author:Peter von der Ahé, Jonathan Gibbons
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.
Since:1.6
/** * 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 {@link Tree#accept * accept} method, the <code>visit<i>Xyz</i></code> method most applicable * to that tree is invoked. * * <p> Classes implementing this interface may or may not throw a * {@code NullPointerException} if the additional parameter {@code p} * is {@code null}; see documentation of the implementing class for * details. * * <p> <b>WARNING:</b> 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&trade; programming * language. Therefore, visitor classes directly implementing this * interface may be source incompatible with future versions of the * platform. * * @param <R> the return type of this visitor's methods. Use {@link * Void} for visitors that do not need to return results. * @param <P> the type of the additional parameter to this visitor's * methods. Use {@code Void} for visitors that do not need an * additional parameter. * * @author Peter von der Ah&eacute; * @author Jonathan Gibbons * * @since 1.6 */
public interface TreeVisitor<R,P> {
Visits an AnnotatedTypeTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an AnnotatedTypeTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitAnnotatedType(AnnotatedTypeTree node, P p);
Visits an AnnotatedTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an AnnotatedTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitAnnotation(AnnotationTree node, P p);
Visits a MethodInvocationTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a MethodInvocationTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitMethodInvocation(MethodInvocationTree node, P p);
Visits an AssertTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an AssertTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitAssert(AssertTree node, P p);
Visits an AssignmentTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an AssignmentTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitAssignment(AssignmentTree node, P p);
Visits a CompoundAssignmentTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a CompoundAssignmentTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitCompoundAssignment(CompoundAssignmentTree node, P p);
Visits a BinaryTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a BinaryTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitBinary(BinaryTree node, P p);
Visits a BlockTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a BlockTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitBlock(BlockTree node, P p);
Visits a BreakTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a BreakTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitBreak(BreakTree node, P p);
Visits a CaseTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a CaseTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitCase(CaseTree node, P p);
Visits a CatchTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a CatchTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitCatch(CatchTree node, P p);
Visits a ClassTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a ClassTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitClass(ClassTree node, P p);
Visits a ConditionalExpressionTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a ConditionalExpressionTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitConditionalExpression(ConditionalExpressionTree node, P p);
Visits a ContinueTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a ContinueTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitContinue(ContinueTree node, P p);
Visits a DoWhileTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a DoWhileTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitDoWhileLoop(DoWhileLoopTree node, P p);
Visits an ErroneousTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an ErroneousTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitErroneous(ErroneousTree node, P p);
Visits an ExpressionStatementTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an ExpressionStatementTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitExpressionStatement(ExpressionStatementTree node, P p);
Visits an EnhancedForLoopTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an EnhancedForLoopTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitEnhancedForLoop(EnhancedForLoopTree node, P p);
Visits a ForLoopTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a ForLoopTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitForLoop(ForLoopTree node, P p);
Visits an IdentifierTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an IdentifierTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitIdentifier(IdentifierTree node, P p);
Visits an IfTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an IfTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitIf(IfTree node, P p);
Visits an ImportTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an ImportTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitImport(ImportTree node, P p);
Visits an ArrayAccessTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an ArrayAccessTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitArrayAccess(ArrayAccessTree node, P p);
Visits a LabeledStatementTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a LabeledStatementTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitLabeledStatement(LabeledStatementTree node, P p);
Visits a LiteralTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a LiteralTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitLiteral(LiteralTree node, P p);
{@preview Associated with pattern matching for instanceof, a preview feature of the Java language. This method is associated with pattern matching for instanceof, a preview feature of the Java language. Preview features may be removed in a future release, or upgraded to permanent features of the Java language.} Visits an BindingPattern node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
Since:14
/** * {@preview Associated with pattern matching for instanceof, a preview feature of * the Java language. * * This method is associated with <i>pattern matching for instanceof</i>, a preview * feature of the Java language. Preview features * may be removed in a future release, or upgraded to permanent * features of the Java language.} * * Visits an BindingPattern node. * @param node the node being visited * @param p a parameter value * @return a result value * @since 14 */
R visitBindingPattern(BindingPatternTree node, P p);
Visits a MethodTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a MethodTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitMethod(MethodTree node, P p);
Visits a ModifiersTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a ModifiersTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitModifiers(ModifiersTree node, P p);
Visits a NewArrayTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a NewArrayTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitNewArray(NewArrayTree node, P p);
Visits a NewClassTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a NewClassTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitNewClass(NewClassTree node, P p);
Visits a LambdaExpressionTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a LambdaExpressionTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitLambdaExpression(LambdaExpressionTree node, P p);
Visits a PackageTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a PackageTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitPackage(PackageTree node, P p);
Visits a ParenthesizedTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a ParenthesizedTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitParenthesized(ParenthesizedTree node, P p);
Visits a ReturnTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a ReturnTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitReturn(ReturnTree node, P p);
Visits a MemberSelectTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a MemberSelectTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitMemberSelect(MemberSelectTree node, P p);
Visits a MemberReferenceTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a MemberReferenceTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitMemberReference(MemberReferenceTree node, P p);
Visits an EmptyStatementTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an EmptyStatementTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitEmptyStatement(EmptyStatementTree node, P p);
Visits a SwitchTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a SwitchTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitSwitch(SwitchTree node, P p);
Visits a SwitchExpressionTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
Since:12
/** * Visits a SwitchExpressionTree node. * * @param node the node being visited * @param p a parameter value * @return a result value * @since 12 */
R visitSwitchExpression(SwitchExpressionTree node, P p);
Visits a SynchronizedTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a SynchronizedTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitSynchronized(SynchronizedTree node, P p);
Visits a ThrowTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a ThrowTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitThrow(ThrowTree node, P p);
Visits a CompilationUnitTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a CompilationUnitTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitCompilationUnit(CompilationUnitTree node, P p);
Visits a TryTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a TryTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitTry(TryTree node, P p);
Visits a ParameterizedTypeTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a ParameterizedTypeTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitParameterizedType(ParameterizedTypeTree node, P p);
Visits a UnionTypeTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a UnionTypeTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitUnionType(UnionTypeTree node, P p);
Visits an IntersectionTypeTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an IntersectionTypeTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitIntersectionType(IntersectionTypeTree node, P p);
Visits an ArrayTypeTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an ArrayTypeTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitArrayType(ArrayTypeTree node, P p);
Visits a TypeCastTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a TypeCastTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitTypeCast(TypeCastTree node, P p);
Visits a PrimitiveTypeTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a PrimitiveTypeTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitPrimitiveType(PrimitiveTypeTree node, P p);
Visits a TypeParameterTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a TypeParameterTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitTypeParameter(TypeParameterTree node, P p);
Visits an InstanceOfTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an InstanceOfTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitInstanceOf(InstanceOfTree node, P p);
Visits a UnaryTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a UnaryTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitUnary(UnaryTree node, P p);
Visits a VariableTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a VariableTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitVariable(VariableTree node, P p);
Visits a WhileLoopTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a WhileLoopTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitWhileLoop(WhileLoopTree node, P p);
Visits a WildcardTypeTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a WildcardTypeTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitWildcard(WildcardTree node, P p);
Visits a ModuleTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a ModuleTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitModule(ModuleTree node, P p);
Visits an ExportsTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an ExportsTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitExports(ExportsTree node, P p);
Visits an OpensTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an OpensTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitOpens(OpensTree node, P p);
Visits a ProvidesTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a ProvidesTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitProvides(ProvidesTree node, P p);
Visits a RequiresTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a RequiresTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitRequires(RequiresTree node, P p);
Visits a UsesTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits a UsesTree node. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitUses(UsesTree 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.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
/** * Visits an unknown type of Tree node. * This can occur if the language evolves and new kinds * of nodes are added to the {@code Tree} hierarchy. * @param node the node being visited * @param p a parameter value * @return a result value */
R visitOther(Tree node, P p);
Visits a YieldTree node.
Params:
  • node – the node being visited
  • p – a parameter value
Returns:a result value
Since:13
/** * Visits a YieldTree node. * @param node the node being visited * @param p a parameter value * @return a result value * @since 13 */
R visitYield(YieldTree node, P p); }