Module jdk.compiler
Package com.sun.source.util

Class TreeScanner<R,P>

java.lang.Object
com.sun.source.util.TreeScanner<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:
TreeVisitor<R,P>
Direct Known Subclasses:
TreePathScanner
public class TreeScanner<R,P> extends Object implements TreeVisitor<R,P>
TreeScanner relies on preview features of the Java platform:
Programs can only use TreeScanner when preview features are enabled.
Preview features may be removed in a future release, or upgraded to permanent features of the Java platform.
A TreeVisitor that visits all the child tree nodes. To visit nodes of a particular type, just override the corresponding visitXYZ method. Inside your method, call super.visitXYZ to visit descendant nodes.

Here is an example to count the number of identifier nodes in a tree: 

   class CountIdentifiers extends TreeScanner<Integer,Void> {
      @Override
      public Integer visitIdentifier(IdentifierTree node, Void p) {
          return 1;
      }
      @Override
      public Integer reduce(Integer r1, Integer r2) {
          return (r1 == null ? 0 : r1) + (r2 == null ? 0 : r2);
      }
   }
Implementation Requirements:

The default implementation of the visitXYZ methods will determine a result as follows:

  • If the node being visited has no children, the result will be null.
  • If the node being visited has one child, the result will be the result of calling scan with that child. The child may be a simple node or itself a list of nodes.
  • If the node being visited has more than one child, the result will be determined by calling scan with each child in turn, and then combining the result of each scan after the first with the cumulative result so far, as determined by the reduce(R, R) method. Each child may be either a simple node or a list of nodes. The default behavior of the reduce method is such that the result of the visitXYZ method will be the result of the last child scanned.
Since:
1.6

  • Constructor Details

    • TreeScanner

      public TreeScanner()
      Constructs a TreeScanner.

  • Method Details

    • scan

      public R scan(Tree tree, P p)
      Scans a single node.
      Parameters:
      tree - the node to be scanned
      p - a parameter value passed to the visit method
      Returns:
      the result value from the visit method

    • scan

      public R scan(Iterable<? extends Tree> nodes, P p)
      Scans a sequence of nodes.
      Parameters:
      nodes - the nodes to be scanned
      p - a parameter value to be passed to the visit method for each node
      Returns:
      the combined return value from the visit methods. The values are combined using the reduce method.

    • reduce

      public R reduce(R r1, R r2)
      Reduces two results into a combined result. The default implementation is to return the first parameter. The general contract of the method is that it may take any action whatsoever.
      Parameters:
      r1 - the first of the values to be combined
      r2 - the second of the values to be combined
      Returns:
      the result of combining the two parameters

    • visitCompilationUnit

      public R visitCompilationUnit(CompilationUnitTree node, P p)
      Visits a CompilationUnitTree node.
      Specified by:
      visitCompilationUnit in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitPackage

      public R visitPackage(PackageTree node, P p)
      Visits a PackageTree node.
      Specified by:
      visitPackage in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitImport

      public R visitImport(ImportTree node, P p)
      Visits an ImportTree node.
      Specified by:
      visitImport in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitClass

      public R visitClass(ClassTree node, P p)
      Visits a ClassTree node.
      Specified by:
      visitClass in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitMethod

      public R visitMethod(MethodTree node, P p)
      Visits a MethodTree node.
      Specified by:
      visitMethod in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitVariable

      public R visitVariable(VariableTree node, P p)
      Visits a VariableTree node.
      Specified by:
      visitVariable in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitEmptyStatement

      public R visitEmptyStatement(EmptyStatementTree node, P p)
      Visits an EmptyStatementTree node.
      Specified by:
      visitEmptyStatement in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation returns null.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitBlock

      public R visitBlock(BlockTree node, P p)
      Visits a BlockTree node.
      Specified by:
      visitBlock in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitDoWhileLoop

      public R visitDoWhileLoop(DoWhileLoopTree node, P p)
      Visits a DoWhileTree node.
      Specified by:
      visitDoWhileLoop in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitWhileLoop

      public R visitWhileLoop(WhileLoopTree node, P p)
      Visits a WhileLoopTree node.
      Specified by:
      visitWhileLoop in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitForLoop

      public R visitForLoop(ForLoopTree node, P p)
      Visits a ForLoopTree node.
      Specified by:
      visitForLoop in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitEnhancedForLoop

      public R visitEnhancedForLoop(EnhancedForLoopTree node, P p)
      Visits an EnhancedForLoopTree node.
      Specified by:
      visitEnhancedForLoop in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitLabeledStatement

      public R visitLabeledStatement(LabeledStatementTree node, P p)
      Visits a LabeledStatementTree node.
      Specified by:
      visitLabeledStatement in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitSwitch

      public R visitSwitch(SwitchTree node, P p)
      Visits a SwitchTree node.
      Specified by:
      visitSwitch in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitSwitchExpression

      public R visitSwitchExpression(SwitchExpressionTree node, P p)
      Visits a SwitchExpressionTree node.
      Specified by:
      visitSwitchExpression in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitCase

      public R visitCase(CaseTree node, P p)
      Visits a CaseTree node.
      Specified by:
      visitCase in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitSynchronized

      public R visitSynchronized(SynchronizedTree node, P p)
      Visits a SynchronizedTree node.
      Specified by:
      visitSynchronized in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitTry

      public R visitTry(TryTree node, P p)
      Visits a TryTree node.
      Specified by:
      visitTry in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitCatch

      public R visitCatch(CatchTree node, P p)
      Visits a CatchTree node.
      Specified by:
      visitCatch in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitConditionalExpression

      public R visitConditionalExpression(ConditionalExpressionTree node, P p)
      Visits a ConditionalExpressionTree node.
      Specified by:
      visitConditionalExpression in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitIf

      public R visitIf(IfTree node, P p)
      Visits an IfTree node.
      Specified by:
      visitIf in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitExpressionStatement

      public R visitExpressionStatement(ExpressionStatementTree node, P p)
      Visits an ExpressionStatementTree node.
      Specified by:
      visitExpressionStatement in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitBreak

      public R visitBreak(BreakTree node, P p)
      Visits a BreakTree node.
      Specified by:
      visitBreak in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation returns null.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitContinue

      public R visitContinue(ContinueTree node, P p)
      Visits a ContinueTree node.
      Specified by:
      visitContinue in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation returns null.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitReturn

      public R visitReturn(ReturnTree node, P p)
      Visits a ReturnTree node.
      Specified by:
      visitReturn in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitThrow

      public R visitThrow(ThrowTree node, P p)
      Visits a ThrowTree node.
      Specified by:
      visitThrow in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitAssert

      public R visitAssert(AssertTree node, P p)
      Visits an AssertTree node.
      Specified by:
      visitAssert in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitMethodInvocation

      public R visitMethodInvocation(MethodInvocationTree node, P p)
      Visits a MethodInvocationTree node.
      Specified by:
      visitMethodInvocation in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitNewClass

      public R visitNewClass(NewClassTree node, P p)
      Visits a NewClassTree node.
      Specified by:
      visitNewClass in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitNewArray

      public R visitNewArray(NewArrayTree node, P p)
      Visits a NewArrayTree node.
      Specified by:
      visitNewArray in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitLambdaExpression

      public R visitLambdaExpression(LambdaExpressionTree node, P p)
      Visits a LambdaExpressionTree node.
      Specified by:
      visitLambdaExpression in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitParenthesized

      public R visitParenthesized(ParenthesizedTree node, P p)
      Visits a ParenthesizedTree node.
      Specified by:
      visitParenthesized in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitAssignment

      public R visitAssignment(AssignmentTree node, P p)
      Visits an AssignmentTree node.
      Specified by:
      visitAssignment in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitCompoundAssignment

      public R visitCompoundAssignment(CompoundAssignmentTree node, P p)
      Visits a CompoundAssignmentTree node.
      Specified by:
      visitCompoundAssignment in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitUnary

      public R visitUnary(UnaryTree node, P p)
      Visits a UnaryTree node.
      Specified by:
      visitUnary in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitBinary

      public R visitBinary(BinaryTree node, P p)
      Visits a BinaryTree node.
      Specified by:
      visitBinary in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitTypeCast

      public R visitTypeCast(TypeCastTree node, P p)
      Visits a TypeCastTree node.
      Specified by:
      visitTypeCast in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitInstanceOf

      public R visitInstanceOf(InstanceOfTree node, P p)
      Visits an InstanceOfTree node.
      Specified by:
      visitInstanceOf in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitBindingPattern

      public R visitBindingPattern(BindingPatternTree node, P p)
      Visits an BindingPattern node.
      Specified by:
      visitBindingPattern in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning
      Since:
      14

    • visitDefaultCaseLabel

      public 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.
      Specified by:
      visitDefaultCaseLabel in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation returns null.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning
      Since:
      17

    • visitArrayAccess

      public R visitArrayAccess(ArrayAccessTree node, P p)
      Visits an ArrayAccessTree node.
      Specified by:
      visitArrayAccess in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitMemberSelect

      public R visitMemberSelect(MemberSelectTree node, P p)
      Visits a MemberSelectTree node.
      Specified by:
      visitMemberSelect in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitParenthesizedPattern

      public 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.
      Specified by:
      visitParenthesizedPattern in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning
      Since:
      17

    • visitGuardedPattern

      public 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.
      Specified by:
      visitGuardedPattern in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning
      Since:
      17

    • visitMemberReference

      public R visitMemberReference(MemberReferenceTree node, P p)
      Visits a MemberReferenceTree node.
      Specified by:
      visitMemberReference in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitIdentifier

      public R visitIdentifier(IdentifierTree node, P p)
      Visits an IdentifierTree node.
      Specified by:
      visitIdentifier in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation returns null.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitLiteral

      public R visitLiteral(LiteralTree node, P p)
      Visits a LiteralTree node.
      Specified by:
      visitLiteral in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation returns null.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitPrimitiveType

      public R visitPrimitiveType(PrimitiveTypeTree node, P p)
      Visits a PrimitiveTypeTree node.
      Specified by:
      visitPrimitiveType in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation returns null.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitArrayType

      public R visitArrayType(ArrayTypeTree node, P p)
      Visits an ArrayTypeTree node.
      Specified by:
      visitArrayType in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitParameterizedType

      public R visitParameterizedType(ParameterizedTypeTree node, P p)
      Visits a ParameterizedTypeTree node.
      Specified by:
      visitParameterizedType in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitUnionType

      public R visitUnionType(UnionTypeTree node, P p)
      Visits a UnionTypeTree node.
      Specified by:
      visitUnionType in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitIntersectionType

      public R visitIntersectionType(IntersectionTypeTree node, P p)
      Visits an IntersectionTypeTree node.
      Specified by:
      visitIntersectionType in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitTypeParameter

      public R visitTypeParameter(TypeParameterTree node, P p)
      Visits a TypeParameterTree node.
      Specified by:
      visitTypeParameter in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitWildcard

      public R visitWildcard(WildcardTree node, P p)
      Visits a WildcardTypeTree node.
      Specified by:
      visitWildcard in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitModifiers

      public R visitModifiers(ModifiersTree node, P p)
      Visits a ModifiersTree node.
      Specified by:
      visitModifiers in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitAnnotation

      public R visitAnnotation(AnnotationTree node, P p)
      Visits an AnnotatedTree node.
      Specified by:
      visitAnnotation in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitAnnotatedType

      public R visitAnnotatedType(AnnotatedTypeTree node, P p)
      Visits an AnnotatedTypeTree node.
      Specified by:
      visitAnnotatedType in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitModule

      public R visitModule(ModuleTree node, P p)
      Visits a ModuleTree node.
      Specified by:
      visitModule in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitExports

      public R visitExports(ExportsTree node, P p)
      Visits an ExportsTree node.
      Specified by:
      visitExports in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitOpens

      public R visitOpens(OpensTree node, P p)
      Visits an OpensTree node.
      Specified by:
      visitOpens in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitProvides

      public R visitProvides(ProvidesTree node, P p)
      Visits a ProvidesTree node.
      Specified by:
      visitProvides in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitRequires

      public R visitRequires(RequiresTree node, P p)
      Visits a RequiresTree node.
      Specified by:
      visitRequires in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitUses

      public R visitUses(UsesTree node, P p)
      Visits a UsesTree node.
      Specified by:
      visitUses in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitOther

      public 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.
      Specified by:
      visitOther in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation returns null.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitErroneous

      public R visitErroneous(ErroneousTree node, P p)
      Visits an ErroneousTree node.
      Specified by:
      visitErroneous in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation returns null.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning

    • visitYield

      public R visitYield(YieldTree node, P p)
      Visits a YieldTree node.
      Specified by:
      visitYield in interface TreeVisitor<R,P>
      Implementation Requirements:
      This implementation scans the children in left to right order.
      Parameters:
      node - the node being visited
      p - a parameter value
      Returns:
      the result of scanning