Class DocTreeScanner<R,P>

java.lang.Object

com.sun.source.util.DocTreeScanner<R,P>

All Implemented Interfaces:: DocTreeVisitor<R,P>

Direct Known Subclasses:: DocTreePathScanner

public class DocTreeScanner<R,P> extends Object implements DocTreeVisitor<R,P>

A DocTreeVisitor 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 erroneous nodes in a tree:

   class CountErrors extends DocTreeScanner<Integer,Void> {
      @Override
      public Integer visitErroneous(ErroneousTree 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:

1.8

Constructor Summary

Constructor	Description
`DocTreeScanner()`	Constructs a `DocTreeScanner`.

Method Summary

Modifier and Type	Method	Description
`R`	`reduce(R r1, R r2)`	Reduces two results into a combined result.
`R`	`scan(DocTree node, P p)`	Scans a single node.
`R`	`scan(Iterable<? extends DocTree> nodes, P p)`	Scans a sequence of nodes.
`R`	`visitAttribute(AttributeTree node, P p)`	Visits an AttributeTree node.
`R`	`visitAuthor(AuthorTree node, P p)`	Visits an AuthorTree node.
`R`	`visitComment(CommentTree node, P p)`	Visits a CommentTree node.
`R`	`visitDeprecated(DeprecatedTree node, P p)`	Visits a DeprecatedTree node.
`R`	`visitDocComment(DocCommentTree node, P p)`	Visits a DocCommentTree node.
`R`	`visitDocRoot(DocRootTree node, P p)`	Visits a DocRootTree node.
`R`	`visitDocType(DocTypeTree node, P p)`	Visits a DocTypeTree node.
`R`	`visitEndElement(EndElementTree node, P p)`	Visits an EndElementTree node.
`R`	`visitEntity(EntityTree node, P p)`	Visits an EntityTree node.
`R`	`visitErroneous(ErroneousTree node, P p)`	Visits an ErroneousTree node.
`R`	`visitHidden(HiddenTree node, P p)`	Visits a HiddenTree node.
`R`	`visitIdentifier(IdentifierTree node, P p)`	Visits an IdentifierTree node.
`R`	`visitIndex(IndexTree node, P p)`	Visits an IndexTree node.
`R`	`visitInheritDoc(InheritDocTree node, P p)`	Visits an InheritDocTree node.
`R`	`visitLink(LinkTree node, P p)`	Visits a LinkTree node.
`R`	`visitLiteral(LiteralTree node, P p)`	Visits an LiteralTree node.
`R`	`visitOther(DocTree node, P p)`	Visits an unknown type of DocTree node.
`R`	`visitParam(ParamTree node, P p)`	Visits a ParamTree node.
`R`	`visitProvides(ProvidesTree node, P p)`	Visits a ProvidesTree node.
`R`	`visitReference(ReferenceTree node, P p)`	Visits a ReferenceTree node.
`R`	`visitReturn(ReturnTree node, P p)`	Visits a ReturnTree node.
`R`	`visitSee(SeeTree node, P p)`	Visits a SeeTree node.
`R`	`visitSerial(SerialTree node, P p)`	Visits a SerialTree node.
`R`	`visitSerialData(SerialDataTree node, P p)`	Visits a SerialDataTree node.
`R`	`visitSerialField(SerialFieldTree node, P p)`	Visits a SerialFieldTree node.
`R`	`visitSince(SinceTree node, P p)`	Visits a SinceTree node.
`R`	`visitStartElement(StartElementTree node, P p)`	Visits a StartElementTree node.
`R`	`visitSummary(SummaryTree node, P p)`	Visits a SummaryTree node.
`R`	`visitSystemProperty(SystemPropertyTree node, P p)`	Visits a SystemPropertyTree node.
`R`	`visitText(TextTree node, P p)`	Visits a TextTree node.
`R`	`visitThrows(ThrowsTree node, P p)`	Visits a ThrowsTree node.
`R`	`visitUnknownBlockTag(UnknownBlockTagTree node, P p)`	Visits an UnknownBlockTagTree node.
`R`	`visitUnknownInlineTag(UnknownInlineTagTree node, P p)`	Visits an UnknownInlineTagTree node.
`R`	`visitUses(UsesTree node, P p)`	Visits a UsesTree node.
`R`	`visitValue(ValueTree node, P p)`	Visits a ValueTree node.
`R`	`visitVersion(VersionTree node, P p)`	Visits a VersionTree node.

Methods declared in class java.lang.Object

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

Constructor Details

DocTreeScanner

public DocTreeScanner()

Constructs a DocTreeScanner.

Method Details

scan

public R scan(DocTree node, P p)

Scans a single node.

Parameters:: node - 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 DocTree> 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

visitAttribute

public R visitAttribute(AttributeTree node, P p)

Visits an AttributeTree node.

Specified by:: visitAttribute in interface DocTreeVisitor<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

visitAuthor

public R visitAuthor(AuthorTree node, P p)

Visits an AuthorTree node.

Specified by:: visitAuthor in interface DocTreeVisitor<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

visitComment

public R visitComment(CommentTree node, P p)

Visits a CommentTree node.

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

visitDeprecated

public R visitDeprecated(DeprecatedTree node, P p)

Visits a DeprecatedTree node.

Specified by:: visitDeprecated in interface DocTreeVisitor<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

visitDocComment

public R visitDocComment(DocCommentTree node, P p)

Visits a DocCommentTree node.

Specified by:: visitDocComment in interface DocTreeVisitor<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

visitDocRoot

public R visitDocRoot(DocRootTree node, P p)

Visits a DocRootTree node.

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

visitDocType

public R visitDocType(DocTypeTree node, P p)

Visits a DocTypeTree node.

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

visitEndElement

public R visitEndElement(EndElementTree node, P p)

Visits an EndElementTree node.

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

visitEntity

public R visitEntity(EntityTree node, P p)

Visits an EntityTree node.

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

visitHidden

public R visitHidden(HiddenTree node, P p)

Visits a HiddenTree node.

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

visitIndex

public R visitIndex(IndexTree node, P p)

Visits an IndexTree node.

Specified by:: visitIndex in interface DocTreeVisitor<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

visitInheritDoc

public R visitInheritDoc(InheritDocTree node, P p)

Visits an InheritDocTree node.

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

visitLink

public R visitLink(LinkTree node, P p)

Visits a LinkTree node.

Specified by:: visitLink in interface DocTreeVisitor<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

visitLiteral

public R visitLiteral(LiteralTree node, P p)

Visits an LiteralTree node.

Specified by:: visitLiteral in interface DocTreeVisitor<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

visitParam

public R visitParam(ParamTree node, P p)

Visits a ParamTree node.

Specified by:: visitParam in interface DocTreeVisitor<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 DocTreeVisitor<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

visitReference

public R visitReference(ReferenceTree node, P p)

Visits a ReferenceTree node.

Specified by:: visitReference in interface DocTreeVisitor<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 DocTreeVisitor<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

visitSee

public R visitSee(SeeTree node, P p)

Visits a SeeTree node.

Specified by:: visitSee in interface DocTreeVisitor<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

visitSerial

public R visitSerial(SerialTree node, P p)

Visits a SerialTree node.

Specified by:: visitSerial in interface DocTreeVisitor<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

visitSerialData

public R visitSerialData(SerialDataTree node, P p)

Visits a SerialDataTree node.

Specified by:: visitSerialData in interface DocTreeVisitor<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

visitSerialField

public R visitSerialField(SerialFieldTree node, P p)

Visits a SerialFieldTree node.

Specified by:: visitSerialField in interface DocTreeVisitor<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

visitSince

public R visitSince(SinceTree node, P p)

Visits a SinceTree node.

Specified by:: visitSince in interface DocTreeVisitor<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

visitStartElement

public R visitStartElement(StartElementTree node, P p)

Visits a StartElementTree node.

Specified by:: visitStartElement in interface DocTreeVisitor<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

visitSummary

public R visitSummary(SummaryTree node, P p)

Visits a SummaryTree node.

Specified by:: visitSummary in interface DocTreeVisitor<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:: 10

visitSystemProperty

public R visitSystemProperty(SystemPropertyTree node, P p)

Visits a SystemPropertyTree node.

Specified by:: visitSystemProperty in interface DocTreeVisitor<R,P>
Implementation Requirements:: This implementation returns null.
Parameters:: node - the node being visited; p - a parameter value
Returns:: the result of scanning
Since:: 12

visitText

public R visitText(TextTree node, P p)

Visits a TextTree node.

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

visitThrows

public R visitThrows(ThrowsTree node, P p)

Visits a ThrowsTree node.

Specified by:: visitThrows in interface DocTreeVisitor<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

visitUnknownBlockTag

public R visitUnknownBlockTag(UnknownBlockTagTree node, P p)

Visits an UnknownBlockTagTree node.

Specified by:: visitUnknownBlockTag in interface DocTreeVisitor<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

visitUnknownInlineTag

public R visitUnknownInlineTag(UnknownInlineTagTree node, P p)

Visits an UnknownInlineTagTree node.

Specified by:: visitUnknownInlineTag in interface DocTreeVisitor<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 DocTreeVisitor<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

visitValue

public R visitValue(ValueTree node, P p)

Visits a ValueTree node.

Specified by:: visitValue in interface DocTreeVisitor<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

visitVersion

public R visitVersion(VersionTree node, P p)

Visits a VersionTree node.

Specified by:: visitVersion in interface DocTreeVisitor<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(DocTree node, P p)

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

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

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