| /* |
| * Copyright (c) 2011, 2014, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package com.sun.source.util; |
| |
| import com.sun.source.doctree.*; |
| |
| |
| /** |
| * 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. |
| * |
| * <p>The default implementation of the visitXYZ methods will determine |
| * a result as follows: |
| * <ul> |
| * <li>If the node being visited has no children, the result will be {@code null}. |
| * <li>If the node being visited has one child, the result will be the |
| * result of calling {@code scan} on that child. The child may be a simple node |
| * or itself a list of nodes. |
| * <li> If the node being visited has more than one child, the result will |
| * be determined by calling {@code scan} 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 {@link #reduce} method. Each child may be either |
| * a simple node of a list of nodes. The default behavior of the {@code reduce} |
| * method is such that the result of the visitXYZ method will be the result of |
| * the last child scanned. |
| * </ul> |
| * |
| * <p>Here is an example to count the number of erroneous nodes in a tree: |
| * <pre> |
| * class CountErrors extends DocTreeScanner<Integer,Void> { |
| * {@literal @}Override |
| * public Integer visitErroneous(ErroneousTree node, Void p) { |
| * return 1; |
| * } |
| * {@literal @}Override |
| * public Integer reduce(Integer r1, Integer r2) { |
| * return (r1 == null ? 0 : r1) + (r2 == null ? 0 : r2); |
| * } |
| * } |
| * </pre> |
| * |
| * @since 1.8 |
| */ |
| @jdk.Exported |
| public class DocTreeScanner<R,P> implements DocTreeVisitor<R,P> { |
| |
| /** |
| * Scans a single node. |
| * @param node the node to be scanned |
| * @param p a parameter value passed to the visit method |
| * @return the result value from the visit method |
| */ |
| public R scan(DocTree node, P p) { |
| return (node == null) ? null : node.accept(this, p); |
| } |
| |
| private R scanAndReduce(DocTree node, P p, R r) { |
| return reduce(scan(node, p), r); |
| } |
| |
| /** |
| * Scans a sequence of nodes. |
| * @param nodes the nodes to be scanned |
| * @param p a parameter value to be passed to the visit method for each node |
| * @return the combined return value from the visit methods. |
| * The values are combined using the {@link #reduce reduce} method. |
| */ |
| public R scan(Iterable<? extends DocTree> nodes, P p) { |
| R r = null; |
| if (nodes != null) { |
| boolean first = true; |
| for (DocTree node : nodes) { |
| r = (first ? scan(node, p) : scanAndReduce(node, p, r)); |
| first = false; |
| } |
| } |
| return r; |
| } |
| |
| private R scanAndReduce(Iterable<? extends DocTree> nodes, P p, R r) { |
| return reduce(scan(nodes, p), r); |
| } |
| |
| /** |
| * 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. |
| * @param r1 the first of the values to be combined |
| * @param r2 the second of the values to be combined |
| * @return the result of combining the two parameters |
| */ |
| public R reduce(R r1, R r2) { |
| return r1; |
| } |
| |
| |
| /* *************************************************************************** |
| * Visitor methods |
| ****************************************************************************/ |
| |
| /** |
| * {@inheritDoc} This implementation returns {@code null}. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitAttribute(AttributeTree node, P p) { |
| return null; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitAuthor(AuthorTree node, P p) { |
| return scan(node.getName(), p); |
| } |
| |
| /** |
| * {@inheritDoc} This implementation returns {@code null}. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitComment(CommentTree node, P p) { |
| return null; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitDeprecated(DeprecatedTree node, P p) { |
| return scan(node.getBody(), p); |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitDocComment(DocCommentTree node, P p) { |
| R r = scan(node.getFirstSentence(), p); |
| r = scanAndReduce(node.getBody(), p, r); |
| r = scanAndReduce(node.getBlockTags(), p, r); |
| return r; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation returns {@code null}. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitDocRoot(DocRootTree node, P p) { |
| return null; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation returns {@code null}. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitEndElement(EndElementTree node, P p) { |
| return null; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation returns {@code null}. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitEntity(EntityTree node, P p) { |
| return null; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation returns {@code null}. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitErroneous(ErroneousTree node, P p) { |
| return null; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation returns {@code null}. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitIdentifier(IdentifierTree node, P p) { |
| return null; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation returns {@code null}. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitInheritDoc(InheritDocTree node, P p) { |
| return null; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitLink(LinkTree node, P p) { |
| R r = scan(node.getReference(), p); |
| r = scanAndReduce(node.getLabel(), p, r); |
| return r; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation returns {@code null}. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitLiteral(LiteralTree node, P p) { |
| return null; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitParam(ParamTree node, P p) { |
| R r = scan(node.getName(), p); |
| r = scanAndReduce(node.getDescription(), p, r); |
| return r; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation returns {@code null}. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitReference(ReferenceTree node, P p) { |
| return null; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitReturn(ReturnTree node, P p) { |
| return scan(node.getDescription(), p); |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitSee(SeeTree node, P p) { |
| return scan(node.getReference(), p); |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitSerial(SerialTree node, P p) { |
| return scan(node.getDescription(), p); |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitSerialData(SerialDataTree node, P p) { |
| return scan(node.getDescription(), p); |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitSerialField(SerialFieldTree node, P p) { |
| R r = scan(node.getName(), p); |
| r = scanAndReduce(node.getType(), p, r); |
| r = scanAndReduce(node.getDescription(), p, r); |
| return r; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitSince(SinceTree node, P p) { |
| return scan(node.getBody(), p); |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitStartElement(StartElementTree node, P p) { |
| return scan(node.getAttributes(), p); |
| } |
| |
| /** |
| * {@inheritDoc} This implementation returns {@code null}. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitText(TextTree node, P p) { |
| return null; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitThrows(ThrowsTree node, P p) { |
| R r = scan(node.getExceptionName(), p); |
| r = scanAndReduce(node.getDescription(), p, r); |
| return r; |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitUnknownBlockTag(UnknownBlockTagTree node, P p) { |
| return scan(node.getContent(), p); |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitUnknownInlineTag(UnknownInlineTagTree node, P p) { |
| return scan(node.getContent(), p); |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitValue(ValueTree node, P p) { |
| return scan(node.getReference(), p); |
| } |
| |
| /** |
| * {@inheritDoc} This implementation scans the children in left to right order. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitVersion(VersionTree node, P p) { |
| return scan(node.getBody(), p); |
| } |
| |
| /** |
| * {@inheritDoc} This implementation returns {@code null}. |
| * |
| * @param node {@inheritDoc} |
| * @param p {@inheritDoc} |
| * @return the result of scanning |
| */ |
| @Override |
| public R visitOther(DocTree node, P p) { |
| return null; |
| } |
| |
| } |
