| /* |
| * Copyright (c) 2006, 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 java.util.Iterator; |
| import java.util.Objects; |
| |
| import com.sun.source.tree.*; |
| |
| /** |
| * A path of tree nodes, typically used to represent the sequence of ancestor |
| * nodes of a tree node up to the top level CompilationUnitTree node. |
| * |
| * @author Jonathan Gibbons |
| * @since 1.6 |
| */ |
| @jdk.Exported |
| public class TreePath implements Iterable<Tree> { |
| /** |
| * Returns a tree path for a tree node within a compilation unit, |
| * or {@code null} if the node is not found. |
| * @param unit the compilation unit to search |
| * @param target the node to locate |
| * @return the tree path |
| */ |
| public static TreePath getPath(CompilationUnitTree unit, Tree target) { |
| return getPath(new TreePath(unit), target); |
| } |
| |
| /** |
| * Returns a tree path for a tree node within a subtree identified by a TreePath object. |
| * Returns {@code null} if the node is not found. |
| * @param path the path in which to search |
| * @param target the node to locate |
| * @return the tree path of the target node |
| */ |
| public static TreePath getPath(TreePath path, Tree target) { |
| Objects.requireNonNull(path); |
| Objects.requireNonNull(target); |
| |
| class Result extends Error { |
| static final long serialVersionUID = -5942088234594905625L; |
| TreePath path; |
| Result(TreePath path) { |
| this.path = path; |
| } |
| } |
| |
| class PathFinder extends TreePathScanner<TreePath,Tree> { |
| public TreePath scan(Tree tree, Tree target) { |
| if (tree == target) { |
| throw new Result(new TreePath(getCurrentPath(), target)); |
| } |
| return super.scan(tree, target); |
| } |
| } |
| |
| if (path.getLeaf() == target) { |
| return path; |
| } |
| |
| try { |
| new PathFinder().scan(path, target); |
| } catch (Result result) { |
| return result.path; |
| } |
| return null; |
| } |
| |
| /** |
| * Creates a TreePath for a root node. |
| * @param node the root node |
| */ |
| public TreePath(CompilationUnitTree node) { |
| this(null, node); |
| } |
| |
| /** |
| * Creates a TreePath for a child node. |
| * @param path the parent path |
| * @param tree the child node |
| */ |
| public TreePath(TreePath path, Tree tree) { |
| if (tree.getKind() == Tree.Kind.COMPILATION_UNIT) { |
| compilationUnit = (CompilationUnitTree) tree; |
| parent = null; |
| } |
| else { |
| compilationUnit = path.compilationUnit; |
| parent = path; |
| } |
| leaf = tree; |
| } |
| /** |
| * Returns the compilation unit associated with this path. |
| * @return the compilation unit |
| */ |
| public CompilationUnitTree getCompilationUnit() { |
| return compilationUnit; |
| } |
| |
| /** |
| * Returns the leaf node for this path. |
| * @return the leaf node |
| */ |
| public Tree getLeaf() { |
| return leaf; |
| } |
| |
| /** |
| * Returns the path for the enclosing node, or {@code null} if there is no enclosing node. |
| * @return the path for the enclosing node |
| */ |
| public TreePath getParentPath() { |
| return parent; |
| } |
| |
| /** |
| * Iterates from leaves to root. |
| */ |
| @Override |
| public Iterator<Tree> iterator() { |
| return new Iterator<Tree>() { |
| @Override |
| public boolean hasNext() { |
| return next != null; |
| } |
| |
| @Override |
| public Tree next() { |
| Tree t = next.leaf; |
| next = next.parent; |
| return t; |
| } |
| |
| @Override |
| public void remove() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| private TreePath next = TreePath.this; |
| }; |
| } |
| |
| private CompilationUnitTree compilationUnit; |
| private Tree leaf; |
| private TreePath parent; |
| } |