/*
* Copyright 2006 Sun Microsystems, Inc. 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. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package com.sun.source.util;
import com.sun.source.tree.*;
/**
* A TreeVisitor that visits all the child tree nodes, and provides
* support for maintaining a path for the parent nodes.
* To visit nodes of a particular type, just override the
* corresponding visitorXYZ method.
* Inside your method, call super.visitXYZ to visit descendant
* nodes.
*
* @author Jonathan Gibbons
* @since 1.6
*/
public class TreePathScanner<R, P> extends TreeScanner<R, P> {
/**
* Scan a tree from a position identified by a TreePath.
*/
public R scan(TreePath path, P p) {
this.path = path;
try {
return path.getLeaf().accept(this, p);
} finally {
this.path = null;
}
}
/**
* Scan a single node.
* The current path is updated for the duration of the scan.
*/
@Override
public R scan(Tree tree, P p) {
if (tree == null)
return null;
TreePath prev = path;
path = new TreePath(path, tree);
try {
return tree.accept(this, p);
} finally {
path = prev;
}
}
/**
* Get the current path for the node, as built up by the currently
* active set of scan calls.
*/
public TreePath getCurrentPath() {
return path;
}
private TreePath path;
}
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