/*

 * Copyright (c) 2005, 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.tree.*;

/**

 * Provides methods to obtain the position of a Tree within a CompilationUnit.

 * A position is defined as a simple character offset from the start of a

 * CompilationUnit where the first character is at offset 0.

 *

 * @author Peter von der Ahé

 * @since 1.6

 */

public interface SourcePositions {

    /**

     * Returns the starting position of tree within file.  If tree is not found within

     * file, or if the starting position is not available,

     * return {@link javax.tools.Diagnostic#NOPOS}.

     * The returned position must be at the start of the yield of this tree, that

     * is for any sub-tree of this tree, the following must hold:

     *

     * <p>

     * {@code tree.getStartPosition() <= subtree.getStartPosition()} or <br>

     * {@code tree.getStartPosition() == NOPOS} or <br>

     * {@code subtree.getStartPosition() == NOPOS}

     * </p>

     *

     * @param file CompilationUnit in which to find tree.

     * @param tree tree for which a position is sought.

     * @return the start position of tree.

     */

     long getStartPosition(CompilationUnitTree file, Tree tree);

    /**

     * Returns the ending position of tree within file.  If tree is not found within

     * file, or if the ending position is not available,

     * return {@link javax.tools.Diagnostic#NOPOS}.

     * The returned position must be at the end of the yield of this tree,

     * that is for any sub-tree of this tree, the following must hold:

     *

     * <p>

     * {@code tree.getEndPosition() >= subtree.getEndPosition()} or <br>

     * {@code tree.getEndPosition() == NOPOS} or <br>

     * {@code subtree.getEndPosition() == NOPOS}

     * </p>

     *

     * In addition, the following must hold:

     *

     * <p>

     * {@code tree.getStartPosition() <= tree.getEndPosition()}  or <br>

     * {@code tree.getStartPosition() == NOPOS} or <br>

     * {@code tree.getEndPosition() == NOPOS}

     * </p>

     *

     * @param file CompilationUnit in which to find tree.

     * @param tree tree for which a position is sought.

     * @return the end position of tree.

     */

     long getEndPosition(CompilationUnitTree file, Tree tree);

}