1 /*
   2  * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package com.sun.source.util;
  27 
  28 import com.sun.source.tree.*;
  29 
  30 /**
  31  * Provides methods to obtain the position of a Tree within a CompilationUnit.
  32  * A position is defined as a simple character offset from the start of a
  33  * CompilationUnit where the first character is at offset 0.
  34  *
  35  * @author Peter von der Ahé
  36  * @since 1.6
  37  */
  38 @jdk.Supported
  39 public interface SourcePositions {
  40 
  41     /**
  42      * Gets the starting position of tree within file.  If tree is not found within
  43      * file, or if the starting position is not available,
  44      * return {@link javax.tools.Diagnostic#NOPOS}.
  45      * The returned position must be at the start of the yield of this tree, that
  46      * is for any sub-tree of this tree, the following must hold:
  47      *
  48      * <p>
  49      * {@code tree.getStartPosition() <= subtree.getStartPosition()} or <br>
  50      * {@code tree.getStartPosition() == NOPOS} or <br>
  51      * {@code subtree.getStartPosition() == NOPOS}
  52      * </p>
  53      *
  54      * @param file CompilationUnit in which to find tree.
  55      * @param tree tree for which a position is sought.
  56      * @return the start position of tree.
  57      */
  58      long getStartPosition(CompilationUnitTree file, Tree tree);
  59 
  60     /**
  61      * Gets the ending position of tree within file.  If tree is not found within
  62      * file, or if the starting position is not available,
  63      * return {@link javax.tools.Diagnostic#NOPOS}.
  64      * The returned position must be at the end of the yield of this tree,
  65      * that is for any sub-tree of this tree, the following must hold:
  66      *
  67      * <p>
  68      * {@code tree.getEndPosition() >= subtree.getEndPosition()} or <br>
  69      * {@code tree.getEndPosition() == NOPOS} or <br>
  70      * {@code subtree.getEndPosition() == NOPOS}
  71      * </p>
  72      *
  73      * In addition, the following must hold:
  74      *
  75      * <p>
  76      * {@code tree.getStartPosition() <= tree.getEndPosition()}  or <br>
  77      * {@code tree.getStartPosition() == NOPOS} or <br>
  78      * {@code tree.getEndPosition() == NOPOS}
  79      * </p>
  80      *
  81      * @param file CompilationUnit in which to find tree.
  82      * @param tree tree for which a position is sought.
  83      * @return the end position of tree.
  84      */
  85      long getEndPosition(CompilationUnitTree file, Tree tree);
  86 
  87 }