/*

 * 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

 * particular file as subject to the "Classpath" exception as provided

 *

 * 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.

 *

 */

package com.sun.source.tree;

/**

 * Provides methods to convert between character positions and line numbers

 * for a compilation unit.

 *

 * @since 1.6

 */

public interface LineMap {

    /**

     * Find the start position of a line.

     *

     * @param line line number (beginning at 1)

     * @return     position of first character in line

     * @throws  IndexOutOfBoundsException

     *           if <tt>lineNumber < 1</tt>

     *           if <tt>lineNumber > no. of lines</tt>

     */

    long getStartPosition(long line);

    /**

     * Find the position corresponding to a (line,column).

     *

     * @param   line    line number (beginning at 1)

     * @param   column  tab-expanded column number (beginning 1)

     *

     * @return  position of character

     * @throws  IndexOutOfBoundsException

     *           if {@code line < 1}

     *           if {@code line > no. of lines}

     */

    long getPosition(long line, long column);

    /**

     * Find the line containing a position; a line termination

     * character is on the line it terminates.

     *

     * @param   pos  character offset of the position

     * @return the line number of pos (first line is 1)

     */

    long getLineNumber(long pos);

    /**

     * Find the column for a character position.

     * Tab characters preceding the position on the same line

     * will be expanded when calculating the column number.

     *

     * @param  pos   character offset of the position

     * @return       the tab-expanded column number of pos (first column is 1)

     */

    long getColumnNumber(long pos);

}