1 /*

     2  * Copyright (c) 1996, 1998, 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 sun.io;

    27 

    28 /**

    29  * @author Limin Shi

    30  * @author Mark Son-Bell

    31  */

    32 

    33 public class CharToByteSJIS extends CharToByteJIS0208 {

    34     CharToByteJIS0201 cbJIS0201 = new CharToByteJIS0201();

    35 

    36     public String getCharacterEncoding() {

    37         return "SJIS";

    38     }

    39 

    40     protected int convSingleByte(char inputChar, byte[] outputByte) {

    41         byte b;

    42 

    43         // \u0000 - \u007F map straight through

    44         if ((inputChar & 0xFF80) == 0) {

    45             outputByte[0] = (byte)inputChar;

    46             return 1;

    47         }

    48 

    49         if ((b = cbJIS0201.getNative(inputChar)) == 0)

    50             return 0;

    51 

    52         outputByte[0] = b;

    53         return 1;

    54     }

    55 

    56     protected int getNative(char ch) {

    57         int offset = index1[ch >> 8] << 8;

    58         int pos = index2[offset >> 12].charAt((offset & 0xfff) + (ch & 0xff));

    59         if (pos == 0) {

    60             /* Zero value indicates this Unicode has no mapping to JIS0208.

    61              * We bail here because the JIS -> SJIS algorithm produces

    62              * bogus SJIS values for invalid JIS input.  Zero should be the

    63              * only invalid JIS value in our table.

    64              */

    65             return 0;

    66         }

    67         /*

    68          * This algorithm for converting from JIS to SJIS comes from Ken Lunde's

    69          * "Understanding Japanese Information Processing", pg 163.

    70          */

    71         int c1 = (pos >> 8) & 0xff;

    72         int c2 = pos & 0xff;

    73         int rowOffset = c1 < 0x5F ? 0x70 : 0xB0;

    74         int cellOffset = (c1 % 2 == 1) ? (c2 > 0x5F ? 0x20 : 0x1F) : 0x7E;

    75         return ((((c1 + 1 ) >> 1) + rowOffset) << 8) | (c2 + cellOffset);

    76     }

    77 }