1 /*

     2  * Copyright (c) 2001, 2011, 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.reflect;

    27 

    28 /** It is necessary to use a "bootstrap" UTF-8 encoder for encoding

    29     constant pool entries because the character set converters rely on

    30     Class.newInstance(). */

    31 

    32 class UTF8 {

    33     // This encoder is not quite correct.  It does not handle surrogate pairs.

    34     static byte[] encode(String str) {

    35         int len = str.length();

    36         byte[] res = new byte[utf8Length(str)];

    37         int utf8Idx = 0;

    38         try {

    39             for (int i = 0; i < len; i++) {

    40                 int c = str.charAt(i) & 0xFFFF;

    41                 if (c >= 0x0001 && c <= 0x007F) {

    42                     res[utf8Idx++] = (byte) c;

    43                 } else if (c == 0x0000 ||

    44                            (c >= 0x0080 && c <= 0x07FF)) {

    45                     res[utf8Idx++] = (byte) (0xC0 + (c >> 6));

    46                     res[utf8Idx++] = (byte) (0x80 + (c & 0x3F));

    47                 } else {

    48                     res[utf8Idx++] = (byte) (0xE0 + (c >> 12));

    49                     res[utf8Idx++] = (byte) (0x80 + ((c >> 6) & 0x3F));

    50                     res[utf8Idx++] = (byte) (0x80 + (c & 0x3F));

    51                 }

    52             }

    53         } catch (ArrayIndexOutOfBoundsException e) {

    54             throw new InternalError

    55                 ("Bug in sun.reflect bootstrap UTF-8 encoder", e);

    56         }

    57         return res;

    58     }

    59 

    60     private static int utf8Length(String str) {

    61         int len = str.length();

    62         int utf8Len = 0;

    63         for (int i = 0; i < len; i++) {

    64             int c = str.charAt(i) & 0xFFFF;

    65             if (c >= 0x0001 && c <= 0x007F) {

    66                 utf8Len += 1;

    67             } else if (c == 0x0000 ||

    68                        (c >= 0x0080 && c <= 0x07FF)) {

    69                 utf8Len += 2;

    70             } else {

    71                 utf8Len += 3;

    72             }

    73         }

    74         return utf8Len;

    75     }

    76 }