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
26package jdk.internal.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
32class 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}
77