/*
 * Copyright 1999-2000 Sun Microsystems, Inc.  All Rights Reserved.
 * 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
 * published by the Free Software Foundation.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun in the LICENSE file that accompanied this code.
 *
 * 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.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */

package java.util.regex;


/**
 * Utility class that implements the standard C ctype functionality.
 *
 * @author Hong Zhang
 */

final class ASCII {

    static final int UPPER   = 0x00000100;

    static final int LOWER   = 0x00000200;

    static final int DIGIT   = 0x00000400;

    static final int SPACE   = 0x00000800;

    static final int PUNCT   = 0x00001000;

    static final int CNTRL   = 0x00002000;

    static final int BLANK   = 0x00004000;

    static final int HEX     = 0x00008000;

    static final int UNDER   = 0x00010000;

    static final int ASCII   = 0x0000FF00;

    static final int ALPHA   = (UPPER|LOWER);

    static final int ALNUM   = (UPPER|LOWER|DIGIT);

    static final int GRAPH   = (PUNCT|UPPER|LOWER|DIGIT);

    static final int WORD    = (UPPER|LOWER|UNDER|DIGIT);

    static final int XDIGIT  = (HEX);

    private static final int[] ctype = new int[] {
        CNTRL,                  /* 00 (NUL) */
        CNTRL,                  /* 01 (SOH) */
        CNTRL,                  /* 02 (STX) */
        CNTRL,                  /* 03 (ETX) */
        CNTRL,                  /* 04 (EOT) */
        CNTRL,                  /* 05 (ENQ) */
        CNTRL,                  /* 06 (ACK) */
        CNTRL,                  /* 07 (BEL) */
        CNTRL,                  /* 08 (BS)  */
        SPACE+CNTRL+BLANK,      /* 09 (HT)  */
        SPACE+CNTRL,            /* 0A (LF)  */
        SPACE+CNTRL,            /* 0B (VT)  */
        SPACE+CNTRL,            /* 0C (FF)  */
        SPACE+CNTRL,            /* 0D (CR)  */
        CNTRL,                  /* 0E (SI)  */
        CNTRL,                  /* 0F (SO)  */
        CNTRL,                  /* 10 (DLE) */
        CNTRL,                  /* 11 (DC1) */
        CNTRL,                  /* 12 (DC2) */
        CNTRL,                  /* 13 (DC3) */
        CNTRL,                  /* 14 (DC4) */
        CNTRL,                  /* 15 (NAK) */
        CNTRL,                  /* 16 (SYN) */
        CNTRL,                  /* 17 (ETB) */
        CNTRL,                  /* 18 (CAN) */
        CNTRL,                  /* 19 (EM)  */
        CNTRL,                  /* 1A (SUB) */
        CNTRL,                  /* 1B (ESC) */
        CNTRL,                  /* 1C (FS)  */
        CNTRL,                  /* 1D (GS)  */
        CNTRL,                  /* 1E (RS)  */
        CNTRL,                  /* 1F (US)  */
        SPACE+BLANK,            /* 20 SPACE */
        PUNCT,                  /* 21 !     */
        PUNCT,                  /* 22 "     */
        PUNCT,                  /* 23 #     */
        PUNCT,                  /* 24 $     */
        PUNCT,                  /* 25 %     */
        PUNCT,                  /* 26 &     */
        PUNCT,                  /* 27 '     */
        PUNCT,                  /* 28 (     */
        PUNCT,                  /* 29 )     */
        PUNCT,                  /* 2A *     */
        PUNCT,                  /* 2B +     */
        PUNCT,                  /* 2C ,     */
        PUNCT,                  /* 2D -     */
        PUNCT,                  /* 2E .     */
        PUNCT,                  /* 2F /     */
        DIGIT+HEX+0,            /* 30 0     */
        DIGIT+HEX+1,            /* 31 1     */
        DIGIT+HEX+2,            /* 32 2     */
        DIGIT+HEX+3,            /* 33 3     */
        DIGIT+HEX+4,            /* 34 4     */
        DIGIT+HEX+5,            /* 35 5     */
        DIGIT+HEX+6,            /* 36 6     */
        DIGIT+HEX+7,            /* 37 7     */
        DIGIT+HEX+8,            /* 38 8     */
        DIGIT+HEX+9,            /* 39 9     */
        PUNCT,                  /* 3A :     */
        PUNCT,                  /* 3B ;     */
        PUNCT,                  /* 3C <     */
        PUNCT,                  /* 3D =     */
        PUNCT,                  /* 3E >     */
        PUNCT,                  /* 3F ?     */
        PUNCT,                  /* 40 @     */
        UPPER+HEX+10,           /* 41 A     */
        UPPER+HEX+11,           /* 42 B     */
        UPPER+HEX+12,           /* 43 C     */
        UPPER+HEX+13,           /* 44 D     */
        UPPER+HEX+14,           /* 45 E     */
        UPPER+HEX+15,           /* 46 F     */
        UPPER+16,               /* 47 G     */
        UPPER+17,               /* 48 H     */
        UPPER+18,               /* 49 I     */
        UPPER+19,               /* 4A J     */
        UPPER+20,               /* 4B K     */
        UPPER+21,               /* 4C L     */
        UPPER+22,               /* 4D M     */
        UPPER+23,               /* 4E N     */
        UPPER+24,               /* 4F O     */
        UPPER+25,               /* 50 P     */
        UPPER+26,               /* 51 Q     */
        UPPER+27,               /* 52 R     */
        UPPER+28,               /* 53 S     */
        UPPER+29,               /* 54 T     */
        UPPER+30,               /* 55 U     */
        UPPER+31,               /* 56 V     */
        UPPER+32,               /* 57 W     */
        UPPER+33,               /* 58 X     */
        UPPER+34,               /* 59 Y     */
        UPPER+35,               /* 5A Z     */
        PUNCT,                  /* 5B [     */
        PUNCT,                  /* 5C \     */
        PUNCT,                  /* 5D ]     */
        PUNCT,                  /* 5E ^     */
        PUNCT|UNDER,            /* 5F _     */
        PUNCT,                  /* 60 `     */
        LOWER+HEX+10,           /* 61 a     */
        LOWER+HEX+11,           /* 62 b     */
        LOWER+HEX+12,           /* 63 c     */
        LOWER+HEX+13,           /* 64 d     */
        LOWER+HEX+14,           /* 65 e     */
        LOWER+HEX+15,           /* 66 f     */
        LOWER+16,               /* 67 g     */
        LOWER+17,               /* 68 h     */
        LOWER+18,               /* 69 i     */
        LOWER+19,               /* 6A j     */
        LOWER+20,               /* 6B k     */
        LOWER+21,               /* 6C l     */
        LOWER+22,               /* 6D m     */
        LOWER+23,               /* 6E n     */
        LOWER+24,               /* 6F o     */
        LOWER+25,               /* 70 p     */
        LOWER+26,               /* 71 q     */
        LOWER+27,               /* 72 r     */
        LOWER+28,               /* 73 s     */
        LOWER+29,               /* 74 t     */
        LOWER+30,               /* 75 u     */
        LOWER+31,               /* 76 v     */
        LOWER+32,               /* 77 w     */
        LOWER+33,               /* 78 x     */
        LOWER+34,               /* 79 y     */
        LOWER+35,               /* 7A z     */
        PUNCT,                  /* 7B {     */
        PUNCT,                  /* 7C |     */
        PUNCT,                  /* 7D }     */
        PUNCT,                  /* 7E ~     */
        CNTRL,                  /* 7F (DEL) */
    };

    static int getType(int ch) {
        return ((ch & 0xFFFFFF80) == 0 ? ctype[ch] : 0);
    }

    static boolean isType(int ch, int type) {
        return (getType(ch) & type) != 0;
    }

    static boolean isAscii(int ch) {
        return ((ch & 0xFFFFFF80) == 0);
    }

    static boolean isAlpha(int ch) {
        return isType(ch, ALPHA);
    }

    static boolean isDigit(int ch) {
        return ((ch-'0')|('9'-ch)) >= 0;
    }

    static boolean isAlnum(int ch) {
        return isType(ch, ALNUM);
    }

    static boolean isGraph(int ch) {
        return isType(ch, GRAPH);
    }

    static boolean isPrint(int ch) {
        return ((ch-0x20)|(0x7E-ch)) >= 0;
    }

    static boolean isPunct(int ch) {
        return isType(ch, PUNCT);
    }

    static boolean isSpace(int ch) {
        return isType(ch, SPACE);
    }

    static boolean isHexDigit(int ch) {
        return isType(ch, HEX);
    }

    static boolean isOctDigit(int ch) {
        return ((ch-'0')|('7'-ch)) >= 0;
    }

    static boolean isCntrl(int ch) {
        return isType(ch, CNTRL);
    }

    static boolean isLower(int ch) {
        return ((ch-'a')|('z'-ch)) >= 0;
    }

    static boolean isUpper(int ch) {
        return ((ch-'A')|('Z'-ch)) >= 0;
    }

    static boolean isWord(int ch) {
        return isType(ch, WORD);
    }

    static int toDigit(int ch) {
        return (ctype[ch & 0x7F] & 0x3F);
    }

    static int toLower(int ch) {
        return isUpper(ch) ? (ch + 0x20) : ch;
    }

    static int toUpper(int ch) {
        return isLower(ch) ? (ch - 0x20) : ch;
    }

}