bidiorder.java

处理PDF

        
        for (int level = highestLevel; level >= lowestOddLevel; --level) {
            for (int i = 0; i < lineLength; ++i) {
                if (levels[i] >= level) {
                    // find range of text at or above this level
                    int start = i;
                    int limit = i + 1;
                    while (limit < lineLength && levels[limit] >= level) {
                        ++limit;
                    }
                    
                    // reverse run
                    for (int j = start, k = limit - 1; j < k; ++j, --k) {
                        int temp = result[j];
                        result[j] = result[k];
                        result[k] = temp;
                    }
                    
                    // skip to end of level run
                    i = limit;
                }
            }
        }
        
        return result;
    }
    
    /**
     * Return the base level of the paragraph.
     */
    public byte getBaseLevel() {
        return paragraphEmbeddingLevel;
    }
    
    // --- internal utilities -------------------------------------------------
    
    /**
     * Return true if the type is considered a whitespace type for the line break rules.
     */
    private static boolean isWhitespace(byte biditype) {
        switch (biditype) {
            case LRE:
            case RLE:
            case LRO:
            case RLO:
            case PDF:
            case BN:
            case WS:
                return true;
            default:
                return false;
        }
    }
    
    /**
     * Return the strong type (L or R) corresponding to the level.
     */
    private static byte typeForLevel(int level) {
        return ((level & 0x1) == 0) ? L : R;
    }
    
    /**
     * Return the limit of the run starting at index that includes only resultTypes in validSet.
     * This checks the value at index, and will return index if that value is not in validSet.
     */
    private int findRunLimit(int index, int limit, byte[] validSet) {
        --index;
        loop:
            while (++index < limit) {
                byte t = resultTypes[index];
                for (int i = 0; i < validSet.length; ++i) {
                    if (t == validSet[i]) {
                        continue loop;
                    }
                }
                // didn't find a match in validSet
                return index;
            }
            return limit;
    }
    
    /**
     * Return the start of the run including index that includes only resultTypes in validSet.
     * This assumes the value at index is valid, and does not check it.
     */
    private int findRunStart(int index, byte[] validSet) {
        loop:
            while (--index >= 0) {
                byte t = resultTypes[index];
                for (int i = 0; i < validSet.length; ++i) {
                    if (t == validSet[i]) {
                        continue loop;
                    }
                }
                return index + 1;
            }
            return 0;
    }
    
    /**
     * Set resultTypes from start up to (but not including) limit to newType.
     */
    private void setTypes(int start, int limit, byte newType) {
        for (int i = start; i < limit; ++i) {
            resultTypes[i] = newType;
        }
    }
    
    /**
     * Set resultLevels from start up to (but not including) limit to newLevel.
     */
    private void setLevels(int start, int limit, byte newLevel) {
        for (int i = start; i < limit; ++i) {
            resultLevels[i] = newLevel;
        }
    }
    
    // --- input validation ---------------------------------------------------
    
    /**
     * Throw exception if type array is invalid.
     */
    private static void validateTypes(byte[] types) {
        if (types == null) {
            throw new IllegalArgumentException("types is null");
        }
        for (int i = 0; i < types.length; ++i) {
            if (types[i] < TYPE_MIN || types[i] > TYPE_MAX) {
                throw new IllegalArgumentException("illegal type value at " + i + ": " + types[i]);
            }
        }
        for (int i = 0; i < types.length - 1; ++i) {
            if (types[i] == B) {
                throw new IllegalArgumentException("B type before end of paragraph at index: " + i);
            }
        }
    }
    
    /**
     * Throw exception if paragraph embedding level is invalid. Special allowance for -1 so that
     * default processing can still be performed when using this API.
     */
    private static void validateParagraphEmbeddingLevel(byte paragraphEmbeddingLevel) {
        if (paragraphEmbeddingLevel != -1 &&
        paragraphEmbeddingLevel != 0 &&
        paragraphEmbeddingLevel != 1) {
            throw new IllegalArgumentException("illegal paragraph embedding level: " + paragraphEmbeddingLevel);
        }
    }
    
    /**
     * Throw exception if line breaks array is invalid.
     */
    private static void validateLineBreaks(int[] linebreaks, int textLength) {
        int prev = 0;
        for (int i = 0; i < linebreaks.length; ++i) {
            int next = linebreaks[i];
            if (next <= prev) {
                throw new IllegalArgumentException("bad linebreak: " + next + " at index: " + i);
            }
            prev = next;
        }
        if (prev != textLength) {
            throw new IllegalArgumentException("last linebreak must be at " + textLength);
        }
    }
    
    private static final byte rtypes[] = new byte[0x10000];
    
    private static char baseTypes[] = {
        0, 8, (char)BN, 9, 9, (char)S, 10, 10, (char)B, 11, 11, (char)S, 12, 12, (char)WS, 13, 13, (char)B,
        14, 27, (char)BN, 28, 30, (char)B, 31, 31, (char)S, 32, 32, (char)WS, 33, 34, (char)ON, 35, 37, (char)ET,
        38, 42, (char)ON, 43, 43, (char)ET, 44, 44, (char)CS, 45, 45, (char)ET, 46, 46, (char)CS, 47, 47, (char)ES,
        48, 57, (char)EN, 58, 58, (char)CS, 59, 64, (char)ON, 65, 90, (char)L, 91, 96, (char)ON, 97, 122, (char)L,
        123, 126, (char)ON, 127, 132, (char)BN, 133, 133, (char)B, 134, 159, (char)BN, 160, 160, (char)CS,
        161, 161, (char)ON, 162, 165, (char)ET, 166, 169, (char)ON, 170, 170, (char)L, 171, 175, (char)ON,
        176, 177, (char)ET, 178, 179, (char)EN, 180, 180, (char)ON, 181, 181, (char)L, 182, 184, (char)ON,
        185, 185, (char)EN, 186, 186, (char)L, 187, 191, (char)ON, 192, 214, (char)L, 215, 215, (char)ON,
        216, 246, (char)L, 247, 247, (char)ON, 248, 696, (char)L, 697, 698, (char)ON, 699, 705, (char)L,
        706, 719, (char)ON, 720, 721, (char)L, 722, 735, (char)ON, 736, 740, (char)L, 741, 749, (char)ON,
        750, 750, (char)L, 751, 767, (char)ON, 768, 855, (char)NSM, 856, 860, (char)L, 861, 879, (char)NSM,
        880, 883, (char)L, 884, 885, (char)ON, 886, 893, (char)L, 894, 894, (char)ON, 895, 899, (char)L,
        900, 901, (char)ON, 902, 902, (char)L, 903, 903, (char)ON, 904, 1013, (char)L, 1014, 1014, (char)ON,
        1015, 1154, (char)L, 1155, 1158, (char)NSM, 1159, 1159, (char)L, 1160, 1161, (char)NSM,
        1162, 1417, (char)L, 1418, 1418, (char)ON, 1419, 1424, (char)L, 1425, 1441, (char)NSM,
        1442, 1442, (char)L, 1443, 1465, (char)NSM, 1466, 1466, (char)L, 1467, 1469, (char)NSM,
        1470, 1470, (char)R, 1471, 1471, (char)NSM, 1472, 1472, (char)R, 1473, 1474, (char)NSM,
        1475, 1475, (char)R, 1476, 1476, (char)NSM, 1477, 1487, (char)L, 1488, 1514, (char)R,
        1515, 1519, (char)L, 1520, 1524, (char)R, 1525, 1535, (char)L, 1536, 1539, (char)AL,
        1540, 1547, (char)L, 1548, 1548, (char)CS, 1549, 1549, (char)AL, 1550, 1551, (char)ON,
        1552, 1557, (char)NSM, 1558, 1562, (char)L, 1563, 1563, (char)AL, 1564, 1566, (char)L,
        1567, 1567, (char)AL, 1568, 1568, (char)L, 1569, 1594, (char)AL, 1595, 1599, (char)L,
        1600, 1610, (char)AL, 1611, 1624, (char)NSM, 1625, 1631, (char)L, 1632, 1641, (char)AN,
        1642, 1642, (char)ET, 1643, 1644, (char)AN, 1645, 1647, (char)AL, 1648, 1648, (char)NSM,
        1649, 1749, (char)AL, 1750, 1756, (char)NSM, 1757, 1757, (char)AL, 1758, 1764, (char)NSM,
        1765, 1766, (char)AL, 1767, 1768, (char)NSM, 1769, 1769, (char)ON, 1770, 1773, (char)NSM,
        1774, 1775, (char)AL, 1776, 1785, (char)EN, 1786, 1805, (char)AL, 1806, 1806, (char)L,
        1807, 1807, (char)BN, 1808, 1808, (char)AL, 1809, 1809, (char)NSM, 1810, 1839, (char)AL,
        1840, 1866, (char)NSM, 1867, 1868, (char)L, 1869, 1871, (char)AL, 1872, 1919, (char)L,
        1920, 1957, (char)AL, 1958, 1968, (char)NSM, 1969, 1969, (char)AL, 1970, 2304, (char)L,
        2305, 2306, (char)NSM, 2307, 2363, (char)L, 2364, 2364, (char)NSM, 2365, 2368, (char)L,
        2369, 2376, (char)NSM, 2377, 2380, (char)L, 2381, 2381, (char)NSM, 2382, 2384, (char)L,
        2385, 2388, (char)NSM, 2389, 2401, (char)L, 2402, 2403, (char)NSM, 2404, 2432, (char)L,
        2433, 2433, (char)NSM, 2434, 2491, (char)L, 2492, 2492, (char)NSM, 2493, 2496, (char)L,
        2497, 2500, (char)NSM, 2501, 2508, (char)L, 2509, 2509, (char)NSM, 2510, 2529, (char)L,
        2530, 2531, (char)NSM, 2532, 2545, (char)L, 2546, 2547, (char)ET, 2548, 2560, (char)L,
        2561, 2562, (char)NSM, 2563, 2619, (char)L, 2620, 2620, (char)NSM, 2621, 2624, (char)L,
        2625, 2626, (char)NSM, 2627, 2630, (char)L, 2631, 2632, (char)NSM, 2633, 2634, (char)L,
        2635, 2637, (char)NSM, 2638, 2671, (char)L, 2672, 2673, (char)NSM, 2674, 2688, (char)L,
        2689, 2690, (char)NSM, 2691, 2747, (char)L, 2748, 2748, (char)NSM, 2749, 2752, (char)L,
        2753, 2757, (char)NSM, 2758, 2758, (char)L, 2759, 2760, (char)NSM, 2761, 2764, (char)L,
        2765, 2765, (char)NSM, 2766, 2785, (char)L, 2786, 2787, (char)NSM, 2788, 2800, (char)L,
        2801, 2801, (char)ET, 2802, 2816, (char)L, 2817, 2817, (char)NSM, 2818, 2875, (char)L,
        2876, 2876, (char)NSM, 2877, 2878, (char)L, 2879, 2879, (char)NSM, 2880, 2880, (char)L,
        2881, 2883, (char)NSM, 2884, 2892, (char)L, 2893, 2893, (char)NSM, 2894, 2901, (char)L,
        2902, 2902, (char)NSM, 2903, 2945, (char)L, 2946, 2946, (char)NSM, 2947, 3007, (char)L,
        3008, 3008, (char)NSM, 3009, 3020, (char)L, 3021, 3021, (char)NSM, 3022, 3058, (char)L,
        3059, 3064, (char)ON, 3065, 3065, (char)ET, 3066, 3066, (char)ON, 3067, 3133, (char)L,
        3134, 3136, (char)NSM, 3137, 3141, (char)L, 3142, 3144, (char)NSM, 3145, 3145, (char)L,
        3146, 3149, (char)NSM, 3150, 3156, (char)L, 3157, 3158, (char)NSM, 3159, 3259, (char)L,
        3260, 3260, (char)NSM, 3261, 3275, (char)L, 3276, 3277, (char)NSM, 3278, 3392, (char)L,
        3393, 3395, (char)NSM, 3396, 3404, (char)L, 3405, 3405, (char)NSM, 3406, 3529, (char)L,
        3530, 3530, (char)NSM, 3531, 3537, (char)L, 3538, 3540, (char)NSM, 3541, 3541, (char)L,
        3542, 3542, (char)NSM, 3543, 3632, (char)L, 3633, 3633, (char)NSM, 3634, 3635, (char)L,
        3636, 3642, (char)NSM, 3643, 3646, (char)L, 3647, 3647, (char)ET, 3648, 3654, (char)L,
        3655, 3662, (char)NSM, 3663, 3760, (char)L, 3761, 3761, (char)NSM, 3762, 3763, (char)L,
        3764, 3769, (char)NSM, 3770, 3770, (char)L, 3771, 3772, (char)NSM, 3773, 3783, (char)L,
        3784, 3789, (char)NSM, 3790, 3863, (char)L, 3864, 3865, (char)NSM, 3866, 3892, (char)L,
        3893, 3893, (char)NSM, 3894, 3894, (char)L, 3895, 3895, (char)NSM, 3896, 3896, (char)L,
        3897, 3897, (char)NSM, 3898, 3901, (char)ON, 3902, 3952, (char)L, 3953, 3966, (char)NSM,
        3967, 3967, (char)L, 3968, 3972, (char)NSM, 3973, 3973, (char)L, 3974, 3975, (char)NSM,
        3976, 3983, (char)L, 3984, 3991, (char)NSM, 3992, 3992, (char)L, 3993, 4028, (char)NSM,
        4029, 4037, (char)L, 4038, 4038, (char)NSM, 4039, 4140, (char)L, 4141, 4144, (char)NSM,
        4145, 4145, (char)L, 4146, 4146, (char)NSM, 4147, 4149, (char)L, 4150, 4151, (char)NSM,
        4152, 4152, (char)L, 4153, 4153, (char)NSM, 4154, 4183, (char)L, 4184, 4185, (char)NSM,
        4186, 5759, (char)L, 5760, 5760, (char)WS, 5761, 5786, (char)L, 5787, 5788, (char)ON,
        5789, 5905, (char)L, 5906, 5908, (char)NSM, 5909, 5937, (char)L, 5938, 5940, (char)NSM,
        5941, 5969, (char)L, 5970, 5971, (char)NSM, 5972, 6001, (char)L, 6002, 6003, (char)NSM,
        6004, 6070, (char)L, 6071, 6077, (char)NSM, 6078, 6085, (char)L, 6086, 6086, (char)NSM,
        6087, 6088, (char)L, 6089, 6099, (char)NSM, 6100, 6106, (char)L, 6107, 6107, (char)ET,
        6108, 6108, (char)L, 6109, 6109, (char)NSM, 6110, 6127, (char)L, 6128, 6137, (char)ON,
        6138, 6143, (char)L, 6144, 6154, (char)ON, 6155, 6157, (char)NSM, 6158, 6158, (char)WS,
        6159, 6312, (char)L, 6313, 6313, (char)NSM, 6314, 6431, (char)L, 6432, 6434, (char)NSM,
        6435, 6438, (char)L, 6439, 6443, (char)NSM, 6444, 6449, (char)L, 6450, 6450, (char)NSM,
        6451, 6456, (char)L, 6457, 6459, (char)NSM, 6460, 6463, (char)L, 6464, 6464, (char)ON,
        6465, 6467, (char)L, 6468, 6469, (char)ON, 6470, 6623, (char)L, 6624, 6655, (char)ON,
        6656, 8124, (char)L, 8125, 8125, (char)ON, 8126, 8126, (char)L, 8127, 8129, (char)ON,
        8130, 8140, (char)L, 8141, 8143, (char)ON, 8144, 8156, (char)L, 8157, 8159, (char)ON,
        8160, 8172, (char)L, 8173, 8175, (char)ON, 8176, 8188, (char)L, 8189, 8190, (char)ON,
        8191, 8191, (char)L, 8192, 8202, (char)WS, 8203, 8205, (char)BN, 8206, 8206, (char)L,
        8207, 8207, (char)R, 8208, 8231, (char)ON, 8232, 8232, (char)WS, 8233, 8233, (char)B,
        8234, 8234, (char)LRE, 8235, 8235, (char)RLE, 8236, 8236, (char)PDF, 8237, 8237, (char)LRO,
        8238, 8238, (char)RLO, 8239, 8239, (char)WS, 8240, 8244, (char)ET, 8245, 8276, (char)ON,
        8277, 8278, (char)L, 8279, 8279, (char)ON, 8280, 8286, (char)L, 8287, 8287, (char)WS,
        8288, 8291, (char)BN, 8292, 8297, (char)L, 8298, 8303, (char)BN, 8304, 8304, (char)EN,
        8305, 8307, (char)L, 8308, 8313, (char)EN, 8314, 8315, (char)ET, 8316, 8318, (char)ON,
        8319, 8319, (char)L, 8320, 8329, (char)EN, 8330, 8331, (char)ET, 8332, 8334, (char)ON,
        8335, 8351, (char)L, 8352, 8369, (char)ET, 8370, 8399, (char)L, 8400, 8426, (char)NSM,
        8427, 8447, (char)L, 8448, 8449, (char)ON, 8450, 8450, (char)L, 8451, 8454, (char)ON,
        8455, 8455, (char)L, 8456, 8457, (char)ON, 8458, 8467, (char)L, 8468, 8468, (char)ON,
        8469, 8469, (char)L, 8470, 8472, (char)ON, 8473, 8477, (char)L, 8478, 8483, (char)ON,
        8484, 8484, (char)L, 8485, 8485, (char)ON, 8486, 8486, (char)L, 8487, 8487, (char)ON,
        8488, 8488, (char)L, 8489, 8489, (char)ON, 8490, 8493, (char)L, 8494, 8494, (char)ET,
        8495, 8497, (char)L, 8498, 8498, (char)ON, 8499, 8505, (char)L, 8506, 8507, (char)ON,
        8508, 8511, (char)L, 8512, 8516, (char)ON, 8517, 8521, (char)L, 8522, 8523, (char)ON,
        8524, 8530, (char)L, 8531, 8543, (char)ON, 8544, 8591, (char)L, 8592, 8721, (char)ON,
        8722, 8723, (char)ET, 8724, 9013, (char)ON, 9014, 9082, (char)L, 9083, 9108, (char)ON,
        9109, 9109, (char)L, 9110, 9168, (char)ON, 9169, 9215, (char)L, 9216, 9254, (char)ON,
        9255, 9279, (char)L, 9280, 9290, (char)ON, 9291, 9311, (char)L, 9312, 9371, (char)EN,
        9372, 9449, (char)L, 9450, 9450, (char)EN, 9451, 9751, (char)ON, 9752, 9752, (char)L,
        9753, 9853, (char)ON, 9854, 9855, (char)L, 9856, 9873, (char)ON, 9874, 9887, (char)L,
        9888, 9889, (char)ON, 9890, 9984, (char)L, 9985, 9988, (char)ON, 9989, 9989, (char)L,
        9990, 9993, (char)ON, 9994, 9995, (char)L, 9996, 10023, (char)ON, 10024, 10024, (char)L,
        10025, 10059, (char)ON, 10060, 10060, (char)L, 10061, 10061, (char)ON, 10062, 10062, (char)L,
        10063, 10066, (char)ON, 10067, 10069, (char)L, 10070, 10070, (char)ON, 10071, 10071, (char)L,
        10072, 10078, (char)ON, 10079, 10080, (char)L, 10081, 10132, (char)ON, 10133, 10135, (char)L,
        10136, 10159, (char)ON, 10160, 10160, (char)L, 10161, 10174, (char)ON, 10175, 10191, (char)L,
        10192, 10219, (char)ON, 10220, 10223, (char)L, 10224, 11021, (char)ON, 11022, 11903, (char)L,
        11904, 11929, (char)ON, 11930, 11930, (char)L, 11931, 12019, (char)ON, 12020, 12031, (char)L,
        12032, 12245, (char)ON, 12246, 12271, (char)L, 12272, 12283, (char)ON, 12284, 12287, (char)L,
        12288, 12288, (char)WS, 12289, 12292, (char)ON, 12293, 12295, (char)L, 12296, 12320, (char)ON,
        12321, 12329, (char)L, 12330, 12335, (char)NSM, 12336, 12336, (char)ON, 12337, 12341, (char)L,
        12342, 12343, (char)ON, 12344, 12348, (char)L, 12349, 12351, (char)ON, 12352, 12440, (char)L,
        12441, 12442, (char)NSM, 12443, 12444, (char)ON, 12445, 12447, (char)L, 12448, 12448, (char)ON,
        12449, 12538, (char)L, 12539, 12539, (char)ON, 12540, 12828, (char)L, 12829, 12830, (char)ON,
        12831, 12879, (char)L, 12880, 12895, (char)ON, 12896, 12923, (char)L, 12924, 12925, (char)ON,
        12926, 12976, (char)L, 12977, 12991, (char)ON, 12992, 13003, (char)L, 13004, 13007, (char)ON,
        13008, 13174, (char)L, 13175, 13178, (char)ON, 13179, 13277, (char)L, 13278, 13279, (char)ON,
        13280, 13310, (char)L, 13311, 13311, (char)ON, 13312, 19903, (char)L, 19904, 19967, (char)ON,
        19968, 42127, (char)L, 42128, 42182, (char)ON, 42183, 64284, (char)L, 64285, 64285, (char)R,
        64286, 64286, (char)NSM, 64287, 64296, (char)R, 64297, 64297, (char)ET, 64298, 64310, (char)R,
        64311, 64311, (char)L, 64312, 64316, (char)R, 64317, 64317, (char)L, 64318, 64318, (char)R,
        64319, 64319, (char)L, 64320, 64321, (char)R, 64322, 64322, (char)L, 64323, 64324, (char)R,
        64325, 64325, (char)L, 64326, 64335, (char)R, 64336, 64433, (char)AL, 64434, 64466, (char)L,
        64467, 64829, (char)AL, 64830, 64831, (char)ON, 64832, 64847, (char)L, 64848, 64911, (char)AL,
        64912, 64913, (char)L, 64914, 64967, (char)AL, 64968, 65007, (char)L, 65008, 65020, (char)AL,
        65021, 65021, (char)ON, 65022, 65023, (char)L, 65024, 65039, (char)NSM, 65040, 65055, (char)L,
        65056, 65059, (char)NSM, 65060, 65071, (char)L, 65072, 65103, (char)ON, 65104, 65104, (char)CS,
        65105, 65105, (char)ON, 65106, 65106, (char)CS, 65107, 65107, (char)L, 65108, 65108, (char)ON,
        65109, 65109, (char)CS, 65110, 65118, (char)ON, 65119, 65119, (char)ET, 65120, 65121, (char)ON,
        65122, 65123, (char)ET, 65124, 65126, (char)ON, 65127, 65127, (char)L, 65128, 65128, (char)ON,
        65129, 65130, (char)ET, 65131, 65131, (char)ON, 65132, 65135, (char)L, 65136, 65140, (char)AL,
        65141, 65141, (char)L, 65142, 65276, (char)AL, 65277, 65278, (char)L, 65279, 65279, (char)BN,
        65280, 65280, (char)L, 65281, 65282, (char)ON, 65283, 65285, (char)ET, 65286, 65290, (char)ON,
        65291, 65291, (char)ET, 65292, 65292, (char)CS, 65293, 65293, (char)ET, 65294, 65294, (char)CS,
        65295, 65295, (char)ES, 65296, 65305, (char)EN, 65306, 65306, (char)CS, 65307, 65312, (char)ON,
        65313, 65338, (char)L, 65339, 65344, (char)ON, 65345, 65370, (char)L, 65371, 65381, (char)ON,
        65382, 65503, (char)L, 65504, 65505, (char)ET, 65506, 65508, (char)ON, 65509, 65510, (char)ET,
        65511, 65511, (char)L, 65512, 65518, (char)ON, 65519, 65528, (char)L, 65529, 65531, (char)BN,
        65532, 65533, (char)ON, 65534, 65535, (char)L};
        
    static {
        for (int k = 0; k < baseTypes.length; ++k) {
            int start = baseTypes[k];
            int end = baseTypes[++k];
            byte b = (byte)baseTypes[++k];
            while (start <= end)
                rtypes[start++] = b;
        }
    }        
}