Java Array Unpack unpack(byte[] bytes)

Description

unpack

License

Open Source License

Declaration

public static String unpack(byte[] bytes) 

Method Source Code

//package com.java2s;
//License from project: Open Source License 

public class Main {
    private static int[] KEYS = { 215, 203, 83, 158, 104, 101, 93, 84, 107,
            103, 109, 95, 94, 98, 89, 86, 70, 41, 32, 27, 24, 23, -1, -2,
            26, -3, -4, 31, 30, -5, -6, -7, 37, 38, 36, -8, -9, -10, 40,
            -11, -12, 55, 48, 46, 47, -13, -14, -15, 52, 51, -16, -17, 54,
            -18, -19, 63, 60, 59, -20, -21, 62, -22, -23, 67, 66, -24, -25,
            69, -26, -27, 199, 132, 80, 77, 76, -28, -29, 79, -30, -31, 87,
            85, -32, -33, -34, -35, -36, 197, -37, 91, -38, 134, -39, -40,
            -41, 97, -42, -43, 133, 106, -44, 117, -45, -46, 139, -47, -48,
            110, -49, -50, 114, 113, -51, -52, 116, -53, -54, 135, 138,
            136, 129, 125, 124, -55, -56, 130, 128, -57, -58, -59, 183,
            -60, -61, -62, -63, -64, 148, -65, -66, 153, 149, 145, 144,
            -67, -68, 147, -69, -70, -71, 152, 154, -72, -73, -74, 157,
            171, -75, -76, 207, 184, 174, 167, 166, 165, -77, -78, -79,
            172, 170, -80, -81, -82, 178, -83, 177, 182, -84, -85, 187,
            181, -86, -87, -88, -89, 206, 221, -90, 189, -91, 198, 254,
            262, 195, 196, -92, -93, -94, -95, -96, 252, 255, 250, -97,
            211, 209, -98, -99, 212, -100, 213, -101, -102, -103, 224,
            -104, 232, 227, 220, 226, -105, -106, 246, 236, -107, 243,
            -108, -109, 231, 237, 235, -110, -111, 239, 238, -112, -113,
            -114, -115, -116, 241, -117, 244, -118, -119, 248, -120, 249,
            -121, -122, -123, 253, -124, -125, -126, -127, 259, 258, -128,
            -129, 261, -130, -131, 390, 327, 296, 281, 274, 271, 270, -132,
            -133, 273, -134, -135, 278, 277, -136, -137, 280, -138, -139,
            289, 286, 285, -140, -141, 288, -142, -143, 293, 292, -144,
            -145, 295, -146, -147, 312, 305, 302, 301, -148, -149, 304,
            -150, -151, 309, 308, -152, -153, 311, -154, -155, 320, 317,
            316, -156, -157, 319, -158, -159, 324, 323, -160, -161, 326,
            -162, -163, 359, 344, 337, 334, 333, -164, -165, 336, -166,
            -167, 341, 340, -168, -169, 343, -170, -171, 352, 349, 348,
            -172, -173, 351, -174, -175, 356, 355, -176, -177, 358, -178,
            -179, 375, 368, 365, 364, -180, -181, 367, -182, -183, 372,
            371, -184, -185, 374, -186, -187, 383, 380, 379, -188, -189,
            382, -190, -191, 387, 386, -192, -193, 389, -194, -195, 454,
            423, 408, 401, 398, 397, -196, -197, 400, -198, -199, 405, 404,
            -200, -201, 407, -202, -203, 416, 413, 412, -204, -205, 415,
            -206, -207, 420, 419, -208, -209, 422, -210, -211, 439, 432,
            429, 428, -212, -213, 431, -214, -215, 436, 435, -216, -217,
            438, -218, -219, 447, 444, 443, -220, -221, 446, -222, -223,
            451, 450, -224, -225, 453, -226, -227, 486, 471, 464, 461, 460,
            -228, -229, 463, -230, -231, 468, 467, -232, -233, 470, -234,
            -235, 479, 476, 475, -236, -237, 478, -238, -239, 483, 482,
            -240, -241, 485, -242, -243, 499, 495, 492, 491, -244, -245,
            494, -246, -247, 497, -248, 502, -249, 506, 503, -250, -251,
            505, -252, -253, 508, -254, 510, -255, -256, 0 };

    public static String unpack(byte[] bytes) {
        if (bytes.length == 0)
            return "";

        int len = bytes[0] & 0xFF, off = 1;
        StringBuilder builder = new StringBuilder();

        int key = 0;
        for (;;) {
            byte b = bytes[off++];
            for (int mask = 0x80; mask != 0; mask >>= 1) {
                if ((b & mask) == 0)
                    key++;// w  w  w. j  a  va  2  s.co  m
                else
                    key = KEYS[key];

                int chr = KEYS[key];
                if (chr < 0) {
                    builder.append((char) ((chr & 0xFF) ^ 0xFF));
                    if (builder.length() >= len)
                        return builder.toString();

                    key = 0;
                }
            }
        }
    }
}

Related

1. unpack(byte[] array)
2. unpack(double[] packed, int width, int height, int outputIndex)
3. unpack(int[] sourcearray, int arraypos, int[] data, int datapos, int num, int b)
4. unpackBCD(byte[] source)
5. unpackDie(byte[] bytes)