base64 编码 换行问题

 

 

public final class Base64 {
    private static final byte[] DECODE_TABLE = new byte[] { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 62, 0, 0, 0, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 0,
            0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 0, 0, 0, 0, 0, 0, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 0,
            0, 0, 0, 0 };

    // "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/ "
    private static final byte[] ENCODE_TABLE = new byte[] { 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113,
            114, 115, 116, 117, 118, 119, 120, 121, 122, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 43, 47 };

    static {
        // create encode table
        // ENCODE_TABLE = new byte[64];
        int index = 0;
        for (char c = 'A'; c <= 'Z'; c++)
            ENCODE_TABLE[index++] = (byte) c;
        for (char c = 'a'; c <= 'z'; c++)
            ENCODE_TABLE[index++] = (byte) c;
        for (char c = '0'; c <= '9'; c++)
            ENCODE_TABLE[index++] = (byte) c;
        ENCODE_TABLE[index++] = (byte) '+';
        ENCODE_TABLE[index++] = (byte) '/';

        // create decode table
        for (int i = 0; i < 64; i++)
            DECODE_TABLE[(int) ENCODE_TABLE[i]] = (byte) i;
    }

    private Base64() {
    }

    public static byte[] encode(byte[] data) {
        if (data == null)
            return null;

        int fullGroups = data.length / 3;
        int resultBytes = fullGroups * 4;
        if (data.length % 3 != 0)
            resultBytes += 4;

        byte[] result = new byte[resultBytes];
        int resultIndex = 0;
        int dataIndex = 0;
        int temp = 0;
        for (int i = 0; i < fullGroups; i++) {
            temp = (data[dataIndex++] & 0xff) << 16 | (data[dataIndex++] & 0xff) << 8 | data[dataIndex++] & 0xff;

            result[resultIndex++] = ENCODE_TABLE[(temp >> 18) & 0x3f];
            result[resultIndex++] = ENCODE_TABLE[(temp >> 12) & 0x3f];
            result[resultIndex++] = ENCODE_TABLE[(temp >> 6) & 0x3f];
            result[resultIndex++] = ENCODE_TABLE[temp & 0x3f];
        }
        temp = 0;
        while (dataIndex < data.length) {
            temp <<= 8;
            temp |= data[dataIndex++] & 0xff;
        }
        switch (data.length % 3) {
        case 1:
            temp <<= 8;
            temp <<= 8;
            result[resultIndex++] = ENCODE_TABLE[(temp >> 18) & 0x3f];
            result[resultIndex++] = ENCODE_TABLE[(temp >> 12) & 0x3f];
            result[resultIndex++] = 0x3D;
            result[resultIndex++] = 0x3D;
            break;
        case 2:
            temp <<= 8;
            result[resultIndex++] = ENCODE_TABLE[(temp >> 18) & 0x3f];
            result[resultIndex++] = ENCODE_TABLE[(temp >> 12) & 0x3f];
            result[resultIndex++] = ENCODE_TABLE[(temp >> 6) & 0x3f];
            result[resultIndex++] = 0x3D;
            break;
        default:
            break;
        }

        return result;
    }

    public static byte[] decode(byte[] base64Data) {
        if (base64Data == null)
            return null;
        if (base64Data.length == 0)
            return new byte[0];
        if (base64Data.length % 4 != 0)
            throw new IllegalArgumentException("数据不完整，长度为： " + base64Data.length);

        byte[] result = null;
        int groupCount = base64Data.length / 4;

        int lastData = base64Data.length;
        while (base64Data[lastData - 1] == 0x3D) {
            if (--lastData == 0)
                return new byte[0];
        }
        result = new byte[lastData - groupCount];

        int temp = 0;
        int resultIndex = 0;
        int dataIndex = 0;
        for (; dataIndex + 4 < base64Data.length;) {
            temp = DECODE_TABLE[base64Data[dataIndex++]];
            temp = (temp << 6) + DECODE_TABLE[base64Data[dataIndex++]];
            temp = (temp << 6) + DECODE_TABLE[base64Data[dataIndex++]];
            temp = (temp << 6) + DECODE_TABLE[base64Data[dataIndex++]];

            result[resultIndex++] = (byte) ((temp >> 16) & 0xff);
            result[resultIndex++] = (byte) ((temp >> 8) & 0xff);
            result[resultIndex++] = (byte) (temp & 0xff);
        }

        temp = 0;
        int j = 0;
        for (; dataIndex < base64Data.length; dataIndex++, j++)
            temp = (temp << 6) + DECODE_TABLE[base64Data[dataIndex]];
        for (; j < 4; j++)
            temp <<= 6;

        result[resultIndex++] = (byte) ((temp >> 16) & 0xff);
        if (base64Data[dataIndex - 2] != '=')
            result[resultIndex++] = (byte) ((temp >> 8) & 0xff);
        if (base64Data[dataIndex - 1] != '=')
            result[resultIndex++] = (byte) (temp & 0xff);

        return result;
    }

    public static void main(String[] args) {
        Base64 base64 = new Base64();
       byte [] s= base64.encode("http://212.201.208.22:2212/entry?C=0300000001&ContentID=000001000000045903&F=72103_72104".getBytes());
        System.out.println(new String(s));
        s=base64.decode(s);
        System.out.println(new String(s));
    }
}