世上最全最好用的数据转换工具工具类

世上最全最好用的数据转换工具工具类


import java.math.BigInteger;
import java.nio.charset.Charset;

public class FormatByteUtil {

    public static final String GBK = "GBK";
    public static final String UTF8 = "utf-8";
    public static final char[] ascii = "0123456789ABCDEF".toCharArray();
    private static char[] HEX_VOCABLE = {'0', '1', '2', '3', '4', '5', '6',
            '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};

    /**
     * 将short整型数值转换为字节数组(10进制)
     *
     * @param data
     * @return
     */
    public static byte[] getBytes(short data) {
        byte[] bytes = new byte[2];
        bytes[0] = (byte) ((data & 0xff00) >> 8);
        bytes[1] = (byte) (data & 0xff);
        return bytes;
    }

    /**
     * 将字符转换为字节数组(10进制)
     *
     * @param data
     * @return
     */
    public static byte[] getBytes(char data) {
        byte[] bytes = new byte[2];
        bytes[0] = (byte) (data >> 8);
        bytes[1] = (byte) (data);
        return bytes;
    }

    /**
     * 将布尔值转换为字节数组(10进制)
     *
     * @param data
     * @return
     */
    public static byte[] getBytes(boolean data) {
        byte[] bytes = new byte[1];
        bytes[0] = (byte) (data ? 1 : 0);
        return bytes;
    }

    /**
     * 将整型数值转换为字节数组(10进制)
     *
     * @param data
     * @return
     */
    public static byte[] getBytes(int data) {
        byte[] bytes = new byte[4];
        bytes[0] = (byte) ((data & 0xff000000) >> 24);
        bytes[1] = (byte) ((data & 0xff0000) >> 16);
        bytes[2] = (byte) ((data & 0xff00) >> 8);
        bytes[3] = (byte) (data & 0xff);
        return bytes;
    }

    /**
     * 将long整型数值转换为字节数组(10进制)
     *
     * @param data
     * @return
     */
    public static byte[] getBytes(long data) {
        byte[] bytes = new byte[8];
        bytes[0] = (byte) ((data >> 56) & 0xff);
        bytes[1] = (byte) ((data >> 48) & 0xff);
        bytes[2] = (byte) ((data >> 40) & 0xff);
        bytes[3] = (byte) ((data >> 32) & 0xff);
        bytes[4] = (byte) ((data >> 24) & 0xff);
        bytes[5] = (byte) ((data >> 16) & 0xff);
        bytes[6] = (byte) ((data >> 8) & 0xff);
        bytes[7] = (byte) (data & 0xff);
        return bytes;
    }

    /**
     * 将float型数值转换为字节数组(10进制)
     *
     * @param data
     * @return
     */
    public static byte[] getBytes(float data) {
        int intBits = Float.floatToIntBits(data);
        return getBytes(intBits);
    }

    /**
     * 将double型数值转换为字节数组(10进制)
     *
     * @param data
     * @return
     */
    public static byte[] getBytes(double data) {
        long intBits = Double.doubleToLongBits(data);
        return getBytes(intBits);
    }

    /**
     * 将字符串按照charsetName编码格式的字节数组(10进制)
     *
     * @param data        字符串
     * @param charsetName 编码格式
     * @return
     */
    public static byte[] getBytes(String data, String charsetName) {
        Charset charset = Charset.forName(charsetName);
        return data.getBytes(charset);
    }

    /**
     * 将字符串按照GBK编码格式的字节数组(10进制)
     *
     * @param data
     * @return
     */
    public static byte[] getBytes(String data) {
        return getBytes(data, GBK);
    }

    /**
     * 将字节数组第0字节转换为布尔值(10进制)
     *
     * @param bytes
     * @return
     */
    public static boolean getBoolean(byte[] bytes) {
        return bytes[0] == 1;
    }

    /**
     * 将字节数组的第index字节转换为布尔值(10进制)
     *
     * @param bytes
     * @param index
     * @return
     */
    public static boolean getBoolean(byte[] bytes, int index) {
        return bytes[index] == 1;
    }

    /**
     * 将字节数组前2字节转换为short整型数值(10进制)
     *
     * @param bytes
     * @return
     */
    public static short getShort(byte[] bytes) {
        return (short) ((0xff00 & (bytes[0] << 8)) | (0xff & bytes[1]));
    }

    /**
     * 将字节数组从startIndex开始的2个字节转换为short整型数值(10进制)
     *
     * @param bytes
     * @param startIndex
     * @return
     */
    public static short getShort(byte[] bytes, int startIndex) {
        return (short) ((0xff00 & (bytes[startIndex] << 8)) | (0xff & bytes[startIndex + 1]));
    }

    /**
     * 将字节数组前2字节转换为字符(10进制)
     *
     * @param bytes
     * @return
     */
    public static char getChar(byte[] bytes) {
        return (char) ((0xff00 & (bytes[0] << 8)) | (0xff & bytes[1]));
    }

    /**
     * 将字节数组从startIndex开始的2个字节转换为字符(10进制)
     *
     * @param bytes
     * @param startIndex
     * @return
     */
    public static char getChar(byte[] bytes, int startIndex) {
        return (char) ((0xff00 & (bytes[startIndex] << 8)) | (0xff & bytes[startIndex + 1]));
    }

    /**
     * 将字节数组前4字节转换为整型数值(10进制)
     *
     * @param bytes
     * @return
     */
    public static int getInt(byte[] bytes) {
        bytes = formatByteArray(bytes, 4);
        return (0xff000000 & (bytes[0] << 24) | (0xff0000 & (bytes[1] << 16))
                | (0xff00 & (bytes[2] << 8)) | (0xff & bytes[3]));
    }

    /**
     * 将字节数组从startIndex开始的4个字节转换为整型数值(10进制)
     *
     * @param bytes
     * @param startIndex
     * @return
     */
    public static int getInt(byte[] bytes, int startIndex) {
        return (0xff000000 & (bytes[startIndex] << 24)
                | (0xff0000 & (bytes[startIndex + 1] << 16))
                | (0xff00 & (bytes[startIndex + 2] << 8)) | (0xff & bytes[startIndex + 3]));
    }

    /**
     * 将字节数组前8字节转换为long整型数值(10进制)
     *
     * @param bytes
     * @return
     */
    public static long getLong(byte[] bytes) {
        return (0xff00000000000000L & ((long) bytes[0] << 56)
                | (0xff000000000000L & ((long) bytes[1] << 48))
                | (0xff0000000000L & ((long) bytes[2] << 40))
                | (0xff00000000L & ((long) bytes[3] << 32))
                | (0xff000000L & ((long) bytes[4] << 24))
                | (0xff0000L & ((long) bytes[5] << 16))
                | (0xff00L & ((long) bytes[6] << 8)) | (0xffL & (long) bytes[7]));
    }

    /**
     * 将字节数组从startIndex开始的8个字节转换为long整型数值(10进制)
     *
     * @param bytes
     * @param startIndex
     * @return
     */
    public static long getLong(byte[] bytes, int startIndex) {
        return (0xff00000000000000L & ((long) bytes[startIndex] << 56)
                | (0xff000000000000L & ((long) bytes[startIndex + 1] << 48))
                | (0xff0000000000L & ((long) bytes[startIndex + 2] << 40))
                | (0xff00000000L & ((long) bytes[startIndex + 3] << 32))
                | (0xff000000L & ((long) bytes[startIndex + 4] << 24))
                | (0xff0000L & ((long) bytes[startIndex + 5] << 16))
                | (0xff00L & ((long) bytes[startIndex + 6] << 8)) | (0xffL & (long) bytes[startIndex + 7]));
    }

    /**
     * 将字节数组前4字节转换为float型数值(10进制)
     *
     * @param bytes
     * @return
     */
    public static float getFloat(byte[] bytes) {
        return Float.intBitsToFloat(getInt(bytes));
    }

    /**
     * 将字节数组从startIndex开始的4个字节转换为float型数值(10进制)
     *
     * @param bytes
     * @param startIndex
     * @return
     */
    public static float getFloat(byte[] bytes, int startIndex) {
        byte[] result = new byte[4];
        System.arraycopy(bytes, startIndex, result, 0, 4);
        return Float.intBitsToFloat(getInt(result));
    }

    /**
     * 将字节数组前8字节转换为double型数值(10进制)
     *
     * @param bytes
     * @return
     */
    public static double getDouble(byte[] bytes) {
        long l = getLong(bytes);
        return Double.longBitsToDouble(l);
    }

    /**
     * 将字节数组从startIndex开始的8个字节转换为double型数值(10进制)
     *
     * @param bytes
     * @param startIndex
     * @return
     */
    public static double getDouble(byte[] bytes, int startIndex) {
        byte[] result = new byte[8];
        System.arraycopy(bytes, startIndex, result, 0, 8);
        long l = getLong(result);
        return Double.longBitsToDouble(l);
    }

    /**
     * 将charsetName编码格式的字节数组转换为字符串(10进制)
     *
     * @param bytes
     * @param charsetName
     * @return
     */
    public static String getString(byte[] bytes, String charsetName) {
        return new String(bytes, Charset.forName(charsetName));
    }

    /**
     * 将UTF8编码格式的字节数组转换为字符串(10进制)
     *
     * @param bytes
     * @return
     */
    public static String getString(byte[] bytes) {
        return getString(bytes, UTF8);
    }


    /**
     * 将16进制字符串转换为字节数组使用
     *
     * @param c
     * @return
     */
    private static byte charToByte(char c) {
        return (byte) "0123456789ABCDEF".indexOf(c);
    }

    /**
     * 字节数组转16进制字符串
     *
     * @param bs
     * @return
     */
    public static String bytesToHex(byte[] bs) {
        StringBuilder sb = new StringBuilder();
        for (byte b : bs) {
            int high = (b >> 4) & 0x0f;
            int low = b & 0x0f;
            sb.append(HEX_VOCABLE[high]);
            sb.append(HEX_VOCABLE[low]);
        }
        return sb.toString();
    }

    /**
     * 字节数组取前len个字节转16进制字符串
     *
     * @param bs
     * @param len
     * @return
     */
    public static String bytesToHex(byte[] bs, int len) {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < len; i++) {
            byte b = bs[i];
            int high = (b >> 4) & 0x0f;
            int low = b & 0x0f;
            sb.append(HEX_VOCABLE[high]);
            sb.append(HEX_VOCABLE[low]);
        }
        return sb.toString();
    }

    /**
     * 字节数组偏移offset长度之后的取len个字节转16进制字符串
     *
     * @param bs
     * @param offset
     * @param len
     * @return
     */
    public static String bytesToHex(byte[] bs, int offset, int len) {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < len; i++) {
            byte b = bs[offset + i];
            int high = (b >> 4) & 0x0f;
            int low = b & 0x0f;
            sb.append(HEX_VOCABLE[high]);
            sb.append(HEX_VOCABLE[low]);
        }
        return sb.toString();
    }

    /**
     * 字节转整形
     *
     * @param value
     * @return
     */
    public static int bcdToInt(byte value) {
        return ((value >> 4) * 10) + (value & 0x0F);
    }


    /**
     * 将字节数组取反
     *
     * @param src
     * @return
     */
    public static String negate(byte[] src) {
        if (src == null || src.length == 0) {
            return null;
        }
        byte[] temp = new byte[2 * src.length];
        for (int i = 0; i < src.length; i++) {
            byte tmp = (byte) (0xFF ^ src[i]);
            temp[i * 2] = (byte) ((tmp >> 4) & 0x0f);
            temp[i * 2 + 1] = (byte) (tmp & 0x0f);
        }
        StringBuffer res = new StringBuffer();
        for (int i = 0; i < temp.length; i++) {
            res.append(ascii[temp[i]]);
        }
        return res.toString();
    }

    /**
     * 比较字节数组是否相同
     *
     * @param a
     * @param b
     * @return
     */
    public static boolean compareBytes(byte[] a, byte[] b) {
        if (a == null || a.length == 0 || b == null || b.length == 0
                || a.length != b.length) {
            return false;
        }
        if (a.length == b.length) {
            for (int i = 0; i < a.length; i++) {
                if (a[i] != b[i]) {
                    return false;
                }
            }
        } else {
            return false;
        }
        return true;
    }

    /**
     * 只比对指定长度byte
     *
     * @param a
     * @param b
     * @param len
     * @return
     */
    public static boolean compareBytes(byte[] a, byte[] b, int len) {
        if (a == null || a.length == 0 || b == null || b.length == 0
                || a.length < len || b.length < len) {
            return false;
        }
        for (int i = 0; i < len; i++) {
            if (a[i] != b[i]) {
                return false;
            }
        }
        return true;
    }

    /**
     * 将字节数组转换为二进制字符串
     *
     * @param items
     * @return
     */
    public static String bytesToBinaryString(byte[] items) {
        if (items == null || items.length == 0) {
            return null;
        }
        StringBuffer buf = new StringBuffer();
        for (byte item : items) {
            buf.append(byteToBinaryString(item));
        }
        return buf.toString();
    }

    /**
     * 将字节转换为二进制字符串
     *
     * @param item
     * @return
     */
    public static String byteToBinaryString(byte item) {
        byte a = item;
        StringBuffer buf = new StringBuffer();
        for (int i = 0; i < 8; i++) {
            buf.insert(0, a % 2);
            a = (byte) (a >> 1);
        }
        return buf.toString();
    }

    /**
     * 将short整型数值转换为字节数组
     *
     * @param num
     * @return
     */
    public static byte[] shortToBytes(short num) {
        byte[] temp = new byte[2];
        for (int i = 0; i < 2; i++) {
            temp[i] = (byte) ((num >>> (8 - i * 8)) & 0xFF);
        }
        return temp;
    }

    /**
     * 将字节数组转为整型
     *
     * @param arr
     * @return
     */
    public static int bytesToShort(byte[] arr) {
        int mask = 0xFF;
        int temp = 0;
        int result = 0;
        for (int i = 0; i < 2; i++) {
            result <<= 8;
            temp = arr[i] & mask;
            result |= temp;
        }
        return result;
    }

    /**
     * 将整型数值转换为指定长度的字节数组
     *
     * @param num
     * @return
     */
    public static byte[] intToBytes(int num) {
        byte[] temp = new byte[4];
        for (int i = 0; i < 4; i++) {
            temp[i] = (byte) ((num >>> (24 - i * 8)) & 0xFF);
        }
        return temp;
    }

    /**
     * 将整型数值转换为指定长度的字节数组
     *
     * @param src
     * @param len
     * @return
     */
    public static byte[] intToBytes(int src, int len) {
        if (len < 1 || len > 4) {
            return null;
        }
        byte[] temp = new byte[len];
        for (int i = 0; i < len; i++) {
            temp[len - 1 - i] = (byte) ((src >>> (8 * i)) & 0xFF);
        }
        return temp;
    }

    /**
     * 将字节数组转换为整型数值
     *
     * @param arr
     * @return
     */
    public static int bytesToInt(byte[] arr) {
        int mask = 0xFF;
        int temp = 0;
        int result = 0;
        for (int i = 0; i < 4; i++) {
            result <<= 8;
            temp = arr[i] & mask;
            result |= temp;
        }
        return result;
    }

    /**
     * 将long整型数值转换为字节数组
     *
     * @param num
     * @return
     */
    public static byte[] longToBytes(long num) {
        byte[] temp = new byte[8];
        for (int i = 0; i < 8; i++) {
            temp[i] = (byte) ((num >>> (56 - i * 8)) & 0xFF);
        }
        return temp;
    }

    /**
     * 将字节数组转换为long整型数值
     *
     * @param arr
     * @return
     */
    public static long bytesToLong(byte[] arr) {
        int mask = 0xFF;
        int temp = 0;
        long result = 0;
        int len = Math.min(8, arr.length);
        for (int i = 0; i < len; i++) {
            result <<= 8;
            temp = arr[i] & mask;
            result |= temp;
        }
        return result;
    }

    /**
     * 将16进制字符转换为字节
     *
     * @param c
     * @return
     */
    public static byte toByte(char c) {
        byte b = (byte) "0123456789ABCDEF".indexOf(c);
        return b;
    }

    /**
     * 功能描述:把两个字节的字节数组转化为整型数据,高位补零,
     * 有字节数组byte[] data = new byte[]{1,2};转换后int数据的字节分布如下:
     * 00000000  00000000 00000001 00000010,函数返回258
     *
     * @param lenData 需要进行转换的字节数组
     * @return 字节数组所表示整型值的大小
     */
    public static int bytesToIntWhereByteLengthEquals2(byte lenData[]) {
        if (lenData.length != 2) {
            return -1;
        }
        byte fill[] = new byte[]{0, 0};
        byte real[] = new byte[4];
        System.arraycopy(fill, 0, real, 0, 2);
        System.arraycopy(lenData, 0, real, 2, 2);
        int len = byteToInt(real);
        return len;

    }

    /**
     * 功能描述:将byte数组转化为int类型的数据
     *
     * @param byteVal 需要转化的字节数组
     * @return 字节数组所表示的整型数据
     */
    public static int byteToInt(byte[] byteVal) {
        int result = 0;
        for (int i = 0; i < byteVal.length; i++) {
            int tmpVal = (byteVal[i] << (8 * (3 - i)));
            switch (i) {
                case 0:
                    tmpVal = tmpVal & 0xFF000000;
                    break;
                case 1:
                    tmpVal = tmpVal & 0x00FF0000;
                    break;
                case 2:
                    tmpVal = tmpVal & 0x0000FF00;
                    break;
                case 3:
                    tmpVal = tmpVal & 0x000000FF;
                    break;
            }

            result = result | tmpVal;
        }
        return result;
    }

    public static byte CheckXORSum(byte[] bData) {
        byte sum = 0x00;
        for (int i = 0; i < bData.length; i++) {
            sum ^= bData[i];
        }
        return sum;
    }

    /**
     * 从offset开始 将后续长度为len的byte字节转为int
     *
     * @param data
     * @param offset
     * @param len
     * @return
     */
    public static int bytesToInt(byte[] data, int offset, int len) {
        int mask = 0xFF;
        int temp = 0;
        int result = 0;
        len = Math.min(len, 4);
        for (int i = 0; i < len; i++) {
            result <<= 8;
            temp = data[offset + i] & mask;
            result |= temp;
        }
        return result;
    }

    /**
     * byte字节数组中的字符串的长度
     *
     * @param data
     * @return
     */
    public static int getBytesStringLen(byte[] data) {
        int count = 0;
        for (byte b : data) {
            if (b == 0x00) {
                break;
            }
            count++;
        }
        return count;
    }

    /**
     * byte数组补位
     */
    public static byte[] formatByteArray(byte[] bytes, int length) {
        int bytelength = length - bytes.length;
        int baseByteLenth = bytelength;
        if (bytelength > 0) {
            int index = 0;
            byte[] result = new byte[length];
            while (bytelength > 0) {
                result[index] = 0;
                index++;
                bytelength--;
            }
            for (int i = index; i < length; i++) {
                result[i] = bytes[i - baseByteLenth];
            }

            return result;
        } else {
            return bytes;
        }
    }

    /**
     * byte数组转int数组
     *
     * @param btarr
     * @return
     */
    public static int[] byteArrayToIntArray(byte[] btarr) {
        if (btarr.length % 4 != 0) {
            return null;
        }
        int[] intarr = new int[btarr.length / 4];

        int i1, i2, i3, i4;
        for (int j = 0, k = 0; j < intarr.length; j++, k += 4)//j循环int		k循环byte数组
        {
            i1 = btarr[k];
            i2 = btarr[k + 1];
            i3 = btarr[k + 2];
            i4 = btarr[k + 3];

            if (i1 < 0) {
                i1 += 256;
            }
            if (i2 < 0) {
                i2 += 256;
            }
            if (i3 < 0) {
                i3 += 256;
            }
            if (i4 < 0) {
                i4 += 256;
            }
            intarr[j] = (i1 << 24) + (i2 << 16) + (i3 << 8) + (i4 << 0);
        }
        return intarr;
    }

    /**
     * byte数组转int数组
     *
     * @param btarr
     * @return
     */
    public static long[] byteArrayToUintArray(byte[] btarr) {
        if (btarr.length % 4 != 0) {
            return null;
        }
        long[] intarr = new long[btarr.length / 4];

        int i1, i2, i3, i4;
        for (int j = 0, k = 0; j < intarr.length; j++, k += 4)//j循环int		k循环byte数组
        {
            i1 = btarr[k];
            i2 = btarr[k + 1];
            i3 = btarr[k + 2];
            i4 = btarr[k + 3];

            if (i1 < 0) {
                i1 += 256;
            }
            if (i2 < 0) {
                i2 += 256;
            }
            if (i3 < 0) {
                i3 += 256;
            }
            if (i4 < 0) {
                i4 += 256;
            }
            intarr[j] = ((i1 << 24) + (i2 << 16) + (i3 << 8) + (i4 << 0)) & 0xFFFFFFFFL;
        }
        return intarr;
    }

    /**
     * int数组转byte数组
     *
     * @param intarr
     * @return
     */
    public static byte[] intArrayToByteArray(int[] intarr) {
        int bytelength = intarr.length * 4;//长度
        byte[] bt = new byte[bytelength];//开辟数组
        int curint = 0;
        for (int j = 0, k = 0; j < intarr.length; j++, k += 4) {
            curint = intarr[j];
            bt[k] = (byte) ((curint >> 24) & 0b1111_1111);//右移4位,与1作与运算
            bt[k + 1] = (byte) ((curint >> 16) & 0b1111_1111);
            bt[k + 2] = (byte) ((curint >> 8) & 0b1111_1111);
            bt[k + 3] = (byte) ((curint >> 0) & 0b1111_1111);
        }
        return bt;
    }

    /**
     * 10进制转16进制(byte)
     *
     * @param value
     * @return
     */
    public static byte[] toHexByte(Byte value) {
        return formatByteArray(getBytesByHex(byteToHex(value)), 1);
    }

    /**
     * 10进制转16进制(short)
     *
     * @param value
     * @return
     */
    public static byte[] toHexByte(Short value) {
        return formatByteArray(getBytesByHex(shortToHex(value)), 2);
    }

    /**
     * 10进制转16进制(int)
     *
     * @param value
     * @return
     */
    public static byte[] toHexByte(Integer value) {
        return formatByteArray(getBytesByHex(Integer.toHexString(value)), 4);
    }

    /**
     * 10进制转16进制(value)
     *
     * @param value
     * @return
     */
    public static byte[] toHexByte(Long value) {
        return formatByteArray(getBytesByHex(Long.toHexString(value)), 8);
    }

    /**
     * 10进制字符串转16进制数组
     *
     * @param value
     * @param byteArrayLength
     * @return
     */
    public static byte[] toHexByte(String value, int byteArrayLength) {
        return formatByteArray(getBytesByHex(strToHex(value)), byteArrayLength);
    }

    /**
     * 字符串转换成为16进制(无需Unicode编码)
     *
     * @param value
     * @return
     */
    public static String strToHex(String value) {
        char[] chars = "0123456789ABCDEF".toCharArray();
        StringBuilder sb = new StringBuilder("");
        byte[] bs = value.getBytes();
        int bit;
        for (int i = 0; i < bs.length; i++) {
            bit = (bs[i] & 0x0f0) >> 4;
            sb.append(chars[bit]);
            bit = bs[i] & 0x0f;
            sb.append(chars[bit]);
        }
        return sb.toString().trim();
    }


    /**
     * 字节转16进制字符串
     *
     * @param b
     * @return
     */
    public static String byteToHex(byte b) {
        StringBuilder sb = new StringBuilder();
        int high = (b >> 4) & 0x0f;
        int low = b & 0x0f;
        sb.append(HEX_VOCABLE[high]);
        sb.append(HEX_VOCABLE[low]);
        return sb.toString();
    }

    /**
     * short转16进制字符串
     *
     * @param b
     * @return
     */
    public static String shortToHex(short b) {
        return bytesToHex(shortToBytes(b));
    }

    /**
     * int转换成为16进制
     *
     * @param value
     * @return
     */
    public static String strToHex(int value) {
        return Integer.toHexString(value);
    }

    /**
     * long转换成为16进制
     *
     * @param value
     * @return
     */
    public static String strToHex(long value) {
        return Long.toHexString(value);
    }

    /**
     * 字节数组循环拼接string
     *
     * @return
     */
    public static String byteToString(byte[] byteValue) {
        String value = "";
        for (int i = 0; i < byteValue.length; i++) {
            value += byteValue[i];
        }
        return value;
    }

    /**
     * string字符串循环byte[]
     *
     * @param strValue
     * @return
     */
    public static byte[] stringToByte(String strValue) {
        byte[] value = new byte[strValue.length()];
        for (int i = 0; i < strValue.length(); i++) {
            value[i] = Byte.valueOf(String.valueOf(strValue.charAt(i)));
        }
        return value;
    }


    /**
     * 字节数组转成16进制表示格式的字符串
     *
     * @param byteArray 需要转换的字节数组
     * @return 16进制表示格式的字符串
     */
    public static String toHexString(byte[] byteArray) {
        if (byteArray == null || byteArray.length < 1)
            throw new IllegalArgumentException("this byteArray must not be null or empty");
        final StringBuilder hexString = new StringBuilder();
        for (int i = 0; i < byteArray.length; i++) {
            if ((byteArray[i] & 0xff) < 0x10) // 0~F前面不零
                hexString.append("0");
            hexString.append(Integer.toHexString(0xFF & byteArray[i]));
        }
        return hexString.toString().toLowerCase();
    }


    /**
     * 将16进制字符串转换为字节数组
     *
     * @param hex
     * @return
     */
    public static byte[] getBytesByHex(String hex) {
        if (hex == null || hex.equals("")) {
            return null;
        }
        hex = hex.toUpperCase();
        int length = hex.length() / 2;
        char[] hexChars = hex.toCharArray();
        byte[] d;
        //转换的时候应该注意的是单双数的情况,网上很多都只处理了双数的情况,也就是默认刚好填满,这样16进制字符串长度是单数的话会丢失掉一个字符 因为length/2 是舍去余数的
        if (hex.length() % 2 != 0) {// 16进制字符串长度是单数
            length = length + 1;
            d = new byte[length];
            // 这里把byte数组从后往前填,字符串也是翻转着填的,最后会空出byte数组的第一个(用来填充我们单出来的那个字符)
            for (int i = length - 1; i > 0; i--) {
                int pos = i * 2;
                d[i] = (byte) (charToByte(hexChars[pos]) | charToByte(hexChars[pos - 1]) << 4);
            }
            d[0] = charToByte(hexChars[0]);
        } else {// 双数情况
            d = new byte[length];
            for (int i = 0; i < length; i++) {
                int pos = i * 2;
                d[i] = (byte) (charToByte(hexChars[pos]) << 4 | charToByte(hexChars[pos + 1]));
            }
        }
        return d;
    }
}

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