Java 進制轉換

前言

　　提供java和工具類轉換

人工計算

16進制轉10進制

了解字母取代的數字

A=10

B=11  

C=12  

D=13  

E=14  

F=15

AB13 轉成10進制,從遞增次方低位計算

3 * 16^0 =  3

1 * 16^1 =  16

11 * 16^2 = 2816

10 * 16^3 = 40960

3 + 16 + 2816 +40960 = 43795

Java原生轉換

十進制轉化成十六進制字符串

int var = 324;
String hex = Integer.toHexString(var);
long lvar = 3243143432134L;
String lhex = Long.toHexString(lvar);

十六進制字符串轉化成十進制整數

Integer.parseInt(hex, 16);
Long.parseLong(hex, 16);

    /**
     * parseInt("0", 10) returns 0
     * parseInt("473", 10) returns 473
     * parseInt("+42", 10) returns 42
     * parseInt("-0", 10) returns 0
     * parseInt("-FF", 16) returns -255
     * parseInt("1100110", 2) returns 102
     * parseInt("2147483647", 10) returns 2147483647
     * parseInt("-2147483648", 10) returns -2147483648
     * parseInt("2147483648", 10) throws a NumberFormatException
     * parseInt("99", 8) throws a NumberFormatException
     * parseInt("Kona", 10) throws a NumberFormatException
     * parseInt("Kona", 27) returns 411787
     */

負數十六進制字符串轉十進制

BigInteger bi = new BigInteger(hex, 16);
bi.intValue(); 
bi.longValue(); 

 

工具類

package cn.hawk.bluetoothlib.utils;

import android.util.Log;

import com.clj.fastble.utils.HexUtil;

import java.math.BigInteger;

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;

/**
 * Created by kehaowei on 2017/10/27.
 */

public class HexHelper {
    /**
     * 數字轉16進制字符串
     * @param input
     * @return
     */
    public static String number2HexStr(String input) {
        String output = "";
        if (input.length() % 2 != 0)
            input += "0";
        int count = input.length() / 2;
        for (int i = 0; i < count; i++) {
            String sub = input.substring(i * 2, i * 2 + 2);
            int num = getIntSafely(sub);
            output += int2Hex(num);
        }
        return output;
    }

    /**
     * 16進制字符串轉數字
     * @param input
     * @return
     */
    public static String hexStr2number(String input) {
        String output = "";
        if (input.length() % 2 != 0)
            input += "0";
        int count = input.length() / 2;
        for (int i = 0; i < count; i++) {
            String sub = input.substring(i * 2, i * 2 + 2);
            int temp = hexChar2int(sub.substring(0, 1)) * 16 + hexChar2int(sub.substring(1, 2));
            if (temp < 10) {
                output += "0" + temp;
            } else {
                output += temp + "";
            }
        }
        return output;
    }

    /**
     * 16進制字符串轉10進制
     * @param input
     * @return
     */
    public static int hexStr2Int(String input) {
        int output = 0;
        int count = input.length();
        for (int i = 0; i < count; i++) {
            String sub = input.substring(i, i + 1);
            int temp = (int) (hexChar2int(sub) * Math.pow(16, count - 1 - i));
            output += temp;
        }
        return output;
    }

    /**
     * 16進制字符串轉10進制
     * @param input
     * @return
     */
    public static long hexStr2Long(String input) {
        long output = 0;
        int count = input.length();
        for (int i = 0; i < count; i++) {
            String sub = input.substring(i, i + 1);
            long temp = (long) (hexChar2int(sub) * Math.pow(16, count - 1 - i));
            output += temp;
        }
        return output;
    }

    /**
     * 安全的獲取整數
     * @param str
     * @return
     */
    public static int getIntSafely(String str) {
        int result = 0;
        try {
            result = Integer.parseInt(str);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return result;
    }

    /**
     * 10進制轉16進制
     * @param input
     * @return
     */
    public static String int2Hex(int input) {
        String result = "";
        if (input < 16) {
            result = "0" + intChar2Hex(input);
        } else {
            result = intChar2Hex(input / 16) + intChar2Hex(input % 16);
        }
        return result;
    }

    /**
     * 整數轉16進制
     * @param input
     * @return
     */
    public static String intChar2Hex(int input) {
        String result = "0";
        if (input < 10)
            result = "" + input;
        else {
            switch (input) {
                case 10:
                    result = "A";
                    break;
                case 11:
                    result = "B";
                    break;
                case 12:
                    result = "C";
                    break;
                case 13:
                    result = "D";
                    break;
                case 14:
                    result = "E";
                    break;
                case 15:
                    result = "F";
                    break;
            }
        }
        return result;
    }

    public static final String bytesToHexString(byte[] bArray) {
        StringBuffer sb = new StringBuffer(bArray.length);
        String sTemp;
        for (int i = 0; i < bArray.length; i++) {
            sTemp = Integer.toHexString(0xFF & bArray[i]);
            if (sTemp.length() < 2)
                sb.append(0);
            sb.append(sTemp.toUpperCase());
        }
        return sb.toString();
    }

    /**
     * 16進制字符轉整數
     * @param input
     * @return
     */
    public static int hexChar2int(String input) {
        int result = 0;
        try {
            result = Integer.parseInt(input);
        } catch (Exception e) {
            if (input.equalsIgnoreCase("A"))
                result = 10;
            else if (input.equalsIgnoreCase("B"))
                result = 11;
            else if (input.equalsIgnoreCase("C"))
                result = 12;
            else if (input.equalsIgnoreCase("D"))
                result = 13;
            else if (input.equalsIgnoreCase("E"))
                result = 14;
            else if (input.equalsIgnoreCase("F"))
                result = 15;
        }
        return result;
    }

    //使用1字節就可以表示b
    public static String numToHex8(int b) {
        return String.format("%02x", b);//2表示需要兩個16進行數
    }

    //需要使用2字節表示b
    public static String numToHex16(int b) {
        return String.format("%04x", b);
    }
    //需要使用4字節表示b
    public static String numToHex32(int b) {
        return String.format("%08x", b);
    }


    /**
     * 獲取高四位
     *
     * @param data
     * @return
     */
    public static int getHeight4(byte data) {
        int height;
        height = ((data & 0xf0) >> 4);
        return height;
    }

    /**
     * 獲取低四位
     *
     * @param data
     * @return
     */
    public static int getLow4(byte data) {
        int low;
        low = (data & 0x0f);
        return low;
    }
    /**
     * c-byte數組轉換成java-int值 <br/> 高位在前 <br/> [24 - 16 - 08 - 00]
     *
     * @param buffer byte數組
     * @param index  轉換開始位置
     * @param len    轉換的長度
     */
    public static int cbyte2intHigh(byte[] buffer, int index, int len) {
        if (buffer == null || index + len > buffer.length) {
            return 0;
        }
        int value = 0;
        for (int i = 0, j = len - 1; i < len; i++, j--) {
            value += (cbyte2Int(buffer[i + index]) << (j * 8));
        }
        return value;
    }



    /**
     * c無符號的值，轉換成java-int值
     */
    public static int cbyte2Int(byte byteNum) {
        return byteNum & 0xff;
    }

    /**
     * 計算CRC16校驗碼
     *
     * @param bytes
     * @return
     */
    public static String getCRC(byte[] bytes) {
        int CRC =CRC16Util.CRC16(bytes);
        System.out.println("getCRC CRC = "+ CRC);
        return numToHex16(CRC);
//        return CRC16Util.getCRC(bytes);
    }

    public static byte[] byteMerger(byte[] bt1, byte[] bt2){
        byte[] bt3 = new byte[bt1.length+bt2.length];
        System.arraycopy(bt1, 0, bt3, 0, bt1.length);
        System.arraycopy(bt2, 0, bt3, bt1.length, bt2.length);
        return bt3;
    }

    /**
     * 十六進制轉換字符串
     * @return String 對應的字符串
     */
    public static String hexStr2Str(String hexStr)
    {
        String str = "0123456789ABCDEF";
        char[] hexs = hexStr.toCharArray();
        byte[] bytes = new byte[hexStr.length() / 2];
        int n;

        for (int i = 0; i < bytes.length; i++)
        {
            n = str.indexOf(hexs[2 * i]) * 16;
            n += str.indexOf(hexs[2 * i + 1]);
            bytes[i] = (byte) (n & 0xff);
        }
        return new String(bytes);
    }

    /**
     * 字節數組轉版本號
     */
    public static String hexStr2Version(String input){
        int[] ints = new int[4];
        String output = "";
        if (input.length() % 2 != 0)
            input += "0";
        int count = input.length() / 2;
        for (int i = 0; i < count; i++) {
            String sub = input.substring(i * 2, i * 2 + 2);
            int temp = hexChar2int(sub.substring(0, 1)) * 16 + hexChar2int(sub.substring(1, 2));
            ints[i]=temp;
        }
        return String.format("%d.%d.%d.%d",ints[0],ints[1],ints[2],ints[3]);
    }


    public static String hexXOR(String hex1, String hex2){
        BigInteger i1 = new BigInteger(hex1, 16);
        BigInteger i2 = new BigInteger(hex2, 16);
        BigInteger res = i1.xor(i2);
        return res.toString(16).toUpperCase();
    }


    // 加密
    public static  byte[] Encrypt(String sSrc, String sKey) throws Exception {
        if (sKey == null) {
            System.out.print("Key為空null");
            return null;
        }
        // 判斷Key是否為16位
        if (sKey.length() != 16) {
            System.out.print("Key長度不是16位");
            return null;
        }
        byte[] raw = sKey.getBytes("utf-8");
        SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
        Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");//"算法/模式/補碼方式"
        cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
        byte[] encrypted = cipher.doFinal(sSrc.getBytes("utf-8"));

        return encrypted;
    }
    // 加密
    public static  byte[] Encrypt(byte[] sSrc,  byte[] aesEncrypt) throws Exception {
        if (aesEncrypt == null) {
            System.out.print("Key為空null");
            return null;
        }
        // 判斷Key是否為16位
       /* if (sKey.length() != 16) {
            System.out.print("Key長度不是16位");
            return null;
        }*/
        byte[] raw = aesEncrypt;
        SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
        Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");//"算法/模式/補碼方式"
        cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
        byte[] encrypted = cipher.doFinal(sSrc);

        return encrypted;
    }



    /**
     * 基於Sn的異或加密
     */
    public static String getXOR_DATA(String ly2Package,String deviceSn){
        int ly2packLength=ly2Package.length();
        //得到sn前四位
        String getStart4 = deviceSn.substring(0, 4);
        //得到sn后16位
        String  getLast16=deviceSn.substring(4,deviceSn.length());

        String last16Hex = HexUtil.encodeHexStr(getLast16.getBytes());

        String result1 = XOR(ly2Package, ly2packLength, last16Hex);
        if (result1 != null) return result1;
        return "";

    }


    public static String XOR(String content, int cotentLength, String keyHex) {
        int keyHexLength=keyHex.length();

        String result=keyHex;

        if(keyHexLength>cotentLength){
            result= keyHex.substring(0,cotentLength);
        }else {
            int add = cotentLength - keyHexLength;


            int count = add / keyHexLength;
            int remainder = add % keyHexLength;//余數


            for (int i = 0; i <count ; i++) {
                result= result+keyHex;
            }

            if (remainder!=0){
                result= result + keyHex.substring(0, remainder);
            }

        }

        if (result.length()==cotentLength){
            //進行異或
            Log.e("進行異或result:",result);
            Log.e("進行異或content:",content);
            String hexXOR = HexHelper.hexXOR(result, content);
            if (hexXOR.length()!=cotentLength){
                int absCount = Math.abs(cotentLength-hexXOR.length());
                for (int i = 0; i < absCount; i++) {
                    hexXOR="0"+hexXOR;
                }
                return hexXOR;
            }
            return hexXOR;
        }
        return null;
    }

    public static  String timeStr2Hex(String time){
        String result="" ;
        int length = time.length() / 2;
        int j=0;
        for (int i = 0; i < length; i++) {
            String oneStr = numToHex8(Integer.parseInt(time.substring(j, j+2)));
            j+=2;
            if (oneStr.length()==1){
                oneStr="0"+oneStr;
            }
            result=result+oneStr;
        }
        return result;
    }
}

 bytes轉換

package net.wt.gate.ui.activity.bleLight;

public class TransformUtil {

    /*
     * Convert byte[] to hex string.這里我們可以將byte轉換成int，然后利用Integer.toHexString(int)來轉換成16進制字符串。
     * @param src byte[] data
     * @return hex string
     */
    public static String bytesToHexString(byte[] src) {
        StringBuilder stringBuilder = new StringBuilder("");
        if (src == null || src.length <= 0) {
            return null;
        }
        for (int i = 0; i < src.length; i++) {
            int v = src[i] & 0xFF;
            String hv = Integer.toHexString(v);
            if (hv.length() < 2) {
                stringBuilder.append(0);
            }
            stringBuilder.append(hv);
        }
        return stringBuilder.toString();
    }

    /**
     * Convert hex string to byte[]
     *
     * @param hexString the hex string
     * @return byte[]
     */
    public static byte[] hexStringToBytes(String hexString) {
        if (hexString == null || hexString.equals("")) {
            return null;
        }
        hexString = hexString.toUpperCase();
        int length = hexString.length() / 2;
        char[] hexChars = hexString.toCharArray();
        byte[] 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;
    }

    public static byte[] int2Bytes(int num) {
        byte[] byteNum = new byte[4];
        for (int ix = 0; ix < 4; ++ix) {
            int offset = 32 - (ix + 1) * 8;
            byteNum[ix] = (byte) ((num >> offset) & 0xff);
        }
        return byteNum;
    }

    public static int bytes2Int(byte[] byteNum) {
        int num = 0;
        for (int ix = 0; ix < 4; ++ix) {
            num <<= 8;
            num |= (byteNum[ix] & 0xff);
        }
        return num;
    }

    public static byte int2OneByte(int num) {
        return (byte) (num & 0x000000ff);
    }

    public static int oneByte2Int(byte byteNum) {
        return byteNum > 0 ? byteNum : (128 + (128 + byteNum));
    }

    public static byte[] long2Bytes(long num) {
        byte[] byteNum = new byte[8];
        for (int ix = 0; ix < 8; ++ix) {
            int offset = 64 - (ix + 1) * 8;
            byteNum[ix] = (byte) ((num >> offset) & 0xff);
        }
        return byteNum;
    }

    public static long bytes2Long(byte[] byteNum) {
        long num = 0;
        for (int ix = 0; ix < 8; ++ix) {
            num <<= 8;
            num |= (byteNum[ix] & 0xff);
        }
        return num;
    }

    /**
     * Convert char to byte
     *
     * @param c char
     * @return byte
     */
    private static byte charToByte(char c) {
        return (byte) "0123456789ABCDEF".indexOf(c);
    }
}