字符串，int,十六进制相互转换

拼搏现实的明天。 2022-06-03 01:45 262阅读 0赞

public class TypeConvert {   
        /* 字符串转byte[] 这个方法转换后的结果是会多一些 48字符进来的就是代表的是0不知道为什么，但是可以只是取出指定的字符串 */  
      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;  
    }  
    
        /* byte转short */  
        public final static short getShort(byte[] buf, boolean asc, int len) {  
            short r = 0;  
            if (asc)  
              for (int i = len - 1; i >= 0; i--) {  
                r <<= 8;  
                r |= (buf[i] & 0x00ff);  
              }  
            else  
              for (int i = 0; i < len; i++) {  
                r <<= 8;  
                r |= (buf[i] & 0x00ff);  
              }  
    
            return r;  
       }  
    
        /* B2 -> 0xB2 */  
        public static int stringToByte(String in, byte[] b) throws Exception {   
           if (b.length < in.length() / 2) {   
                throw new Exception("byte array too small");   
            }  
    
            int j=0;  
           StringBuffer buf = new StringBuffer(2);   
           for (int i=0; i<in.length(); i++, j++) {   
               buf.insert(0, in.charAt(i));   
                buf.insert(1, in.charAt(i+1));   
                int t = Integer.parseInt(buf.toString(),16);   
                System.out.println("byte hex value:" + t);   
                b[j] = (byte)t;  
                i++;   
                buf.delete(0,2);   
            }   
    
            return j;  
        }  
    
        /* byte to int */  
       public final static int getInt(byte[] buf, boolean asc, int len) {  
            if (buf == null) {  
              throw new IllegalArgumentException("byte array is null!");  
           }  
            if (len > 4) {  
              throw new IllegalArgumentException("byte array size > 4 !");  
            }  
            int r = 0;  
            if (asc)  
              for (int i = len - 1; i >= 0; i--) {  
                r <<= 8;  
                r |= (buf[i] & 0x000000ff);  
              }  
            else  
              for (int i = 0; i < len; i++) {  
                r <<= 8;  
                r |= (buf[i] & 0x000000ff);  
              }  
           return r;  
        }  
    
       /* int -> byte[] */  
        public static byte[] intToBytes(int num) {  
           byte[] b = new byte[4];  
          for (int i = 0; i < 4; i++) {  
           b[i] = (byte) (num >>> (24 - i * 8));  
           }  
    
           return b;  
        }  
    
        /* short to byte[] */  
        public static byte[] shortToBytes(short num) {  
          byte[] b = new byte[2];  
    
          for (int i = 0; i < 2; i++) {  
               b[i] = (byte) (num >>> (i * 8));  
           }  
    
         return b;  
        }  
    
        /* byte to String */  
       private static char findHex(byte b) {   
            int t = new Byte(b).intValue();   
           t = t < 0 ? t + 16 : t;   
    
           if ((0 <= t) &&(t <= 9)) {   
           return (char)(t + '0');   
           }   
    
            return (char)(t-10+'A');   
        }   
        public static String byteToString(byte b) {   
            byte high, low;   
            byte maskHigh = (byte)0xf0;   
            byte maskLow = 0x0f;   
    
            high = (byte)((b & maskHigh) >> 4);   
            low = (byte)(b & maskLow);   
    
            StringBuffer buf = new StringBuffer();   
            buf.append(findHex(high));   
            buf.append(findHex(low));   
    
           return buf.toString();   
        }  
    
       /* short -> byte */  
        public final static byte[] getBytes(short s, boolean asc) {  
           byte[] buf = new byte[2];  
           if (asc)      for (int i = buf.length - 1; i >= 0; i--) {  buf[i] = (byte) (s & 0x00ff);  
               s >>= 8;  
              }  
           else  
             for (int i = 0; i < buf.length; i++) {  
              buf[i] = (byte) (s & 0x00ff);  
                s >>= 8;  
             }  
           return buf;  
         }  
        /* int -> byte[] */  
          public final static byte[] getBytes(int s, boolean asc) {  
            byte[] buf = new byte[4];  
           if (asc)  
              for (int i = buf.length - 1; i >= 0; i--) {  
                buf[i] = (byte) (s & 0x000000ff);  
               s >>= 8;  
             }  
           else  
            for (int i = 0; i < buf.length; i++) {  
                buf[i] = (byte) (s & 0x000000ff);  
                s >>= 8;  
              }  
            return buf;  
         }  
    
         /* long -> byte[] */  
          public final static byte[] getBytes(long s, boolean asc) {  
           byte[] buf = new byte[8];  
            if (asc)  
             for (int i = buf.length - 1; i >= 0; i--) {  
               buf[i] = (byte) (s & 0x00000000000000ff);  
                s >>= 8;  
              }  
            else  
              for (int i = 0; i < buf.length; i++) {  
                buf[i] = (byte) (s & 0x00000000000000ff);  
                s >>= 8;  
              }  
            return buf;  
         }  
    
          /* byte[]->int */  
          public final static int getInt(byte[] buf, boolean asc) {  
            if (buf == null) {  
             throw new IllegalArgumentException("byte array is null!");  
           }  
            if (buf.length > 4) {  
              throw new IllegalArgumentException("byte array size > 4 !");  
            }  
           int r = 0;  
            if (asc)  
              for (int i = buf.length - 1; i >= 0; i--) {  
                r <<= 8;  
               r |= (buf[i] & 0x000000ff);  
              }  
            else  
              for (int i = 0; i < buf.length; i++) {  
              r <<= 8;  
               r |= (buf[i] & 0x000000ff);  
              }  
            return r;  
         }  
         /* byte[] -> long */  
          public final static long getLong(byte[] buf, boolean asc) {  
            if (buf == null) {  
              throw new IllegalArgumentException("byte array is null!");  
           }  
            if (buf.length > 8) {  
             throw new IllegalArgumentException("byte array size > 8 !");  
            }  
            long r = 0;  
            if (asc)  
              for (int i = buf.length - 1; i >= 0; i--) {  
                r <<= 8;  
               r |= (buf[i] & 0x00000000000000ff);  
             }  
            else  
              for (int i = 0; i < buf.length; i++) {  
               r <<= 8;  
                r |= (buf[i] & 0x00000000000000ff);  
              }  
            return r;  
          }  
    }