Byte[] 转换截取等操作

痛定思痛。 2022-03-06 15:16 228阅读 0赞

1、工作中用到的与Byte\[\]相关方法工具类。记录一下

包含：16进制字符串转换Byte\[\]、Byte\[\]转换成16进制字符、字符串转换成十六进制字符串、16进制直接转换成为字符串(无需Unicode解码)、校验和、Byte\[\]截取指定长度数组、BCD码转为10进制串(阿拉伯数据)、int与byte 互转、byte\[\]转int高低位互换、

byte\[\]转int 、byte\[\]与short 互转、10进制串转为BCD码

/**
          * 把16进制字符串转换成字节数组
          * @param hexString
          * @return byte[]
          */
    	  public static byte[] hexStringToByte(String hex) {
              if ((hex == null) || (hex.equals(""))){
                  return null;
              }
              else if (hex.length()%2 != 0){
                  return null;
              }
              else{                
                  hex = hex.toUpperCase();
                  int len = hex.length()/2;
                  byte[] b = new byte[len];
                  char[] hc = hex.toCharArray();
                  for (int i=0; i<len; i++){
                      int p=2*i;
                      b[i] = (byte) (charToByte(hc[p]) << 4 | charToByte(hc[p+1]));
                  }
                return b;
              }           
    
    	  }
    	  
    	  private static int charToByte(char c) {
    		   byte b = (byte) "0123456789ABCDEF".indexOf(c);
    		   return b;
    	  }
    
    	  /**
    	   * 字节数组转换成16进制字符
    	   * @param hint
    	   * @param b
    	   * @return
    	   */
    	  public static  String printHexString(String hint, byte[] b) {
    			String str = "";
    			int size=b.length;
    			for (int i = 0; i < size; i++) {
    				String hex = Integer.toHexString(b[i] & 0xFF);
    				if (hex.length() == 1) {
    					hex = '0' + hex;
    				}
    				str += hex.toUpperCase();
    			}
    			return hint+ str;
    	  }
    	 
    	  /** 
    	    * 字符串转换成十六进制字符串
    	    */  
    	  public static String str2HexStr(String str) {  
    	      char[] chars = "0123456789ABCDEF".toCharArray();  
    	      StringBuilder sb = new StringBuilder("");
    	      byte[] bs = str.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();  
    	  } 
    	 
    	  
    	  /**
    	   * 16进制直接转换成为字符串(无需Unicode解码)
    	   * @param hexStr
    	   * @return
    	   */
    	  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);
    	  }
     
    	 /**
    	  * 校验和
    	  * @param data
    	  * @return
    	  */
    	 public static String makeChecksum(String data) {
    			 if (data == null || data.equals("")) {
    			  return "";
    			 }
    			 int total = 0;
    			 int len = data.length();
    			 int num = 0;
    			 while (num < len) {
    			  String s = data.substring(num, num + 2);
    			  total += Integer.parseInt(s, 16);
    			  num = num + 2;
    			 }
    			 /**
    			  * 用256求余最大是255，即16进制的FF
    			  */
    			 int mod = total % 256;
    			 String hex = Integer.toHexString(mod);
    			 len = hex.length();
    			 // 如果不够校验位的长度，补0,这里用的是两位校验
    			 if (len < 2) {
    			  hex = "0" + hex;
    			 }
    			 return hex.toUpperCase();
    	  }
    
    	 /**
    	  * 截取指定长度数组
    	  * @param src
    	  * @param begin
    	  * @param count
    	  * @return
    	  */
    	 public static byte[] subBytes(byte[] src, int begin, int count) {  
    		    byte[] bs = new byte[count];  
    		    System.arraycopy(src, begin, bs, 0, count);  
    		    return bs;  
    	}  
    	 
    	
    	/**
    	 * @功能: BCD码转为10进制串(阿拉伯数据)
    	 * @参数: BCD码
    	 * @结果: 10进制串
    	 */
    	public static String bcd2Str(byte[] bytes) {
    		StringBuffer temp = new StringBuffer(bytes.length * 2);
    		for (int i = 0; i < bytes.length; i++) {
    			temp.append((byte) ((bytes[i] & 0xf0) >>> 4));
    			temp.append((byte) (bytes[i] & 0x0f));
    		}
    		return temp.toString().substring(0, 1).equalsIgnoreCase("0") ? temp
    				.toString().substring(1) : temp.toString();
    	}
    	 
    	 
         /** 
          * int转byte 
          * @param x 
          * @return 
          */  
        public static byte intToByte(int x) {    
            return (byte) x;    
        }    
        /** 
         * byte转int 
         * @param b 
         * @return 
         */  
        public static int byteToInt(byte b) {    
            //Java的byte是有符号，通过 &0xFF转为无符号  
            return b & 0xFF;    
        }    
            
        /** 
         * byte[]转int 
         * @param b 
         * @return 
         */  
        public static int byteArrayToInt(byte[] b) {    
            return   b[3] & 0xFF |    
                    (b[2] & 0xFF) << 8 |    
                    (b[1] & 0xFF) << 16 |    
                    (b[0] & 0xFF) << 24;    
        }  
        public static int byteArrayToInt(byte[] b, int index){  
              return   b[index+3] & 0xFF |    
                      (b[index+2] & 0xFF) << 8 |    
                      (b[index+1] & 0xFF) << 16 |    
                      (b[index+0] & 0xFF) << 24;    
        }  
        
        /**
         * byte[]转int高低位互换
         * @param b
         * @return
         */
        public static int highLowExchangeToInt(byte[] b) {
        	return b[0] & 0xFF | (b[1] & 0xFF) << 8;
        }
        
        /**
         * 将byte数组转int
         * 正常情况下4个byte可以转换成一个int
         * 当数组不足4只需要高位补上就行
         * @param b
         * @return
         */
        public static int byteArrToInt(byte[] b) {  
        	int s =0;
        	if(b.length == 1) {
        		s = b[0] & 0xFF;
        	}else if(b.length == 2) {
        		s = b[1] & 0xFF | (b[0] & 0xFF) << 8 ;
        	}else if(b.length ==3) {
        		s = b[2] & 0xFF | (b[1] & 0xFF) << 8 | (b[0] & 0xFF) << 16 ;
        	}else {
        		s = b[3] & 0xFF | (b[2] & 0xFF) << 8 | (b[1] & 0xFF) << 16 | (b[0] & 0xFF) << 24;  
        	}
            return  s;  
        }  
        
        /** 
         * int转byte[] 
         * @param a 
         * @return 
         */  
        public static byte[] intToByteArray(int a) {    
            return new byte[] {    
                (byte) ((a >> 24) & 0xFF),    
                (byte) ((a >> 16) & 0xFF),       
                (byte) ((a >> 8) & 0xFF),       
                (byte) (a & 0xFF)    
            };    
        }    
        /**  
         * short转byte[] 
         *   
         * @param b  
         * @param s  
         * @param index  
         */    
        public static void byteArrToShort(byte b[], short s, int index) {    
            b[index + 1] = (byte) (s >> 8);    
            b[index + 0] = (byte) (s >> 0);    
        }  
        /**  
         * byte[]转short  
         *   
         * @param b  
         * @param index  
         * @return  
         */    
        public static short byteArrToShort(byte[] b, int index) {    
            return (short) (((b[index + 0] << 8) | b[index + 1] & 0xff));    
        }  
        /**  
         * 16位short转byte[]  
         *   
         * @param s  
         *            short  
         * @return byte[] 
         * */    
        public static byte[] shortToByteArr(short s) {    
            byte[] targets = new byte[2];    
            for (int i = 0; i < 2; i++) {    
                int offset = (targets.length - 1 - i) * 8;    
                targets[i] = (byte) ((s >>> offset) & 0xff);    
            }    
            return targets;    
        }  
        /** 
         * byte[]转16位short 
         * @param b 
         * @return 
         */  
        public static short byteArrToShort(byte[] b){  
            return byteArrToShort(b,0);  
        }  
          
          
        /** 
         * 流转换为byte[] 
         * @param inStream 
         * @return 
         */  
        public static byte[] readInputStream(InputStream inStream) {  
            ByteArrayOutputStream outStream = null;  
            try {  
                outStream = new ByteArrayOutputStream();  
                byte[] buffer = new byte[1024];  
                byte[] data = null;  
                int len = 0;  
                while ((len = inStream.read(buffer)) != -1) {  
                    outStream.write(buffer, 0, len);  
                }  
                data = outStream.toByteArray();  
                return data;  
            }catch (IOException e) {  
                return null;  
            } finally {  
                try {  
                    if (outStream != null) {  
                        outStream.close();  
                    }  
                    if (inStream != null) {  
                        inStream.close();  
                    }  
                } catch (IOException e) {  
                    return null;  
                }  
            }  
        }  
        /** 
         * byte[]转inputstream 
         * @param b 
         * @return 
         */  
        public static InputStream readByteArr(byte[] b){  
            return new ByteArrayInputStream(b);  
        }  
    
    
        /** 
         * 字节数组转16进制字符串 
         * @param b 
         * @return 
         */  
        public static String byteArrToHexString(byte[] b){  
              String result="";  
              for (int i=0; i < b.length; i++) {  
                result += Integer.toString( ( b[i] & 0xff ) + 0x100, 16).substring(1);  
              }  
              return result;  
        }  
          
        /** 
         * 16进制字符创转int 
         * @param hexString 
         * @return 
         */  
        public static int hexStringToInt(String hexString){  
            return Integer.parseInt(hexString,16);  
        }  
        /** 
         * 十进制转二进制 
         * @param i 
         * @return 
         */  
        public static String intToBinary(int i){  
            return Integer.toBinaryString(i);  
        }  
        
    
        /**
         * int转16进制
         * @param b
         * @return
         */
        public static String intToHex16(int b) {
                return String.format("%02x", b);
        }
        
        /**
         * int转hex 长度不够前面补零
         * @param b
         * @param length
         * @return
         */
        public static String intToHexByLength(int b,int byteLength) {
        	int length = byteLength*2;
        	String hex = intToHex16(b);
        	hex = hex.length() <length ? "00"+hex :hex; 
        	return hex;
        }
        
        
        /**
         * 高低位互换高位在后低位前
         * @param dec
         * @return16进制字符串
         */
        public static String decToHex(int dec) {
            String hex = "";
            while(dec != 0) {
                String h = Integer.toString(dec & 0xff, 16);
                if((h.length() & 0x01) == 1)
                    h = '0' + h;
                hex = hex + h;
                dec = dec >> 8;
            }
            hex = hex.length()<4?hex+"00":hex;
            return hex;
        }
    
    	
    	/** 
    	    * @函数功能: 10进制串转为BCD码 
    	    * @输入参数: 10进制串 
    	    * @输出结果: BCD码 
    	    */  
    	public static byte[] str2Bcd(String asc) {  
    	    int len = asc.length();  
    	    int mod = len % 2;  
    	   
    	    if (mod != 0) {  
    	     asc = "0" + asc;  
    	     len = asc.length();  
    	    }  
    	   
    	    byte abt[] = new byte[len];  
    	    if (len >= 2) {  
    	     len = len / 2;  
    	    }  
    	   
    	    byte bbt[] = new byte[len];  
    	    abt = asc.getBytes();  
    	    int j, k;  
    	   
    	    for (int p = 0; p < asc.length()/2; p++) {  
    	     if ( (abt[2 * p] >= '0') && (abt[2 * p] <= '9')) {  
    	      j = abt[2 * p] - '0';  
    	     } else if ( (abt[2 * p] >= 'a') && (abt[2 * p] <= 'z')) {  
    	      j = abt[2 * p] - 'a' + 0x0a;  
    	     } else {  
    	      j = abt[2 * p] - 'A' + 0x0a;  
    	     }  
    	   
    	     if ( (abt[2 * p + 1] >= '0') && (abt[2 * p + 1] <= '9')) {  
    	      k = abt[2 * p + 1] - '0';  
    	     } else if ( (abt[2 * p + 1] >= 'a') && (abt[2 * p + 1] <= 'z')) {  
    	      k = abt[2 * p + 1] - 'a' + 0x0a;  
    	     }else {  
    	      k = abt[2 * p + 1] - 'A' + 0x0a;  
    	     }  
    	   
    	     int a = (j << 4) + k;  
    	     byte b = (byte) a;  
    	     bbt[p] = b;  
    	    }  
    	    return bbt;  
    	}