java中添加流水单号

//用于生成出库的ID
      public static String getexportid(){
    //生成规则：Ck+时间戳(20170626143520)+6位的随机数
          return "CK"+getnowstr()+getStringRandom(6);
      }
      public static String getstorageid(){
            //生成规则：Rk+时间戳(20170626143520)+6位的随机数
                  return "RK"+getnowstr()+getStringRandom(8);
              }
      
      private static String getnowstr(){
          Date date = new Date();
          SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
          String str = sdf.format(date);
          return str;
      }
      //随机生成六位数
      private static String getStringRandom(int length) {  
          
          String val = "";  
          Random random = new Random();  
            
          //参数length，表示生成几位随机数  
          for(int i = 0; i < length; i++) {  
                
              String charOrNum = random.nextInt(2) % 2 == 0 ? "char" : "num";  
              //输出字母还是数字  
              if( "char".equalsIgnoreCase(charOrNum) ) {  
                  //输出是大写字母还是小写字母  
                  int temp = random.nextInt(2) % 2 == 0 ? 65 : 97;  
                  val += (char)(random.nextInt(26) + temp);  
              } else if( "num".equalsIgnoreCase(charOrNum) ) {  
                  val += String.valueOf(random.nextInt(10));  
              }  
          }  
          return val;  
      }