对象属性选择性拷贝 JAVA生成密码随机数

org.springframework.beans.BeanUtils.copyProperties(source, target,new String[]{'userId',  'modifyBy', 'modifyAt'}) 







StringBuffer sb = new StringBuffer();

 String str = '0123456789';

 Random r = new Random();

 for(int i=0;i

       int num = r.nextInt(str.length());

       sb.append(str.charAt(num));

       str = str.replace((str.charAt(num)+''), '');

 }

 return sb.toString();