关于怎样在新框架里如何实现防止同一字段的值重复

拼sql语句查找数据库有没有相同的！用if判断

 

 public void add(PContent pContent) {
  Long panduan = new Long(0);
  String b = pContent.getCname().toString();
  String hql = "select count(*) from Content t where  cname = '" + b + "'";
  panduan = contentDAO.count(hql);
  if (panduan != 0) {

//当前里面有与当前名字重复的
   return;
  }
  Content content = new Content();
  BeanUtils.copyProperties(pContent, content, new String[] { "id" });  //复制
  content.setId(UUID.randomUUID().toString());
  contentDAO.save(content);
 }