小编use*_*577的帖子

任何人都可以解释我下面的场景
代码测试
UserTransaction.java

@Override
public ServiceResponse<User> get(String name) {
    ServiceResponse<User> response = new ServiceResponse<User>();
    List<Map<String, Object>> exp = new ArrayList<Map<String, Object>>();
    Map<String, Object> map = new HashMap<String, Object>();
    map.put("expression", "eq");
    map.put("property", "name");
    map.put("value", name);
    exp.add(map);
    List<User> users = userDao.getByCriteria(exp);
    if (!users.isEmpty()) {
        response.setResponse(users.get(0));
    } else {
        response.setResponse(null);
    }
    return response;
}   

UserDao.java

public List<User> getByCriteria(List<Map<String, Object>> exp) {
  DetachedCriteria criteria = DetachedCriteria.forClass(User.class);
  for (Integer i=0;i<exp.size();i++){
    String expression = (String) exp.get(i).get("expression");
    String property = (String) exp.get(i).get("property");
    if(expression.equals("eq"){
       criteria.add(Restrictions.eq(property,exp.get(i).get("value")));
    }
  }
  return …