Spring - 用于 QueryDsl 支持的高级比较器

使用Spring框架可以方便地支持QueryDsl的高级比较器，这为开发人员提供了更多的查询灵活性和便利性。QueryDsl是一个用于构建类型安全的动态查询的框架，它提供了一种更直观、更优雅的方式来构建数据库查询。

xml
  com.querydsl
  querydsl-core
  ${querydsl.version}
  com.querydsl
  querydsl-jpa
  ${querydsl.version}
  com.querydsl
  querydsl-apt
  ${querydsl.version}
  provided

java
@Entity
@QueryEntity
public class User {
  @Id
  private Long id;
  
  private String name;
  
  private Integer age;
  
  // 省略getter和setter方法
}

java
QUser user = QUser.user;
Predicate predicate = user.age.goe(18);
List userList = userRepository.findAll(predicate);

java
@Entity
@QueryEntity
public class User {
  @Id
  private Long id;
  
  private String name;
  
  private Integer age;
  
  // 省略getter和setter方法
}
@Repository
public interface UserRepository extends JpaRepository, QuerydslPredicateExecutor {
}
@Service
public class UserService {
  @Autowired
  private UserRepository userRepository;
  public List findAdultUsers() {
    QUser user = QUser.user;
    Predicate predicate = user.age.goe(18);
    
    return userRepository.findAll(predicate);
  }
}
@Controller
public class UserController {
  @Autowired
  private UserService userService;
  @GetMapping("/users/adult")
  public String getAdultUsers(Model model) {
    List userList = userService.findAdultUsers();
    model.addAttribute("users", userList);
    
    return "adult-users";
  }
}