表person对应的model类：

@Entity
@Table(name = "person")
public class Person {
    @Id
    @GeneratedValue
    private Long id;
    private Integer age;
    private String name;
    @Column(name = "nick_name")
    private String nickName;
    private String company;
    private Date birthday;
    
    // getter and setter
}

public interface PersonRepository extends JpaRepository<Person, Long>, JpaSpecificationExecutor<Person> {
}

查询如果姓名不为空则按照姓名倒序先排序，然后按照生日升序排序，分页大小15。

public Page<Person> findAll(SearchRequest request) {
    Specification<Person> specification = new Specifications<Person>()
            .eq(StringUtils.isNotBlank(request.getName()), "name", request.getName())
            .gt("age", 18)
            .between("birthday", new Range<>(new Date(), new Date()))
            .like("nickName", "%og%")
            .build();
            
    Sort sort = new Sorts()
        .desc(StringUtils.isNotBlank(request.getName()), "name")
        .asc("birthday")
        .build();
            
    return personRepository.findAll(specification, new PageRequest(0, 15, sort));
}