jpa之PagingAndSortingRepository带分页查询

此篇文章建立在spring整合jpa环境的基础上,不会的请看前几篇文章.

1.1.  Dao接口继承PagingAndSortingRepository接口

PersonDao.java

package com.morris.dao.inter; import org.springframework.data.repository.PagingAndSortingRepository; import com.morris.entity.Person; public interface PersonDao extends PagingAndSortingRepository{ }

1.2.  使用PagingAndSortingRepository接口的方法

1.2.1.  新增

public void save(Person person) {
 
       personDao.save(person);
    }

1.2.2.  删除

public void delete(Person person) {
       personDao.delete(person);
      
    }
 
    public void delete(Integer id) {
       personDao.delete(id);
    }

1.2.3.  修改

public void update(Person person) {
       personDao.save(person); 
    }

1.2.4.  查询

public Person findById(Integer id) {
 
       Person person = personDao.findOne(id);
       return person;
    }
 
    public Iterable findAll() {
 
       Iterable persons = personDao.findAll();
       return persons;
    }

1.2.5.  分页查询

public Iterable findAll(Pageable pageable) {
       Page persons = personDao.findAll(pageable);
       return persons;
    }

其中Pageable是一个接口,具体的实现类为PageRequest,下面为PageRequest的一个构造方法

public PageRequest(int page, int size) { this(page, size, null); }

只需要指定分页时页数和每页的大小即可.

1.3.  源代码

IPersonService

package com.morris.service.inter; import org.springframework.data.domain.Pageable; import com.morris.entity.Person; public interface IPersonService { void save(Person person); void delete(Person person); void delete(Integer id); void update(Person person); Person findById(Integer id); Iterable findAll(); Iterable findAll(Pageable pageable); }

PersonServiceImpl.java

package com.morris.service.impl; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.data.domain.Page; import org.springframework.data.domain.Pageable; import org.springframework.stereotype.Service; import com.morris.dao.inter.PersonDao; import com.morris.entity.Person; import com.morris.service.inter.IPersonService; @Service("personService") public class PersonServiceImpl implements IPersonService { @Autowired private PersonDao personDao; public void save(Person person) { personDao.save(person); } public void delete(Person person) { personDao.delete(person); } public void delete(Integer id) { personDao.delete(id); } public void update(Person person) { personDao.save(person); } public Person findById(Integer id) { Person person = personDao.findOne(id); return person; } public Iterable findAll() { Iterable persons = personDao.findAll(); return persons; } public Iterable findAll(Pageable pageable) { Page persons = personDao.findAll(pageable); return persons; } }