Spring Data MongoDB 分页查询

在上篇文章 Spring Data MongoDB 环境搭建 基础上进行分页查询

定义公用分页参数类,实现 Pageable 接口

import java.io.Serializable;
import org.springframework.data.domain.Pageable;
import org.springframework.data.domain.Sort;

public class SpringDataPageable implements Serializable, Pageable {
    private static final long serialVersionUID = 1;
    // 当前页
    private Integer pagenumber = 1;
    // 当前页面条数
    private Integer pagesize = 10;
    // 排序条件
    private Sort sort;

    // 当前页面
    @Override
    public int getPageNumber() {
        return getPagenumber();
    }

    // 每一页显示的条数
    @Override
    public int getPageSize() {
        return getPagesize();
    }

    // 第二页所需要增加的数量
    @Override
    public int getOffset() {
        return (getPagenumber() - 1) * getPagesize();
    }

    @Override
    public Sort getSort() {
        return sort;
    }

    public Integer getPagenumber() {
        return pagenumber;
    }

    public void setPagenumber(Integer pagenumber) {
        this.pagenumber = pagenumber;
    }

    public Integer getPagesize() {
        return pagesize;
    }

    public void setPagesize(Integer pagesize) {
        this.pagesize = pagesize;
    }

    public void setSort(Sort sort) {
        this.sort = sort;
    }

    @Override
    public Pageable first() {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public boolean hasPrevious() {
        // TODO Auto-generated method stub
        return false;
    }

    @Override
    public Pageable next() {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public Pageable previousOrFirst() {
        // TODO Auto-generated method stub
        return null;
    }
}

接口 PersonDao

/**
 * 分页查询
 * @param pageNum  开始页
 * @return
 */
public Page paginationQuery(Integer pageNum);

接口实现 PersonDaoImpl

public Page paginationQuery(Integer pageNum) {

    SpringDataPageable pageable = new SpringDataPageable();
    Query query = new Query();
    List orders = new ArrayList();  //排序
    orders.add(new Order(Direction.DESC, "age"));
    Sort sort = new Sort(orders);

    // 开始页
    pageable.setPagenumber(pageNum);
    // 每页条数
    pageable.setPagesize(10);
    // 排序
    pageable.setSort(sort);
    // 查询出一共的条数
    Long count = mongoTemplate.count(query, Person.class);
    // 查询
    List list = mongoTemplate.find(query.with(pageable), Person.class);
    // 将集合与分页结果封装
    Page pagelist = new PageImpl(list, pageable, count);

    return pagelist;
}

测试

/**
 * 分页查询
 */
@Test
public void paginationQuery(){
    Page persons = personDao.paginationQuery(2);
    for(Person p : persons){
        System.out.println(p.getName());
    }
}

作者:itmyhome

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