加入收藏 | 设为首页 | 会员中心 | 我要投稿 李大同 (https://www.lidatong.com.cn/)- 科技、建站、经验、云计算、5G、大数据,站长网!
当前位置: 首页 > 大数据 > 正文

mybatis扩展之使用PageHelper插件进行分页(是真好用)

发布时间:2020-12-14 18:02:25 所属栏目:大数据 来源:网络整理
导读:首先引入相关的jar包: 然后是在Mybatis全局配置文件中配置: plugins plugin interceptor ="com.github.pagehelper.PageInterceptor" / plugin / 就可以使用了。 EmployeeMapper.java中 public ListEmployee getAllEmp(); EmployeeMapper.xml中 select id =

首先引入相关的jar包:

然后是在Mybatis全局配置文件中配置:

    <plugins>
        plugin interceptor="com.github.pagehelper.PageInterceptor"></plugin>
    </>

就可以使用了。

EmployeeMapper.java中

    public List<Employee> getAllEmp();

EmployeeMapper.xml中

    select id="getAllEmp" resultType="com.gong.mybatis.bean.Employee">
        select * from tbl_employee
    select>

进行测试:首先是不带分页的测试

package com.gong.mybatis.test;

import java.io.IOException;
 java.io.InputStream;
 java.util.ArrayList;
 java.util.Arrays;
 java.util.HashMap;
 java.util.List;
 java.util.Map;

 org.apache.ibatis.io.Resources;
 org.apache.ibatis.session.SqlSession;
 org.apache.ibatis.session.SqlSessionFactory;
 org.apache.ibatis.session.SqlSessionFactoryBuilder;
 org.junit.Test;

 com.github.pagehelper.Page;
 com.github.pagehelper.PageHelper;
 com.github.pagehelper.PageInfo;
 com.gong.mybatis.bean.Department;
 com.gong.mybatis.bean.Employee;
 com.gong.mybatis.dao.EmployeeMapper;
 com.gong.mybatis.mapper.EmployeeMapperDynamicSql;

public class TestMybatis5 {
    
    public SqlSessionFactory getSqlSessionFactory() throws IOException {
        String resource = "mybatis-config.xml";
        InputStream is = Resources.getResourceAsStream(resource);
        return new SqlSessionFactoryBuilder().build(is);
    }

    @Test
    void test()  IOException {
        SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
        SqlSession openSession = sqlSessionFactory.openSession();
        
        try {
            EmployeeMapper mapper = openSession.getMapper(EmployeeMapper.);
            List<Employee> emps = mapper.getAllEmp();
            for(Employee emp:emps) {
                System.out.println(emp);
            }

        } finally {
            // TODO: handle finally clause
            openSession.close();
        }
    }
    
}

输出:

DEBUG 01-23 14:29:17,295 ==>  Preparing: select * from tbl_employee   (BaseJdbcLogger.java:145) 
DEBUG 01-23 14:29:17,334 ==> Parameters:   (BaseJdbcLogger.java:145) 
DEBUG 01-23 14:29:17,412 ==      Total: 7  (BaseJdbcLogger.java:145) 
Employee [id=1,lastName=dema,1)">genderemail=dema@qq.com,1)">dept=null]
Employee [id=2,1)">=jack,1)">=675544321@qq.com,1)">=3,1)">=小红,1)">=0,1)">=xiaohong@qq.com,1)">=4,1)">=小明,1)">=xiaoming@qq.com,1)">=6,1)">=timo,1)">=timo@qq.com,1)">=7,1)">=manwang,1)">=manwang@qq.com,1)">=8,1)">=null]

我们共有7条数据。

第一种分页方式:

);
            第一个参数为当前页码,第二个参数是每页的记录数
            Page<Object> page = PageHelper.startPage(1,5);
            List<Employee> emps =(Employee emp:emps) {
                System.out.println(emp);
            }
            System.out.println("当前页码:"+page.getPageNum());
            System.out.println("总记录数:"+page.getTotal());
            System.out.println("每页几条记录:"+page.getPageSize());
            System.out.println("总页码数:"+page.getPages());
        }             openSession.close();
        }
    }
}

输出:

DEBUG 01-23 14:32:50,024 Cache Hit Ratio [SQL_CACHE]: 0.0  (LoggingCache.java:62) 
DEBUG 01-23 14:32:50,071 ==>  Preparing: SELECT count(0) FROM tbl_employee   (BaseJdbcLogger.java:145) 
DEBUG 01-23 14:32:50,128 ==> Parameters:   (BaseJdbcLogger.java:145) 
DEBUG 01-23 14:32:50,197 1  (BaseJdbcLogger.java:145) 
DEBUG 01-23 14:32:50,199 ==>  Preparing: select * from tbl_employee LIMIT 5   (BaseJdbcLogger.java:145) 
DEBUG 01-23 14:32:50,1)">==> Parameters:   (BaseJdbcLogger.java:145) 
DEBUG 01-23 14:32:50,212 <==      Total: 5  (BaseJdbcLogger.java:145) 
Employee [id当前页码:1
总记录数:7
每页几条记录:5
总页码数:2

第二种分页方式:

在上一种设置起始页和每页记录的情况下继续增加:

第一个参数为当前页码,第二个参数是每页的记录数
            Page<Object> page = PageHelper.startPage(1,2第一个参数为传入的数据,第二个参数为连续显示多少页
            PageInfo<Employee> pageInfo = new PageInfo<>(emps,3(Employee emp:emps) {
                System.out.println(emp);
            }
            System.out.println("当前页码:"+pageInfo.getPageNum());
            System.out.println("总记录数:"+pageInfo.getTotal());
            System.out.println("每页几条记录:"+pageInfo.getPageSize());
            System.out.println("总页码数:"+pageInfo.getPages());
            System.out.println("是否第一页:"+pageInfo.isIsFirstPage());
            System.out.println("是否最后一页:"+pageInfo.isIsLastPage());
            System.out.println("连续显示的页码:"int[] navigatepageNums = pageInfo.getNavigatepageNums();
            for (int i = 0; i < navigatepageNums.length; i++) {
                System.out.println(navigatepageNums[i]);
            }
        } DEBUG 01-23 14:39:20,125 Cache Hit Ratio [SQL_CACHE]: 0.0  (LoggingCache.java:62) 
DEBUG 01-23 14:39:20,172 ==>  Preparing: SELECT count(0) FROM tbl_employee   (BaseJdbcLogger.java:145) 
DEBUG 01-23 14:39:20,247 ==> Parameters:   (BaseJdbcLogger.java:145) 
DEBUG 01-23 14:39:20,278 1  (BaseJdbcLogger.java:145) 
DEBUG 01-23 14:39:20,281 Preparing: select * from tbl_employee LIMIT 2   (BaseJdbcLogger.java:145) 
DEBUG 01-23 14:39:20,283 Parameters:   (BaseJdbcLogger.java:145) 
DEBUG 01-23 14:39:20,292 <Total: 2  (BaseJdbcLogger.java:145) 
Employee [id当前页码:1
总记录数:7
每页几条记录:2
总页码数:4
是否第一页:true
是否最后一页:false
连续显示的页码:
1
2
3

(编辑:李大同)

【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容!

    推荐文章
      热点阅读