mybatis-plus分页设置无效解决方法

mybatis-plus自带分页功能，这样可以省去很多麻烦，也不用再去引入其他jar包。

IPage分页的使用

@Override
    public IPage<User> getLimit() {
    // 参数一:当前页面 currentPage  参数二：每页展示数 pageSize
        Page<User> page = new Page<>(1, 3);
        QueryWrapper<User> wrapper = new QueryWrapper<>();
        wrapper.like("realname", "高");
        IPage<User> userIPage = userMapper.selectPage(page, wrapper);
        return userIPage;
    }

如上代码一顿操作后，结果发现并没有分页成功。
这是因为我们缺少了PaginationInterceptor的配置。

单数据源下PaginationInterceptor的配置

package com.gyt.demo.common.config;

import com.baomidou.mybatisplus.extension.plugins.PaginationInterceptor;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * @author gaoyuntao
 * @date 2020/12/24 15:35
 **/
@Configuration
@ConditionalOnClass(value = {PaginationInterceptor.class})
public class MyBatisPlusPageConfig {
    @Bean
    public PaginationInterceptor paginationInterceptor() {
        return new PaginationInterceptor();
    }
}

新建一个MyBatisPlusPageConfig类，简单配置完后就可以了。

多数据源下PaginationInterceptor的配置

如果你的项目是存在多个数据源，这里提供一种配置方式，以供参考：

package com.gyt.demo.common.config;

import com.baomidou.mybatisplus.annotation.DbType;
import com.baomidou.mybatisplus.extension.plugins.PaginationInterceptor;
import com.baomidou.mybatisplus.extension.plugins.pagination.optimize.JsqlParserCountOptimize;
import com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean;
import org.apache.ibatis.plugin.Interceptor;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;

import javax.sql.DataSource;

/**
 * @author gaoyuntao
 * @date 2020/10/10 14:10
 **/
@Configuration
@MapperScan(basePackages = "com.gyt.demo.mapper.db1"
        ,sqlSessionTemplateRef = "SqlSessionTemplate"
        ,sqlSessionFactoryRef = "SqlSessionFactory")
public class DataSourceConf {

    @Bean(name = "DataSource")
    @Primary
    @ConfigurationProperties(prefix = "spring.datasource.db1")
    public DataSource DataSource(){
        return DataSourceBuilder.create().build();
    }
    @Bean("SqlSessionFactory")
    @Primary
    public SqlSessionFactory SqlSessionFactory() throws Exception {
        // 一般情况下使用SqlSessionFactotyBean 即可（包括使用mybatis-generator)
//        SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
        // 当使用myBatis-plus的时候需要使用 MybatisSqlSessionFactoryBean
        MybatisSqlSessionFactoryBean sqlSessionFactoryBean = new MybatisSqlSessionFactoryBean();
        sqlSessionFactoryBean.setDataSource(DataSource());
        sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mapper/db1/*.xml"));
        // Mybatis-plus 分页查询设置
        Interceptor[] plugins = new Interceptor[1];
        plugins[0] = MpPaginationInterceptor();
        sqlSessionFactoryBean.setPlugins(plugins);
        return sqlSessionFactoryBean.getObject();
    }
    @Bean(name ="TxMananger")
    @Primary
    public DataSourceTransactionManager TxMananger() {
        return new DataSourceTransactionManagerDataSource());
    }

    @Bean(name ="SqlSessionTemplate")
    @Primary
    public SqlSessionTemplate SqlSessionTemplate() throws Exception {
        return new SqlSessionTemplate(SqlSessionFactory());
    }

    /*
        myBatis-plus 分页查询配置
         */
    @Bean(name="MpPaginationInterceptor")
    public PaginationInterceptor MpPaginationInterceptor() {
        PaginationInterceptor paginationInterceptor = new PaginationInterceptor();
        paginationInterceptor.setLimit(300);
        paginationInterceptor.setDialectType(DbType.MYSQL.getDb());
        paginationInterceptor.setCountSqlParser(new JsqlParserCountOptimize(true));
        return paginationInterceptor;
    }
}

如上代码，自定义一个PaginationInterceptor的Bean，并插入到SqlSessionFactory 中即可。

关于MyBatis-plus多数据源配置请移步：https://blog.csdn.net/Mr_going/article/details/111590622