在使用Mybatisplus时报错Invalid bound statement (not found)，在此记录一下

先附上解决办法

step 1、启动类加上@MapperScan注解

package com.study.test;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@MapperScan(basePackages = {"com.study.*.dao","com.study.*.mapper"})
@SpringBootApplication
public class UaaMain {
    public static void main(String[] args) {
            SpringApplication.run(UaaMain.class, args);
        }
}

step 2、
pom.xml配置中指定resource资源路径

	<build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <filtering>false</filtering>
                <includes>
                    <include>**/*.xml</include>
                </includes>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
                <filtering>false</filtering>
                <includes>
                    <include>**/*</include>
                </includes>
            </resource>
        </resources>
    </build>

情景复现

@MapperScan ---- 用于扫描指定路径下的Mapper文件

package com.study.test;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@MapperScan(basePackages = {"com.study.*.dao","com.study.*.mapper"})
@SpringBootApplication
public class UaaMain {
    public static void main(String[] args) {
            SpringApplication.run(UaaMain.class, args);
        }
}

使用@MapperScan注解后会扫描 com.study.*.dao 和 com.study.*.mapper 路径下所有mapper文件，这样就不需要再每个mapper接口上加@Mapper注解标识了

在mapper中自定义方法

package com.study.test.dao;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.study.test.entity.SysUser;
import org.apache.ibatis.annotations.Param;

public interface UserMapper extends BaseMapper<SysUser> {
	SysUser getByUserId(@Param("id") Long id);
}

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >

<mapper namespace="com.study.test.dao.UserMapper">

    <resultMap id="base" type="com.study.test.entity.SysUser">
        <result property="id" column="id"/>
        <result property="password" column="password"/>
        <result property="username" column="username"/>
        <result property="code" column="code" />
        <result property="age" column="age" />
        <result property="roleId" column="rid" />
    </resultMap>
    
    <select id="getByUserId" resultMap="base" resultType="com.study.test.entity.SysUser">
        select * from user where id = #{id}
    </select>

</mapper>

使用UserMapper 里继承自 BaseMapper 里的方法没有问题
使用UserMapper 里的自定义的 getByUserId 方法时报错Invalid bound statement (not found)

这里看到xml中namespace也映射到了对应的mapper
select语句中的id也映射到了mapper中对应的方法名

查看target中编译打包的文件

发现只有Mapper文件，并没有xml文件

这是因为maven打包时默认路径扫描是在src/main/resources路径下
这里将xml文件放在了src/main/java路径下
需要在pom.xml文件中对maven扫描资源路径做一个配置

	<build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <filtering>false</filtering>
                <includes>
                    <include>**/*.xml</include>
                </includes>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
                <filtering>false</filtering>
                <includes>
                    <include>**/*</include>
                </includes>
            </resource>
        </resources>
    </build>

重新maven clean再maven install发现xml文件打包进去了

再执行上面UserMapper中的getByUserId方法正常