这个工程不知道哪里出错了，自己排查不出来，麻烦老师排查解惑

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.imooc</groupId>
    <artifactId>HomeworkSong</artifactId>
    <packaging>pom</packaging>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>

    <repositories>
        <repository>
            <id>aliyun</id>
            <name>aliyun</name>
            <url>https://maven.aliyun.com/repository/public</url>
        </repository>
    </repositories>

    <dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.1</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-classic</artifactId>
            <version>1.2.3</version>
        </dependency>
    </dependencies>

</project>

mybatis-config.xml

<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<settings>
<setting name="mapUnderscoreToCamelCase" value="true"/>
</settings>

<environments default="dev">
<environment id="dev">
<transactionManager type="JDBC"></transactionManager>
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/homeworksong?useUnicode=true&amp;characterEncoding=UTF-8"/>
<property name="user" value="root"/>
<property name="password" value="154672"/>
</dataSource>
</environment>
</environments>
<mappers>
<package name="com.imooc.dao"/>
</mappers>

</configuration>

logback.xml

<?xml version="1.0" encoding="UTF-8" ?>
<configuration>
    <appender name="console" class="ch.qos.logback.core.ConsoleAppender">
        <encoder>
            <pattern>[%thread] %d{HH:mm:ss.SSS} %-5level %logger{36} - %msg%n</pattern>
        </encoder>
    </appender>
    <root level="debug">
        <appender-ref ref="console"/>
    </root>
</configuration>

MyBatisUtils

package com.imooc.utils;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import java.io.Reader;

public class MyBatisUtils {
    private static SqlSessionFactory sqlSessionFactory=null;
    static {
        try{
            Reader reader= Resources.getResourceAsReader("mybatis-config.xml");
            sqlSessionFactory=new SqlSessionFactoryBuilder().build(reader);
        }catch (Exception e){
            e.printStackTrace();
            throw new ExceptionInInitializerError();
        }
    }

    public static SqlSession openSession(){
        return sqlSessionFactory.openSession();
    }

    public static void closeSession(SqlSession session){
        if(session!=null){
            session.close();
        }
    }
}

实体类Song

package com.imooc.entity;

import java.util.Date;

public class Song {
    private Integer id;
    private String name;
    private String singer;
    private String category;
    private String writer;
    private String language;
    private Date issudate;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getSinger() {
        return singer;
    }

    public void setSinger(String singer) {
        this.singer = singer;
    }

    public String getCategory() {
        return category;
    }

    public void setCategory(String category) {
        this.category = category;
    }

    public String getWriter() {
        return writer;
    }

    public void setWriter(String writer) {
        this.writer = writer;
    }

    public String getLanguage() {
        return language;
    }

    public void setLanguage(String language) {
        this.language = language;
    }

    public Date getIssudate() {
        return issudate;
    }

    public void setIssudate(Date issudate) {
        this.issudate = issudate;
    }

    @Override
    public String toString() {
        return "Song{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", singer='" + singer + '\'' +
                ", category='" + category + '\'' +
                ", writer='" + writer + '\'' +
                ", language='" + language + '\'' +
                ", issudate=" + issudate +
                '}';
    }
}

dao接口SongDAO

package com.imooc.dao;

import com.imooc.entity.Song;
import org.apache.ibatis.annotations.Select;

import java.util.List;

public interface SongDAO {
    @Select("select * from t_song")
    public List<Song> selectAllSong();

}

测试类testSong

import com.imooc.dao.SongDAO;
import com.imooc.entity.Song;
import com.imooc.utils.MyBatisUtils;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;

import java.util.List;

public class testSong {
    @Test
    public void testSelectAllSong(){
        SqlSession session=null;
        try{
            session= MyBatisUtils.openSession();
            SongDAO songDAO=session.getMapper(SongDAO.class);
            List<Song> list=songDAO.selectAllSong();
            for(Song s:list){
                System.out.println(s);
            }
            session.commit();
        }catch(Exception e){
            e.printStackTrace();
            if(session!=null){
                session.rollback();
            }
        }finally {
            MyBatisUtils.closeSession(session);
        }
    }
}

报错提示：

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