初识maven和mybatis,碰见太多的坑!

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  • 这几天学maven和mybatis遇见了很多坑,大部分时间都在百度解决问题,不过现在看来遇见这些坑还是给我很大的感触,至少下次碰见这些坑我不会无力了!记录我初学时完成的第一个成功运行的模块!

实体类

public class Person {
    private int id;
    private String name;
    private int age;
    public Person() {
}
    public Person(int id, String name, int age) {
        this.id = id;
        this.name = name;
        this.age = age;
    }
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    @Override
    public String toString() {
        return "Person{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", age=" + age +
                '}';
    }
}

配置映射文件

 <?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.haiyang.entity.personMapper">
    <select id="queryPersonById" parameterType="int" resultType="com.haiyang.entity.Person">
        select * from person where id = #{id}
    </select>
</mapper>

配件mybatis配置文件

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

<configuration>
    <!--环境配置,连接的数据库-->
    <environments default="development">
        <environment id="development">
            <!--指定事务管理的类型,这里简单使用Java的JDBC的提交和回滚设置-->
            <transactionManager type="JDBC"></transactionManager>
            <!--dataSource 指连接源配置,POOLED是JDBC连接对象的数据源连接池的实现-->
            <dataSource type="POOLED">
                <property name="driver" value="com.microsoft.sqlserver.jdbc.SQLServerDriver"></property>
                <property name="url" value="jdbc:sqlserver://localhost:1433;databaseName=User"></property>
                <property name="username" value="simple"></property>
                <property name="password" value="123456"></property>
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <!--告诉mybatis映射sql语句的路径(注册映射文件)-->
        <mapper resource="personMapper.xml"></mapper>
    </mappers>
</configuration>

测试类

public class test {

    public static void main(String[] args) throws IOException {
        //加载mybatis配置文件(为了访问数据库)
        Reader reader = Resources.getResourceAsReader("conf.xml");
        //主要是导入mybatis配置文件
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);
        //session相当于jdbc中的connection
        SqlSession session = sqlSessionFactory.openSession();
        String statement="com.haiyang.entity.personMapper.queryPersonById";
        Person person=session.selectOne(statement,1);
        System.out.println(person);
        session.close();
    }
}

pom.xml配置

<?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>org.example</groupId>
    <artifactId>MybatisDemo</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.2.3</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.12</version>
        </dependency>
    </dependencies>
</project>

不知道怎么回事我maven就是导不了sql驱动包,但是我本地仓库已经有了驱动的gav就是不知道为什么导不了,主要是在乡下没有WiFi,下次有WiFi一定要卸载sqlserver下一个MySQL

看下我第一个成功的项目文件

运行结果

希望可以让初学者避免和我一样不会搞的尴尬 0.0

  • 如果有错误,欢迎指正