使用Mybatis实现基本的增删改查------数据输入

创建一个空的Maven项目,删去src,用作存储pom的父项目

pom中存放下列依赖:

    <dependencies><dependency><groupId>org.mybatis</groupId><artifactId>mybatis</artifactId><version>3.5.11</version></dependency><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>5.1.46</version></dependency></dependencies>

创建Module在pom中加入测试依赖

    <dependencies><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>4.13.2</version><scope>test</scope></dependency></dependencies>

创建数据库

CREATE TABLE student(
stuID INTEGER NOT NULL,
stuName VARCHAR(20),
stuSalary DECIMAL(10,3) 
)

创建实体类

package su.Entity;/*** @author haustsusu* @create 2023-09-08-19:12*/
public class Student {private Integer stuId;private String stuName;private Double stuSalary;public Student() {}public Student(Integer stuId, String stuName, Double stuSalary) {this.stuId = stuId;this.stuName = stuName;this.stuSalary = stuSalary;}public Integer getStuId() {return stuId;}public void setStuId(Integer stuId) {this.stuId = stuId;}public String getStuName() {return stuName;}public void setStuName(String stuName) {this.stuName = stuName;}public Double getStuSalary() {return stuSalary;}public void setStuSalary(Double stuSalary) {this.stuSalary = stuSalary;}@Overridepublic String toString() {return "Student{" +"stuId=" + stuId +", stuName='" + stuName + '\'' +", stuSalary=" + stuSalary +'}';}
}

创建Mybatis框架需要创建Mapper.xml,Mapper接口,MybatisConfig配置文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configurationPUBLIC "-//mybatis.org//DTD Config 3.0//EN""https://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration><!--    引入jdbc.properties--><properties resource="jdbc.properties"></properties><settings><setting name="logImpl" value="STDOUT_LOGGING"/></settings><environments default="development">
<!--        表示配置Mybatis的一个具体环境--><environment id="development">
<!--            mybatis内置的事务管理器--><transactionManager type="JDBC"/>
<!--            配置数据源--><dataSource type="POOLED"><property name="driver" value="${jdbc.driver}"/><property name="url" value="${jdbc.url}"/><property name="username" value="${jdbc.username}"/><property name="password" value="${jdbc.password}"/></dataSource></environment></environments><!--     而 mappers 标签就是用来配置需要加载的 sql 映射配置文件路径的--><mappers><mapper resource="StudentMapper.xml"/></mappers>
</configuration>

Mapper接口

public interface stuMapper {List<Student> QueryStudents();Student QueryStudent(Integer Id);}

Mybatis配置文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configurationPUBLIC "-//mybatis.org//DTD Config 3.0//EN""https://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration><!--    引入jdbc.properties--><properties resource="jdbc.properties"></properties><settings><setting name="logImpl" value="STDOUT_LOGGING"/></settings><environments default="development">
<!--        表示配置Mybatis的一个具体环境--><environment id="development">
<!--            mybatis内置的事务管理器--><transactionManager type="JDBC"/>
<!--            配置数据源--><dataSource type="POOLED"><property name="driver" value="${jdbc.driver}"/><property name="url" value="${jdbc.url}"/><property name="username" value="${jdbc.username}"/><property name="password" value="${jdbc.password}"/></dataSource></environment></environments><!--     而 mappers 标签就是用来配置需要加载的 sql 映射配置文件路径的--><mappers><mapper resource="StudentMapper.xml"/></mappers>
</configuration>

最后在测试类中运行

public class StudentTest {@Testpublic void test01() throws IOException {//1.读取外部配置文件,获取一个输入流InputStream resourceAsStream = Resources.getResourceAsStream("MybatisConfig.xml");//2.创建sqlSessionFactory对象SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream);//3.获取Sqlsession对象[自动开启JDBC]SqlSession sqlSession = sqlSessionFactory.openSession();//4.获取代理mapper对象stuMapper mapper = sqlSession.getMapper(stuMapper.class);//执行查询所有学生的方法List<Student> students = (List<Student>) mapper.QueryStudents();//查询id学生的方法Student student = mapper.QueryStudent(10001);System.out.println("某个学生--------------------");System.out.println(student);System.out.println("某个学生--------------------");for (Student s:students){System.out.println(s);}//5.管理资源与提交事务sqlSession.close();}
}

结果:

E:\Java\jdk1.8.0_301\bin\java.exe -ea -Didea.test.cyclic.buffer.size=1048576 "-javaagent:E:\IDEA\idea\IntelliJ IDEA 2020.1\lib\idea_rt.jar=8837:E:\IDEA\idea\IntelliJ IDEA 2020.1\bin" -Dfile.encoding=UTF-8 -classpath "E:\IDEA\idea\IntelliJ IDEA 2020.1\lib\idea_rt.jar;E:\IDEA\idea\IntelliJ IDEA 2020.1\plugins\junit\lib\junit5-rt.jar;E:\IDEA\idea\IntelliJ IDEA 2020.1\plugins\junit\lib\junit-rt.jar;E:\java\jdk1.8.0_301\jre\lib\charsets.jar;E:\java\jdk1.8.0_301\jre\lib\deploy.jar;E:\java\jdk1.8.0_301\jre\lib\ext\access-bridge-64.jar;E:\java\jdk1.8.0_301\jre\lib\ext\cldrdata.jar;E:\java\jdk1.8.0_301\jre\lib\ext\dnsns.jar;E:\java\jdk1.8.0_301\jre\lib\ext\jaccess.jar;E:\java\jdk1.8.0_301\jre\lib\ext\jfxrt.jar;E:\java\jdk1.8.0_301\jre\lib\ext\localedata.jar;E:\java\jdk1.8.0_301\jre\lib\ext\nashorn.jar;E:\java\jdk1.8.0_301\jre\lib\ext\sunec.jar;E:\java\jdk1.8.0_301\jre\lib\ext\sunjce_provider.jar;E:\java\jdk1.8.0_301\jre\lib\ext\sunmscapi.jar;E:\java\jdk1.8.0_301\jre\lib\ext\sunpkcs11.jar;E:\java\jdk1.8.0_301\jre\lib\ext\zipfs.jar;E:\java\jdk1.8.0_301\jre\lib\javaws.jar;E:\java\jdk1.8.0_301\jre\lib\jce.jar;E:\java\jdk1.8.0_301\jre\lib\jfr.jar;E:\java\jdk1.8.0_301\jre\lib\jfxswt.jar;E:\java\jdk1.8.0_301\jre\lib\jsse.jar;E:\java\jdk1.8.0_301\jre\lib\management-agent.jar;E:\java\jdk1.8.0_301\jre\lib\plugin.jar;E:\java\jdk1.8.0_301\jre\lib\resources.jar;E:\java\jdk1.8.0_301\jre\lib\rt.jar;D:\SSM_MybatisOne\SSM_Mybatis_Student\target\test-classes;D:\SSM_MybatisOne\SSM_Mybatis_Student\target\classes;C:\Users\小苏\.m2\repository\junit\junit\4.13.2\junit-4.13.2.jar;C:\Users\小苏\.m2\repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar;C:\Users\小苏\.m2\repository\org\mybatis\mybatis\3.5.11\mybatis-3.5.11.jar;C:\Users\小苏\.m2\repository\mysql\mysql-connector-java\5.1.46\mysql-connector-java-5.1.46.jar" com.intellij.rt.junit.JUnitStarter -ideVersion5 -junit4 StudentCRUDTest.StudentTest,test01
Logging initialized using 'class org.apache.ibatis.logging.stdout.StdOutImpl' adapter.
PooledDataSource forcefully closed/removed all connections.
PooledDataSource forcefully closed/removed all connections.
PooledDataSource forcefully closed/removed all connections.
PooledDataSource forcefully closed/removed all connections.
Opening JDBC Connection
Created connection 1909546776.
Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@71d15f18]
==>  Preparing: select stuID stuId,stuName stuName,stuSalary stuSalary from student
==> Parameters: 
<==    Columns: stuId, stuName, stuSalary
<==        Row: 10001, 苏宝全, 2000.365
<==        Row: 10002, 苏风严, 3000.451
<==      Total: 2
==>  Preparing: select stuID stuId,stuName stuName,stuSalary stuSalary from student where stuId=?
==> Parameters: 10001(Integer)
<==    Columns: stuId, stuName, stuSalary
<==        Row: 10001, 苏宝全, 2000.365
<==      Total: 1
某个学生--------------------
Student{stuId=10001, stuName='苏宝全', stuSalary=2000.365}
某个学生--------------------
Student{stuId=10001, stuName='苏宝全', stuSalary=2000.365}
Student{stuId=10002, stuName='苏风严', stuSalary=3000.451}
Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@71d15f18]
Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@71d15f18]
Returned connection 1909546776 to pool.Process finished with exit code 0

场景一:传入单个数据:(数据名可以随意写,但不建议)