java框架學習——Mybatis的註解開發實現CRUD操作

Mybatis的註解開發

一環境搭建

1.創建新工程命名ArtifactId爲：AnnotationStudentMybatis並且在pom.xml中添加依賴
添加依賴代碼如下：

<?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.lut</groupId>
    <artifactId>AnnotationStudentMybatis</artifactId>
    <version>1.0-SNAPSHOT</version>
    
    <dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.5</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.20</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

</project>

2.在src-》main-》java包下新建javaclass命名分別爲：com.lut.domain.Student和com.lut.dao.IStudentDao
①在Student.class中編寫代碼屬性和getter、setter及toString()方法
具體代碼如下：

package com.lut.domain;
import java.io.Serializable;
/**
 * @author Roy
 * @date 2020/6/27 16:16
 */
public class Student implements Serializable {
    private Integer id;
    private String stuName;
    private String Major;
    private String sex;
    private Integer age;
    @Override
    public String toString() {
        return "Student{" +
                "id=" + id +
                ", stuName='" + stuName + '\'' +
                ", Major='" + Major + '\'' +
                ", sex='" + sex + '\'' +
                ", age=" + age +
                '}';
    }
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
   public String getStuName() {
        return stuName;
    }
    public void setStuName(String stuName) {
        this.stuName = stuName;
    }
    public String getMajor() {
        return Major;
    }
    public void setMajor(String major) {
        Major = major;
    }
    public String getSex() {
        return sex;
    }
    public void setSex(String sex) {
        this.sex = sex;
    }
    public Integer getAge() {
        return age;
    }
    public void setAge(Integer age) {
        this.age = age;
    }
}

3.在Resources包下新建jdbc.properties和sqlMapConfig.xml配置文件
①其中jdbc.properties中數據庫配置如下：

jdbc.driver=com.mysql.cj.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/mybatis
jdbc.username=root
jdbc.password=123456

②其中sqlMapConfig.xml配置文件如下：

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.ory//DTD Config 3.0//EN"
        "htpp://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <!--引入外部配置文件-->
    <properties resource="jdbcConfig.properties"></properties>
    <!--配置別名-->
    <typeAliases>
        <package name="com.lut.domain"></package>
    </typeAliases>
    <!--配置環境-->
    <environments default="mysql">
        <environment id="mysql">
            <transactionManager type="JDBC"></transactionManager>
            <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>
    <!--引入指定帶有註解的dao接口所在的位置-->
    <mappers>
        <package name="com.lut.dao"></package>
    </mappers>
</configuration>

二.使用註解寫入具體方法並測試

1.在IStudentDao.java中寫入具體代碼如下：

package com.lut.dao;

import com.lut.domain.Student;
import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;

import java.util.List;

/**
 * @author Roy
 * @date 2020/6/27 16:17
 */
public interface IStudentDao {
    //查詢所有
    @Select("select * from student")
    List<Student> findAll();
    //插入數據
    @Insert("insert into student (stuName,major,sex,age)values(#{stuName},#{major},#{sex},#{age})")
    void saveUser(Student student);
    //更新學生信息
    @Update("update student set stuName=#{stuName},sex=#{sex},major=#{major},age=#{age} where id=#{id}")
    void  updateUser(Student student);
    //根據id刪除學生
    @Delete("delete from student where id=#{id}")
    void deleteUser(Integer id);
    //根據id查詢學生信息
    @Select("select * from student where id=#{id}")
    Student findById(Integer id);
    //模糊查詢根據姓名
    @Select("select * from student where stuName like #{stuName}")
    List<Student> findByName(String stuName);
    //查詢學生總數
    @Select("select count(*) from student")
    int findTotalUser();
}

2.在test包下java包下新建java命名爲：com.lut.StudentTest
並在其中加入測試方法的代碼如下:

package com.lut;

import com.lut.dao.IStudentDao;
import com.lut.domain.Student;
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 org.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.io.InputStream;
import java.util.Date;
import java.util.List;

/**
 * @author Roy
 * @date 2020/6/27 16:35
 */
public class StudentTest {
    private SqlSessionFactory factory;
    private SqlSession session;
    private IStudentDao studentDao;
    private InputStream in;
    @Before
    public void init()throws Exception{
        in=Resources.getResourceAsStream("SqlMapConfig.xml");
        factory=new SqlSessionFactoryBuilder().build(in);
        session=factory.openSession();
        studentDao=session.getMapper(IStudentDao.class);
    }
    @After
    public void destroy()throws Exception{
        session.commit();
        session.close();
        in.close();
    }
    //測試存儲
    @Test
    public void testSave(){
        Student student=new Student();
        student.setStuName("jack");
        student.setSex("M");
        student.setMajor("English");
        student.setAge(40);
        studentDao.saveStudent(student);
    }
    //測試更新
    @Test
    public void testUpdate(){
        Student student=new Student();
        student.setStuName("道家");
        student.setMajor("道教");
        student.setSex("男");
        student.setAge(1500);
        student.setId(1);
        studentDao.updateStudent(student);
    }
    //測試根據id刪除
    @Test
    public void testDelete(){
        studentDao.deleteStudent(1);
    }
    //測試根據id查詢
    @Test
    public void testFindOne(){
        Student student=studentDao.findById(3);
        System.out.println(student);
    }
    //測試模糊查詢
    @Test
    public void testFindByName(){
        List<Student> students =studentDao.findByName("%jack%");
        for(Student student:students){
            System.out.println(student);
        }
    }
    //測試查詢用戶總數
    @Test
    public void testFindTotal(){
        int total=studentDao.findTotalUser();
        System.out.println(total);
    }

}

測試全部通過正確運行。
注意其中數據庫中的student表是在mysql中database：mybatis中新建的student表其中表字段如下圖所示