mybatis--快速入门

springboot-mybatis-quickstart/.gitignore

@@ -0,0 +1,33 @@
+HELP.md
+target/
+!.mvn/wrapper/maven-wrapper.jar
+!**/src/main/**/target/
+!**/src/test/**/target/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+build/
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### VS Code ###
+.vscode/

springboot-mybatis-quickstart/pom.xml

@@ -0,0 +1,88 @@
+<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>com.inmind</groupId>
+    <artifactId>springboot-mybatis-quickstart</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>springboot-mybatis-quickstart</name>
+    <description>springboot-mybatis-quickstart</description>
+    <properties>
+        <java.version>11</java.version>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+        <spring-boot.version>2.7.6</spring-boot.version>
+    </properties>
+    <dependencies>
+        <!--mybatis框架起步依赖-->
+        <dependency>
+            <groupId>org.mybatis.spring.boot</groupId>
+            <artifactId>mybatis-spring-boot-starter</artifactId>
+            <version>2.3.0</version>
+        </dependency>
+
+        <!--mysql驱动包，操作哪一个数据库，配置对应数据库的驱动-->
+        <dependency>
+            <groupId>com.mysql</groupId>
+            <artifactId>mysql-connector-j</artifactId>
+            <scope>runtime</scope>
+        </dependency>
+        <!--之前版本的驱动包，部分企业还在使用-->
+        <!--<dependency>
+            <groupId>com.mysql</groupId>
+            <artifactId>mysql-connector-java</artifactId>
+            <scope>runtime</scope>
+        </dependency>-->
+
+        <!--单元测试依赖-->
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+    <dependencyManagement>
+        <dependencies>
+            <dependency>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-dependencies</artifactId>
+                <version>${spring-boot.version}</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
+        </dependencies>
+    </dependencyManagement>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.8.1</version>
+                <configuration>
+                    <source>11</source>
+                    <target>11</target>
+                    <encoding>UTF-8</encoding>
+                </configuration>
+            </plugin>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+                <version>${spring-boot.version}</version>
+                <configuration>
+                    <mainClass>com.inmind.SpringbootMybatisQuickstartApplication</mainClass>
+                    <skip>true</skip>
+                </configuration>
+                <executions>
+                    <execution>
+                        <id>repackage</id>
+                        <goals>
+                            <goal>repackage</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+
+</project>

springboot-mybatis-quickstart/src/main/java/com/inmind/SpringbootMybatisQuickstartApplication.java

@@ -0,0 +1,13 @@
+package com.inmind;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class SpringbootMybatisQuickstartApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(SpringbootMybatisQuickstartApplication.class, args);
+    }
+
+}

springboot-mybatis-quickstart/src/main/java/com/inmind/mapper/UserMapper.java

@@ -0,0 +1,16 @@
+package com.inmind.mapper;
+
+import com.inmind.pojo.User;
+import org.apache.ibatis.annotations.Mapper;
+import org.apache.ibatis.annotations.Select;
+
+import java.util.List;
+
+/*
+专门操作用户表的Mapper接口
+ */
+@Mapper//mybatis在运行时，会自动生成该接口的实现类（代理对象），并且将该对象交给Spring容器管理（Bean对象）
+public interface UserMapper {
+    @Select("select * from user")
+    public List<User> list();
+}

springboot-mybatis-quickstart/src/main/java/com/inmind/pojo/User.java

@@ -0,0 +1,71 @@
+package com.inmind.pojo;
+//对应User表的实体类
+public class User {
+    private Integer id;
+    private String name;
+    private Short age;
+    private Short gender;
+    private String phone;
+
+    public User() {
+    }
+
+    public User(Integer id, String name, Short age, Short gender, String phone) {
+        this.id = id;
+        this.name = name;
+        this.age = age;
+        this.gender = gender;
+        this.phone = phone;
+    }
+
+    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 Short getAge() {
+        return age;
+    }
+
+    public void setAge(Short age) {
+        this.age = age;
+    }
+
+    public Short getGender() {
+        return gender;
+    }
+
+    public void setGender(Short gender) {
+        this.gender = gender;
+    }
+
+    public String getPhone() {
+        return phone;
+    }
+
+    public void setPhone(String phone) {
+        this.phone = phone;
+    }
+
+    @Override
+    public String toString() {
+        return "User{" +
+                "id=" + id +
+                ", name='" + name + '\'' +
+                ", age=" + age +
+                ", gender=" + gender +
+                ", phone='" + phone + '\'' +
+                '}';
+    }
+}

springboot-mybatis-quickstart/src/main/resources/application.properties

@@ -0,0 +1,14 @@
+#下面这些内容是为了让MyBatis映射
+#指定Mybatis的Mapper文件
+mybatis.mapper-locations=classpath:mappers/*xml
+#指定Mybatis的实体目录
+mybatis.type-aliases-package=com.inmind.mybatis.entity
+
+#驱动类名称
+spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
+#数据库连接的url
+spring.datasource.url=jdbc:mysql://localhost:3306/mybatis2
+#连接数据库的用户名
+spring.datasource.username=root
+#连接数据库的密码
+spring.datasource.password=1234

springboot-mybatis-quickstart/src/test/java/com/inmind/SpringbootMybatisQuickstartApplicationTests.java

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+package com.inmind;
+
+import com.inmind.mapper.UserMapper;
+import com.inmind.pojo.User;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+
+import java.util.List;
+
+@SpringBootTest//在进行单元测试时，启动spring程序，启动IOC，将程序中Bean对象加载到容器
+class SpringbootMybatisQuickstartApplicationTests {
+
+    @Autowired
+    private UserMapper userMapper;//注入的是mybatis自动生成的UserMapper接口类型的实现类对象
+
+    @Test
+    void contextLoads() {
+    }
+
+    @Test
+    void testList(){
+        List<User> userList = userMapper.list();
+        //通过集合获取Stream流，进行遍历消费，user就是集合中的每个元素，拿到每个元素进行打印消费
+//        userList.stream().forEach(user -> System.out.println(user));
+        for (User user : userList) {
+            System.out.println(user);
+        }
+    }
+
+}

springboot-web-req-resp/src/main/java/com/inmind/SpringbootWebReqRespApplication.java

@@ -2,6 +2,7 @@ package com.inmind;
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.ComponentScan;
 
 @SpringBootApplication
 public class SpringbootWebReqRespApplication {

springboot-web-req-resp/src/main/java/com/inmind/controller/EmpController.java

@@ -6,16 +6,22 @@ import com.inmind.service.EmpService;
 import com.inmind.service.impl.EmpServiceImplA;
 import com.inmind.utils.XmlParserUtils;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.stereotype.Component;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 
+import javax.annotation.Resource;
 import java.util.List;
 
 @RestController
 public class EmpController {
 
-    @Autowired //运行时，IOC容器会提供该类型的bean对象，并赋值给该变量---依赖注入
+    /*@Autowired //运行时，IOC容器会提供该类型的bean对象，并赋值给该变量---依赖注入
+    @Qualifier("empServiceImplB")//当依赖注入EmpService类型的bean对象时，优先使用@Qualifier书写的bean对象名称对应的对象
+    private EmpService empService;*/
+
+    @Resource(name = "empServiceImplA")
     private EmpService empService;
 
 

springboot-web-req-resp/src/main/java/com/inmind/dao/impl/EmpDaoImplA.java

@@ -3,7 +3,6 @@ package com.inmind.dao.impl;
 import com.inmind.dao.EmpDao;
 import com.inmind.pojo.Emp;
 import com.inmind.utils.XmlParserUtils;
-import org.springframework.stereotype.Component;
 import org.springframework.stereotype.Repository;
 
 import java.util.List;

springboot-web-req-resp/src/main/java/com/inmind/service/impl/EmpServiceImplA.java

@@ -1,11 +1,9 @@
 package com.inmind.service.impl;
 
 import com.inmind.dao.EmpDao;
-import com.inmind.dao.impl.EmpDaoImplA;
 import com.inmind.pojo.Emp;
 import com.inmind.service.EmpService;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.stereotype.Component;
 import org.springframework.stereotype.Service;
 
 import java.util.List;

springboot-web-req-resp/src/main/java/com/inmind/service/impl/EmpServiceImplB.java

@@ -0,0 +1,43 @@
+package com.inmind.service.impl;
+
+import com.inmind.dao.EmpDao;
+import com.inmind.pojo.Emp;
+import com.inmind.service.EmpService;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Primary;
+import org.springframework.stereotype.Service;
+
+import java.util.List;
+
+//@Component //将当前类交给IOC容器管理，成为IOC容器的bean--控制反转
+@Service
+//@Primary//当依赖注入EmpService类型的bean对象时，优先使用EmpServiceImplB
+public class EmpServiceImplB implements EmpService {
+    @Autowired
+    private EmpDao empDao;
+
+    @Override
+    public List<Emp> listEmp() {
+        //业务层从dao层获取数据
+        List<Emp> emps = empDao.listEmp();
+
+        //2.对数据进行转换处理
+        emps.stream().forEach(emp->{
+            //处理性别
+            if (emp.getGender().equals("1")) {
+                emp.setGender("男生");
+            }else{
+                emp.setGender("女生");
+            }
+            //处理职务
+            if (emp.getJob().equals("1")) {
+                emp.setJob("班主任");
+            } else if ("2".equals(emp.getJob())) {
+                emp.setJob("讲师");
+            } else {
+                emp.setJob("辅导员");
+            }
+        });
+        return emps;
+    }
+}