second commit

pom.xml

@@ -40,6 +40,10 @@
             <artifactId>mybatis-spring-boot-starter</artifactId>
             <version>2.2.0</version>
         </dependency>
+        <dependency>
+            <groupId>org.mariadb.jdbc</groupId>
+            <artifactId>mariadb-java-client</artifactId>
+        </dependency>
     </dependencies>
 
 

src/main/java/com/ai/SimpleSpringbootProjectApplication.java

 package com.ai;
 
+import org.apache.ibatis.annotations.Mapper;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 

src/main/java/com/ai/controller/UserController.java

 package com.ai.controller;
 
+import com.ai.service.UserService;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.web.bind.annotation.CrossOrigin;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
@@ -9,6 +11,13 @@ import org.springframework.web.bind.annotation.RestController;
 @RequestMapping("/user")
 public class UserController {
 
+    @Autowired
+    private UserService userService;
 
+    // http://localhost:8081/user/findAllUser
+    @RequestMapping("/findAllUser")
+    public String findAllUser() {
+        return userService.findAllUser().toString();
+    }
 
 }

src/main/java/com/ai/mapper/UserMapper.java

+package com.ai.mapper;
+
+import com.ai.pojo.User;
+
+import java.util.List;
+
+public interface UserMapper {
+
+    List<User> findAllUser();
+
+}

src/main/java/com/ai/service/UserService.java

@@ -5,5 +5,7 @@ import com.ai.pojo.User;
 import java.util.List;
 
 public interface UserService {
+
     List<User> findAllUser();
+
 }

src/main/java/com/ai/service/impl/UserServiceImpl.java

 package com.ai.service.impl;
 
+import com.ai.mapper.UserMapper;
 import com.ai.pojo.User;
 import com.ai.service.UserService;
+import com.ai.util.MyBatisUtils;
+import org.apache.ibatis.session.SqlSession;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
 
 import java.util.List;
 
+@Service
 public class UserServiceImpl implements UserService {
 
     @Override
     public List<User> findAllUser() {
-
-        return null;
+        SqlSession sqlSession = MyBatisUtils.getSqlSession();
+        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
+        return mapper.findAllUser();
     }
+
 }

src/main/java/com/ai/util/MyBatisUtils.java

+package com.ai.util;
+
+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.IOException;
+import java.io.InputStream;
+
+public class MyBatisUtils {
+
+    private static SqlSessionFactory factory = null;
+
+    static {
+        String config = "mybatis-config.xml"; // 需和项目中的主配置文件名一样
+        try {
+            // 读取config表示的文件
+            InputStream input = Resources.getResourceAsStream(config);
+            // 创建SqlSessionFactory对象
+            factory = new SqlSessionFactoryBuilder().build(input);
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+
+    public static SqlSession getSqlSession() {
+        SqlSession sqlSession = null;
+        if (factory != null) {
+            // 从SqlSessionFactory中获取SqlSession对象
+            sqlSession = factory.openSession(); // 非自动提交事务
+        }
+        return sqlSession;
+    }
+
+}

src/main/resources/application.yml

 server:
   port: 8081
+
+spring:
+  datasource:
+    url: jdbc:mariadb://localhost:3307/mybatis_test
+    username: root
+    password: 123
+    driver-class-name: org.mariadb.jdbc.Driver
\ No newline at end of file

src/main/resources/com.ai/mapper/UserMapper.xml

+<?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.ai.mapper.UserMapper">
+
+    <select id="findAllUser" resultType="com.ai.pojo.User">
+        select * from user;
+    </select>
+
+</mapper>

src/main/resources/mybatis-config.xml

+<?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>
+
+    <settings>
+        <setting name="logImpl" value="STDOUT_LOGGING"/>
+    </settings>
+
+    <environments default="development">
+        <environment id="development">
+            <transactionManager type="JDBC"/>
+            <dataSource type="POOLED">
+                <property name="driver" value="org.mariadb.jdbc.Driver"/>
+                <property name="url" value="jdbc:mariadb://localhost:3307/mybatis_test"/>
+                <property name="username" value="root"/>
+                <property name="password" value="123"/>
+            </dataSource>
+        </environment>
+    </environments>
+
+    <mappers>
+        <package name="com.ai.mapper"/>
+    </mappers>
+
+</configuration>