Mybatis以main方法形式调用dao层执行代码实例

package com.ljf.util;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;
/**
 * @ClassName: SpringUtil
 * @Description: TODO
 * @Author: admin
 * @Date: 2023/04/08 19:58:05 
 * @Version: V1.0
 **/
@Component
public class SpringUtil implements ApplicationContextAware {
    private static ApplicationContext applicationContext = null;
    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        if(SpringUtil.applicationContext == null){
            SpringUtil.applicationContext  = applicationContext;
        }
    }
    //获取applicationContext
    public static ApplicationContext getApplicationContext() {
        return applicationContext;
    }
    //通过name获取 Bean.
    public static Object getBean(String name){
        return getApplicationContext().getBean(name);
    }
    //通过class获取Bean.
    public static <T> T getBean(Class<T> clazz){
        return getApplicationContext().getBean(clazz);
    }
    //通过name,以及Clazz返回指定的Bean
    public static <T> T getBean(String name,Class<T> clazz){
        return getApplicationContext().getBean(name, clazz);
    }
}

    <!-- springBoot的启动器 -->
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</artifactId>
      <version>2.0.1.RELEASE</version>
    </dependency>
    <!-- web启动器 -->
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-thymeleaf</artifactId>
      <version>2.0.1.RELEASE</version>
    </dependency>
    <!-- Mybatis启动器 -->
    <dependency>
      <groupId>org.mybatis.spring.boot</groupId>
      <artifactId>mybatis-spring-boot-starter</artifactId>
      <version>1.1.1</version>
    </dependency>
    <!-- mysql数据库驱动 -->
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>5.1.3</version>
    </dependency>
    <!-- druid数据库连接池 -->
    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>druid</artifactId>
      <version>1.0.9</version>
    </dependency>

<?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>
    <!-- 全局参数 -->
    <settings>
        <!-- 使全局的映射器启用或禁用缓存 -->
        <setting name="cacheEnabled"             value="true"   />
        <!-- 允许JDBC 支持自动生成主键 -->
        <setting name="useGeneratedKeys"         value="true"   />
        <!-- 配置默认的执行器.SIMPLE就是普通执行器;REUSE执行器会重用预处理语句(prepared statements);BATCH执行器将重用语句并执行批量更新 -->
        <setting name="defaultExecutorType"      value="SIMPLE" />
        <!-- 指定 MyBatis 所用日志的具体实现 -->
        <setting name="logImpl"                  value="SLF4J"  />
        <!-- 使用驼峰命名法转换字段 -->
        <!-- <setting name="mapUnderscoreToCamelCase" value="true"/> -->
    </settings>
</configuration>

server:
  port: 8084
spring:
  datasource:
    driverClassName: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/test_db
    username: root
    password: cloudiip
    type: com.alibaba.druid.pool.DruidDataSource
mybatis:
  mapper-locations: classpath:mapper/*.xml
  type-aliases-package: com.ljf.model
    # 加载全局的配置文件
  configuration-properties: classpath:mybatis/mybatis-config.xml
  configuration:
    #增加打印sql语句，一般用于本地开发测试
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
logging:
  level:
    com.ljf.mapper: debug
  #分页插件
  pagehelper:
    helper-dialect: mysql
    params: count=countSql
    reasonable: true    #开启优化，如果开启优化，在分页页码结果没有数据的时候,会显示有数据的页码数据
    support-methods-arguments: true #是否支持接口参数来传递分页参数，默认false

@SpringBootApplication
@MapperScan("com.ljf.mapper")
//@ComponentScan("com.ljf")
public class MainAppExe {
    public static void main(String[] args) {
        SpringApplication.run(MainAppExe.class, args);
        //调用Sercice层
        ApplicationContext context = SpringUtil.getApplicationContext();
        OrderService userService = context.getBean(OrderService.class);// 注意是Service，不是ServiceImpl
        List<Order> dataList=userService.queryOrderList();
        dataList.stream().forEach((x)->{System.out.println("x；"+x.getOrderName());});
        System.out.println();
        //结束进程
       System.exit(0);
    }
}