我使用的是springboot+mybatisplus +mysql
1.创建一个SpringUtil工具类

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
public final class SpringUtil implements ApplicationContextAware {
    private static ApplicationContext applicationContext = null;
    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        // TODO Auto-generated method stub
        if (SpringUtil.applicationContext == null) {
            SpringUtil.applicationContext = applicationContext;
            System.out.println("=============================================="+
                    "========ApplicationContext配置成功,在普通类可以通过调用ToolSpring.getAppContext()获取applicationContext对象,applicationContext="
                            + applicationContext + "==========");
        }
    }
    public static ApplicationContext getApplicationContext() {
        return applicationContext;
    }
    //通过类名称获取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);
    }
}

 

2.在启动类上面添加注解

@Import(SpringUtil.class)
依赖 import org.springframework.context.annotation.Import;

3.在普通类中使用SpringUtil创建service类
 

  TestService testService = (TestService )SpringUtil.getBean(TestService.class);
  testService.save(testEntity);

这里强转了一下,我试了下不强转也没问题
此时就可以使用testService里的方法来和数据库交互了