个人觉得可能没有解析到application.properties文件
application.properties配置文件如下：
spring.mail.host=smtp.qq.com
spring.mail.username=******@qq.com
spring.mail.password=1222222
spring.mail.properties.mail.smtp.auth=true
spring.mail.properties.mail.smtp.starttls.enable=true
spring.mail.properties.mail.smtp.starttls.required=true
application.java如下：
@SpringBootApplication
@EnableAutoConfiguration
public class MonitorApplication {
public static void main(String[] args) {
SpringApplication.run(MonitorApplication.class, args);
}
}
