<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-web</artifactId>
  <!-- 移除嵌入式tomcat插件 -->
  <exclusions>
    <exclusion>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-tomcat</artifactId>
    </exclusion>
  </exclusions>
</dependency>

<dependency>
  <groupId>javax.servlet</groupId>
  <artifactId>javax.servlet-api</artifactId>
  <version>3.1.0</version>
  <scope>provided</scope>
</dependency>
<dependency>
  <groupId>org.apache.tomcat</groupId>
  <artifactId>tomcat-servlet-api</artifactId>
  <version>8.0.36</version>
  <scope>provided</scope>
</dependency>

@SpringBootApplication
public class Application {
  public static void main(String[] args) {
    SpringApplication.run(Application.class, args);
  }
}

/**
 * 修改启动类，继承 SpringBootServletInitializer 并重写 configure 方法
 */
public class SpringBootStartApplication extends SpringBootServletInitializer {
  @Override
  protected SpringApplicationBuilder configure(SpringApplicationBuilder builder) {
    // 注意这里要指向原先用main方法执行的Application启动类
    return builder.sources(Application.class);
  }
}