Idea+Tomcat+Spring Boot 404

//启动类Application
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;

@SpringBootApplication
public class Application extends SpringBootServletInitializer {

    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(Application.class);
    }

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

//pom.xml 设置
<dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-tomcat</artifactId>
      <scope>provided</scope>
</dependency>

//pom.xml 设置packaging的值war
<groupId>com.example</groupId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>
<description>Demo project for Spring Boot</description>