1. 將SpringBoot的項目的打包方式設置為war

 <groupId>com.example</groupId>  
<artifactId>demo</artifactId>  
<version>1.0.0</version>  
<packaging>war</packaging>

2. 移除內嵌的tomcat模塊，但是為了我們在本機測試方便，我們還需要引入它，所以配置如下

<dependency>  
        <groupId>org.springframework.boot</groupId>  
        <artifactId>spring-boot-starter-web</artifactId>  
        <exclusions>  
            <exclusion>  
                <groupId>org.springframework.boot</groupId>  
                <artifactId>spring-boot-starter-tomcat</artifactId>  
            </exclusion>  
        </exclusions>  
</dependency>  
<dependency>  
        <groupId>org.springframework.boot</groupId>  
        <artifactId>spring-boot-starter-tomcat</artifactId>  
        <scope>provided</scope>  
</dependency>  

3. 添加tomcat-servelt-api依賴

<dependency>  
      <groupId>org.apache.tomcat</groupId>  
      <artifactId>tomcat-servlet-api</artifactId>  
      <version>7.0.42</version>  
      <scope>provided</scope>  
</dependency>  

4. 修改入口方法 繼承一個SpringBootServletInitializer類，并且覆蓋configure方法

package com.example;  
  
   import org.springframework.boot.SpringApplication;  
import org.springframework.boot.autoconfigure.SpringBootApplication;  
import org.springframework.boot.builder.SpringApplicationBuilder;  
import org.springframework.boot.web.support.SpringBootServletInitializer;  
import org.springframework.cache.annotation.EnableCaching;  
  
   @SpringBootApplication  
@EnableCaching  
public class SpringDataJpaExampleApplication extends SpringBootServletInitializer {  
  
    @Override  
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {  
        return application.sources(SpringDataJpaExampleApplication.class);  
    }  
  
    public static void main(String[] args) {  
        SpringApplication.run(SpringDataJpaExampleApplication.class, args);  
    }  
}  

5. 添加war插件，用來自定義打包以后的war包的名稱

<plugin>  
      <groupId>org.apache.maven.plugins</groupId>  
      <artifactId>maven-war-plugin</artifactId>  
      <configuration>  
          <warSourceExcludes>src/main/resources/**</warSourceExcludes>  
          <warName>springboot</warName>  
      </configuration>  
</plugin>  

引入上面這個插件，是避免maven打包的時候為我們默認的一個帶有版本號的war包名稱，因為我們部署到tomcat以后，在訪問項目的時候，需要用到這個war包的名稱