我们运行springboot2的项目，都是打包成一个jar包然后用自带的tomcat启动，简单明了，但是如果要修改jar包中的一些页面就得重新打包，所以有时候我们想要将springboot2的应用发布到tomcat容器中，其实很简单，步骤如下：

1、pom.xml中把项目类型改为war

  <modelVersion>4.0.0</modelVersion>
  <groupId>com.suibibk</groupId>
  <artifactId>testtomcat</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>war</packaging>

2、排除自带的tomcat

<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>

3、pom.xml中加入tomcat好本地调试

<dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-tomcat</artifactId>
      <scope>provided</scope><!-- 必须要加，不然报错 -->
    </dependency>
      <dependency>
          <groupId>javax.servlet</groupId>
          <artifactId>javax.servlet-api</artifactId>
          <scope>provided</scope>
  </dependency>

provided表示只在本地调试起作用

4、修改启动类

@SpringBootApplication
public class App extends SpringBootServletInitializer {
    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder builder) {
        return builder.sources(App.class);
    }
    public static void main(String[] args) {
        SpringApplication.run(App.class, args);
    }
}

改为继承SpringBootServletInitializer

5、修改tomcat的server.xml指定端口

<Service name="Catalina">
    <Connector port="8082"   protocol="HTTP/1.1" maxThreads="700" acceptCount="100" connectionTimeout="2000" redirectPort="8445" URIEncoding="UTF-8"/>
    <Engine name="Catalina" defaultHost="localhost">
        <Host name="localhost" appBase="webapps">
          <Context docBase="testtomcat" path="" reloadable="true" />
        </Host>
    </Engine>
  </Service>

6、完成，下面提供完整的pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.suibibk</groupId>
  <artifactId>testtomcat</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>war</packaging>
  <parent>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-parent</artifactId>
      <version>2.0.5.RELEASE</version>
  </parent>
  <dependencies>
      <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>
      <!-- jsp的话还需要tomcat的支持 ，自带的tomcat不支持-->
      <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-tomcat</artifactId>
      <scope>provided</scope><!-- 必须要加，不然报错 -->
    </dependency>
      <dependency>
          <groupId>javax.servlet</groupId>
          <artifactId>javax.servlet-api</artifactId>
          <scope>provided</scope>
  </dependency>
  </dependencies>
  <build>
    <finalName>testtomcat</finalName>
    <plugins>
            <!-- 可以将项目打包成可执行jar包 -->
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
  </build>
</project>