idea创建web项目

骨架创建，那块打勾，删除多余xml里的行，main里directory创建缺的java和resources

<!--设置jdk-->
<properties>
  <maven.compiler.source>11</maven.compiler.source>
  <maven.compiler.target>11</maven.compiler.target>
</properties>

<!--设置tomcat7执行能更快些-->
<build>
  <plugins>
    <plugin>
      <groupId>org.apache.tomcat.maven</groupId>
      <artifactId>tomcat7-maven-plugin</artifactId>
      <version>2.2</version>
    </plugin>
  </plugins>
</build>

<!--设置端口号和访问路径-->
<build>
  <plugins>
    <plugin>
      <groupId>org.apache.tomcat.maven</groupId>
      <artifactId>tomcat7-maven-plugin</artifactId>
      <version>2.2</version>
      <configuration>
        <port>80</port>
        <path>/</path>
      </configuration>
    </plugin>
  </plugins>
</build>

使用servlet依赖

<dependencies>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.1.0</version>
        <scope>provided</scope>
    </dependency>
</dependencies>