本文内容纲要：

- Cannot change version of project facet Dynamic Web Module to 3.0

1、Eclipse创建maven project

创建完成后报错：The superclass "javax.servlet.http.HttpServlet" was not found on the Java Build Path

解决方法：右键项目-->propertites--->Project facets---Run time里勾选配置好的tomcat，点击oK，错误消失

如果没有安装好tomcat，请自行安装后。

如果工程中没有显示maven Dependency，在本地的classpath文件中增加后就会显示

Cannot change version of project facet Dynamic Web Module to 3.0

Go to your workspace>>Project folder>>.settings >>org.eclipse.wst.common.project.facet.core.xml. Open and edit it as per your convenience. Let me know if it solves the problem.

<?xml version="1.0" encoding="UTF-8"?> <faceted-project> <fixed facet="wst.jsdt.web"/> <installed facet="java" version="1.8"/> <installed facet="jst.web" version="3.1"/> <installed facet="wst.jsdt.web" version="1.0"/> </faceted-project>

2、增加springmvc 所需jar 包

　　　　两个maven依赖，spring-context；spring-mvc。maven就会自动下载所有关联的jar包，包括

spring-webmvc
spring-beans
spring-core
spring-expression
spring-web
spring-context
spring-aop
aopalliance
commons-logging

所以只需在pom文件里增加如下：

<!-- 配置Spring MVC jar -->
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>4.3.3.RELEASE</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>4.3.3.RELEASE</version>
        </dependency>

问题：

maven提示invalid LOC header (bad signature)的解决办法，删除仓库的jar文件，重新update project

在工程中增加3个source folder，分别为src/main/java, src/main/resources,src/test/java. 工程如下所示：

在项目中增加src/main/webapp目录，把source folder中webapp目录下文件copy进去，删除掉自己创建的src。完善webapp目录如下

配置webapp目录为webroot目录，

配置完成后，修改web.xml文件，如下：

<?xml version="1.0" encoding="UTF-8"?>
<web-app  version="3.1" xmlns="http://xmlns.jcp.org/xml/ns/javaee"  
                        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                        xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee 
                                            http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd">
        
     <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/applicationContext.xml</param-value>
        <!-- 默认是/WEB-INF/applicationContext.xml -->
     </context-param>
     
     <listener>
        <listener-class>
            org.springframework.web.context.ContextLoaderListener
        </listener-class>
     </listener>
  
    <servlet>
        <servlet-name>SpringMVC</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>/WEB-INF/SpringMVC-servlet.xml</param-value>
            <!-- 默认是/WEB-INF/[servlet名字]-servlet.xml -->
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    
    <servlet-mapping>
        <servlet-name>SpringMVC</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
  
</web-app>

在WEB-INF目录下创建applicationContext.xml和servletName-servlet.xml

applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
                           http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
                           http://www.springframework.org/schema/tx
                           http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
                           http://www.springframework.org/schema/aop
                           http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
                           http://www.springframework.org/schema/context
                           http://www.springframework.org/schema/context/spring-context-4.0.xsd">

</beans>

SpringMVC-servlet.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xsi:schemaLocation="http://www.springframework.org/schema/beans 
                        http://www.springframework.org/schema/beans/spring-beans-4.0.xsd 
                        http://www.springframework.org/schema/mvc 
                        http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd 
                        http://www.springframework.org/schema/context 
                        http://www.springframework.org/schema/context/spring-context-4.0.xsd 
                        http://www.springframework.org/schema/aop 
                        http://www.springframework.org/schema/aop/spring-aop-4.0.xsd 
                        http://www.springframework.org/schema/tx 
                        http://www.springframework.org/schema/tx/spring-tx-4.0.xsd">
    <!-- 设置使用注解的类所在的jar包 -->
    <context:component-scan base-package="hello" />
</beans>

增加contorller类

package helloTest;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
public class HelloController {
    @RequestMapping("/hello")
    public @ResponseBody String testHello() {
        return "Hello,spring mvc";
    }

}

在SpringMVC-servlet.xml增加设置使用注解的类所在的jar包

<context:component-scan base-package="helloTest" />

部署tomcat，执行测试

这时已完成所有环境搭建工作，引用 xingoo 的博客总结如下：

1 两个maven依赖，spring-context；spring-mvc。maven就会自动下载所有关联的jar包，包括

spring-webmvc
spring-beans
spring-core
spring-expression
spring-web
spring-context
spring-aop
aopalliance
commons-logging

2 一个web.xml文件，配置了listener和servlet
3 两个spring相关的文件，applicationContext.xml和servletName-servlet.xml
4 一个controller文件，配置了拦截的url处理代码

本文内容总结：Cannot change version of project facet Dynamic Web Module to 3.0，

原文链接：https://www.cnblogs.com/hylinux/p/6043437.html

【Spring实战4】10--搭建SpringMVC环境

本文内容纲要：

Cannot change version of project facet Dynamic Web Module to 3.0