SpringMVC （一）springMVC环境的搭建

1.新建maven工程，选择骨架创建，web-app

2.完善目录结构，添加java与resources

3.maven导入依赖

<!--版本控制-->
<properties>
  <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  <maven.compiler.source>1.8</maven.compiler.source>
  <maven.compiler.target>1.8</maven.compiler.target>
  <spring.version>5.0.2.RELEASE</spring.version>
</properties>

<dependencies>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-context</artifactId>
    <version>${spring.version}</version>
  </dependency>

  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-web</artifactId>
    <version>${spring.version}</version>
  </dependency>

  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
    <version>${spring.version}</version>
  </dependency>

  <dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>servlet-api</artifactId>
    <version>2.5</version>
    <scope>provided</scope>
  </dependency>

  <dependency>
    <groupId>javax.servlet.jsp</groupId>
    <artifactId>jsp-api</artifactId>
    <version>2.0</version>
    <scope>provided</scope>
  </dependency>
</dependencies>

4.配置前端控制器，在WEB_INF>>>web.xml

<web-app>
  <display-name>Archetype Created Web Application</display-name>

  <filter>
    <filter-name>characterEncodingFilter</filter-name>
    <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
    <init-param>
      <param-name>encoding</param-name>
      <param-value>UTF-8</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>characterEncodingFilter</filter-name>
    <url-pattern>/</url-pattern>
  </filter-mapping>

  <servlet>
    <servlet-name>dispatcherServlet</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>

    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:springmvc.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>

  <servlet-mapping>
    <servlet-name>dispatcherServlet</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
</web-app>

5.配置spring resources>>>springmvc.xml文件

作用：开启注解扫描，通过前端控制器调用springmvc.xml,将类加载进容器

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

    <!-- 配置spring创建容器时要扫描的包 -->
    <context:component-scan base-package="com.qunar"></context:component-scan>
    <!-- 配置spring开启注解mvc的支持-->
    <mvc:annotation-driven></mvc:annotation-driven>
</beans>

6.配置tomcat

7.编写代码

@Controller
@RequestMapping(path = "/test")
@ResponseBody
public class HelloController {
    @RequestMapping(path="/hello")
    public String sayHello(String info){
        System.out.println("hello springMVC"+info);
        return "success";
    }
    @RequestMapping(path = "/testRequestMapping")
    public String testRequestMapping(){
        System.out.println("测试RequeMapping注解");
        return "success";
    }
}

请求:localhost:8080/test/hello?info=输入的信息 请求响应:hello springMVC输入的信息

8.springmvc执行流程

9.中文乱码的解决办法

• post 请求方式:通过配置过滤器解决

<web-app>
  <display-name>spring_study</display-name>

  <!--配置前端过滤器-->
  <filter>
    <filter-name>characterEncodingFilter</filter-name>
    <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
    <!-- 设置过滤器中的属性值 -->
    <init-param>
      <param-name>encoding</param-name>
      <param-value>UTF-8</param-value>
    </init-param>
    <!-- 启动过滤器 -->
    <init-param>
      <param-name>forceEncoding</param-name>
      <param-value>true</param-value>
    </init-param>
  </filter>
  <!-- 过滤所有请求 -->
  <filter-mapping>
    <filter-name>characterEncodingFilter</filter-name>
    <url-pattern>/</url-pattern>
  </filter-mapping>


  <!--配置前端控制器-->
  <servlet>
    <servlet-name>dispatcherServlet</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:springmvc.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>dispatcherServlet</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

</web-app>

在 springmvc 的配置文件中可以配置,静态资源不过滤:

<mvc:resources location="/css/" mapping="/css/**"/>
<mvc:resources location="/images/" mapping="/images/**"/>
<mvc:resources location="/scripts/" mapping="/javascript/**"/>

• get方式：GET 请求的编码问题,要改 tomcat 的 server.xml

<Connector connectionTimeout="20000" port="8080" protocol="HTTP/1.1" redirectPort="8443"/>
改为:
<Connector connectionTimeout="20000" port="8080" protocol="HTTP/1.1" redirectPort="8443" useBodyEncodingForURI="true"/>

如果遇到 ajax 请求仍然乱码,请把:useBodyEncodingForURI="true"改为 URIEncoding="UTF-8"即可。