springmvc的使用

1）创建项目（web项目），导入依赖；

下面是pom.xml文件的相关配置：

<?xml version="1.0" encoding="UTF-8"?>

<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.seecen</groupId>
  <artifactId>springmvc</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>war</packaging>

  <name>springmvc Maven Webapp</name>
  <!-- FIXME change it to the project's website -->
  <url>http://www.example.com</url>

  <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>5.0.3.RELEASE</spring.version>
    <jstl.version>1.2</jstl.version>
    <servlet-api.version>4.0.0</servlet-api.version>
    <jsp-api.version>2.3.1</jsp-api.version>
    <jackson.version>2.9.0</jackson.version>
    <commons-fileupload.version>1.3.3</commons-fileupload.version>
  </properties>

  <dependencies>
    <!--单元测试-->
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
    </dependency>
    <!--springmvc -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <!-- JSP相关 -->
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>jstl</artifactId>
      <version>${jstl.version}</version>
    </dependency>
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>javax.servlet-api</artifactId>
      <version>${servlet-api.version}</version>
      <scope>provided</scope>
    </dependency>
    <dependency>
      <groupId>javax.servlet.jsp</groupId>
      <artifactId>javax.servlet.jsp-api</artifactId>
      <version>${jsp-api.version}</version>
      <scope>provided</scope>
    </dependency>
    <!--json处理-->
    <!--实际上为三个包，但是导入databind会自动导入其他两个包-->
    <dependency>
      <groupId>com.fasterxml.jackson.core</groupId>
      <artifactId>jackson-databind</artifactId>
      <version>${jackson.version}</version>
    </dependency>

    <!--文件上传组件-->
    <dependency>
      <groupId>commons-fileupload</groupId>
      <artifactId>commons-fileupload</artifactId>
      <version>${commons-fileupload.version}</version>
    </dependency>

  </dependencies>

  <build>
    <finalName>springmvc</finalName>
    <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
      <plugins>
        <plugin>
          <artifactId>maven-clean-plugin</artifactId>
          <version>3.1.0</version>
        </plugin>
        <!-- see http://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_war_packaging -->
        <plugin>
          <artifactId>maven-resources-plugin</artifactId>
          <version>3.0.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-compiler-plugin</artifactId>
          <version>3.8.0</version>
        </plugin>
        <plugin>
          <artifactId>maven-surefire-plugin</artifactId>
          <version>2.22.1</version>
        </plugin>
        <plugin>
          <artifactId>maven-war-plugin</artifactId>
          <version>3.2.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-install-plugin</artifactId>
          <version>2.5.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-deploy-plugin</artifactId>
          <version>2.8.2</version>
        </plugin>
      </plugins>
    </pluginManagement>
  </build>
</project>

2）配置web.xml文件，在web.xml文件中配置springmvc；

<!DOCTYPE web-app PUBLIC
 "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
 "http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
  <display-name>Archetype Created Web Application</display-name>
<!--  配置springmvc核心servlet-->
  <servlet>
    <servlet-name>springmvc</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
<!--      指定springmvc配置文件路径-->
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath*:springmvc.xml</param-value>
    </init-param>
<!--    设置springmvc的dispatcherServlet随web容器一起加载-->
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>springmvc</servlet-name>
<!--    以/开头的所有请求-->
    <url-pattern>/</url-pattern>
  </servlet-mapping>
</web-app>

3）配置springmvc配置文件；

<!--开启注解驱动-->
    <mvc:annotation-driven/>
<!--    配置扫描包  会扫描包下打了@Controller注解的类，将其指定为springmvc控制层的类-->
    <context:component-scan base-package="controller"/>

4）创建springmvc控制层类Controller  添加@Controller注解；

@Controller
public class HelloController {
    //springmvc的处理方法
    // RequestMapping:指定方法对应的请求地址
    //return:页面地址，表示方法执行完成之后跳转到对应的页面(转发)
    @RequestMapping("/hello")
    public String hello(){
        System.out.println("进入hello方法");
        return "index.jsp";
    }
}

5）创建springmvc处理请求的方法 并在方法上添加@RequestMapping注解指定方法的请求地址；

6）部署项目，运行访问。如果能访问成功，则springmvc基础环境搭建成功；

如果测试结果在输出台能出现  “进入hello方法”，则说明测试成功；