第一个SpringMVC项目
第一个SpringMVC项目
依赖
<dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.2.7.RELEASE</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/javax.servlet/servlet-api -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>servlet-api</artifactId>
            <version>2.5</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/javax.servlet.jsp/jsp-api -->
        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>jsp-api</artifactId>
            <version>2.2</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/javax.servlet/jstl -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>
    </dependencies>
方法一:基于配置实现
- 新建一个Moudle,添加web支持(在建好的Moudle上右击选择AddFrameworksSupport选择web支持)
- 配置tomcat,检查jar包是否存在(如果不存在会报404),具体方法如下:

 
- 写web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app 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_4_0.xsd"
         version="4.0">
    <!--1.注册DispatcherServlet-->
    <servlet>
        <servlet-name>springmvc</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <!--关联一个springmvc的配置文件:【servlet-name】-servlet.xml-->
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:springmvc-servlet.xml</param-value>
        </init-param>
        <!--启动级别-1-->
        <load-on-startup>1</load-on-startup>
    </servlet>
    <!--/ 匹配所有的请求;(不包括.jsp)-->
    <!--/* 匹配所有的请求;(包括.jsp)-->
    <!--  只要用户发的请求都被拦截  -->
    <servlet-mapping>
        <servlet-name>springmvc</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
</web-app>
- 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"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd">
    <bean class="org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping"/>
    <bean class="org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter"/>
    <!--视图解析器:DispatcherServlet给他的ModelAndView-->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" id="InternalResourceViewResolver">
        <!--前缀-->
        <property name="prefix" value="/WEB-INF/jsp/"/>
        <!--后缀-->
        <property name="suffix" value=".jsp"/>
    </bean>
    <!--Handler-->
    <bean id="/hello" class="com.wang.controller.HelloController"/>
</beans>
- 实现Controller接口
public class HelloController implements Controller {
    public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception {
        //ModelAndView 模型和视图
        //ModelAndView构造方法可以指定返回的页面名称,也可以通过setViewName()方法跳转到指定的页面
        //使用addObject()设置需要返回的值,addObject()有几个不同参数的方法,可以默认和指定返回对象的名字。
        ModelAndView mv = new ModelAndView();
        //封装对象,放在ModelAndView中。Model
        mv.addObject("msg","HelloSpringMVC!");
        //封装要跳转的视图,放在ModelAndView中
        mv.setViewName("hello");   //: /WEB-INF/jsp/hello.jsp
        return mv;
    }
}
- 写hello.jsp页面并启动tomcat测试
项目结构
 
方法二:基于注解实现(常用)
- 新建一个Moudle,添加web支持(在建好的Moudle上右击选择AddFrameworksSupport选择web支持)
- 配置tomcat,检查jar包是否存在(如果不存在会报404)
- web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app 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_4_0.xsd"
         version="4.0">
    <servlet>
        <servlet-name>springmvc</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:springmvc-servlet.xml</param-value>
        </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>
- 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:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        https://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/mvc
        https://www.springframework.org/schema/mvc/spring-mvc.xsd">
    <!-- 自动扫描包,让指定包下的注解生效,由IOC容器统一管理 -->
    <context:component-scan base-package="com.wang.controller"/>
    <!-- 让Spring MVC不处理静态资源  .css ,.html,.mp3 .... -->
    <mvc:default-servlet-handler />
    <mvc:annotation-driven />
    <!-- 视图解析器 -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" id="internalResourceViewResolver">
        <!-- 前缀 -->
        <property name="prefix" value="/WEB-INF/jsp/" />
        <!-- 后缀 -->
        <property name="suffix" value=".jsp" />
    </bean>
</beans>
- 创建Controller
@Controller
public class HelloController {
    @RequestMapping("/hello")    //用户.../hello请求时
    public String hello(Model model){
        model.addAttribute("msg","hello");
        return "hello";   //会被视图解析器解析 WEB-INF/jsp/hello.jsp,也就是跳转到hello.jsp
    }
}
- @Controller相当于之前Spring中- @Component
- @RequestMapping("/hello")该注解可以定义在方法上,也可以定义在类上,用来表示层级关系。
- 返回值会被视图解析器解析
- 创建hello.jsp页面并测试
 
                    
                
 
                
            
         浙公网安备 33010602011771号
浙公网安备 33010602011771号