spring MVC注解之入门
jopen
11年前
第一步:web.xml配置
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5"> <display-name>springmvc-chapter2</display-name> <welcome-file-list> <welcome-file>index.html</welcome-file> <welcome-file>index.htm</welcome-file> <welcome-file>index.jsp</welcome-file> <welcome-file>default.html</welcome-file> <welcome-file>default.htm</welcome-file> <welcome-file>default.jsp</welcome-file> </welcome-file-list> <!-- 配置Servlet的分发以及对springMVC文件的初始路径的引用 --> <servlet> <servlet-name>chapter1</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath*:config/chapter1-servlet.xml</param-value> </init-param> <!-- 标识启动容器时初始化该Servlet --> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>chapter1</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> <!-- 配置系统的编码集合 --> <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>
第二步:springMVC文件的配置,chapter1-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:p="http://www.springframework.org/schema/p" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org /schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd"> <!-- 开启注解,因为每次启动都会调用下面两个类,所以springMVC将其集成到一个配置里面,配置了 这个,下面两个启用注解的类就可以不配置了 --> <mvc:annotation-driven /> <!-- 此配置的作用是用来扫描所有需要注解的类,只有被扫描的类才能使用注解 --> <context:component-scan base-package="cn.javass.chapter2.web.controller"/> <!-- 启用注解,这两个类是使用注解时必须所配置的类,第一个作用是通过url找到类,第二个作用是通过类找到方法--> <!-- <bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping"></bean> <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"></bean> --> <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/WEB-INF/jsp/"></property> <property name="suffix" value=".jsp"></property> </bean>
这个配置文件,如果一些配置报错,那么极有可能是xml文件的头部的那个schema验证有问题,到网上找些正确的就OK啦!
第三步:新建一个jsp页面,hello.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Hello World</title> </head> <body> <c:forEach items="${map }" var="m"> <c:out value="${m.value }">${m.value }</c:out> ${m.key }----------->${m.value } </c:forEach> </body> </html>
第四步:新建一个Controller,HelloWorldController.java
package cn.javass.chapter2.web.controller; import java.util.HashMap; import java.util.Map; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.servlet.ModelAndView; import org.springframework.stereotype.Controller; @Controller public class HelloWorldController{ @RequestMapping(value="/hello",method=RequestMethod.GET) public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception { // 1、收集参数、验证参数 // 2、绑定参数到命令对象n // 3、将命令对象传入业务对象进行业务处理 // 4、选择下一个页面 /*ModelAndView mv = new ModelAndView(); // 添加模型数据 可以是任意的POJO对象 mv.addObject("message", "This is the first test Hello World!"); // 设置逻辑视图名,视图解析器会根据该名字解析到具体的视图页面 mv.setViewName("hello");*/ System.out.println("进入此方法!"); Map<String,Object> map = new HashMap<String, Object>(); map.put("map1", "springMVC测试1"); map.put("map2", "springMVC测试2"); map.put("map3", "springMVC测试3"); return new ModelAndView("/hello","map",map); } }
@Controller注解写了之后(必须),Spring都会把它当做需要注入的Bean加载在上下文中,从而代替之前配置文件的功能;@RequestMapping(value=“/hello”,method=RequestMethod.GET),value代表访问路径,method代表请求方式,此处用GET请求,换成POST请求也可以。最后返回到hello.jsp视图。
启动tomcat,访问http://localhost:8080/springmvc-chapter2/hello,结果如下:
至此,一个简单的springMVC注解就完成了!