springMVC demo搭建

1、使用idea新建一个基于maven的web项目，参考 http://www.cnblogs.com/winkey4986/p/5279820.html

2、采取了比较偷懒的配置方法，只配置了一个DispatcherServlet，注意区别同时配置DispatcherServlet和ContextLoaderListener 

    （从长远考虑是需要同时配置的，DispatcherServelet中主要扫描Controller，参考 http://www.cnblogs.com/winkey4986/p/5280138.html）

3、先配置pom.xml

<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/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.icebean</groupId>
  <artifactId>chicken</artifactId>
  <packaging>war</packaging>
  <version>1.0-SNAPSHOT</version>
  <name>chicken Maven Webapp</name>
  <url>http://maven.apache.org</url>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
    <!--Spring-->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>4.2.4.RELEASE</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context</artifactId>
      <version>4.2.4.RELEASE</version>
    </dependency>
  </dependencies>

  <build>
    <plugins>
    <!--jetty-->
      <plugin>
        <groupId>org.mortbay.jetty</groupId>
        <artifactId>maven-jetty-plugin</artifactId>
        <version>6.1.6</version>
        <configuration>
          <connectors>
            <connector implementation="org.mortbay.jetty.nio.SelectChannelConnector">
              <port>9999</port>
              <maxIdleTime>60000</maxIdleTime>
            </connector>
          </connectors>
        </configuration>
      </plugin>
    </plugins>
    <finalName>chicken</finalName>
  </build>
</project>
    

pom中配置了 spring-webmvc、spring-context，另外插件中配置了jetty web容器，指定端口为9999

4、“偷懒配法”web.xml

<?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">

    <display-name>chicken</display-name>
    <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:applicationContext.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>
    <welcome-file-list>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>
</web-app>

对于web.xml中指定的spring配置文件applicationContext.xml（此文件放在resources中）配置

<?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="com.icebean"/>
</beans>

5、ok。配置文件好了，接下来是代码：

package com.icebean.demo;

/**
 * Created by ***on 2016/3/15.
 */
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")
    @ResponseBody
    public String test() {
        return "hello, world! This com from spring!";
    }

}

然后运行maven中的jetty插件，访问地址：http://localhost:9999/chicken/hello 搞定

总结一下：

1 创建一个标准的基于maven的web项目

2 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

3 一个web.xml文件，配置了listener和servlet（可以只有一个DispatcherServelet）
4 两个spring相关的文件，applicationContext.xml和servletName-servlet.xml（可以只有一个applicationContext）
5 一个controller文件，配置了拦截的url处理代码