入门案例

需求：

环境搭建

Idea创建Maven工程，选择webapp

maven项目创建时，可以加一组键值对archetypeCatalog : internal，解决加载慢的问题

建立的工程目录是不全的，在src/main下手动加上java、resource文件夹，并右键Mark Directory as设置为源码、资源文件夹

pom.xml

<properties>
  <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  <!-- 编译版本改成1.8 -->
  <maven.compiler.source>1.8</maven.compiler.source>
  <maven.compiler.target>1.8</maven.compiler.target>
  <!-- spring版本锁定，下面直接引用 -->
  <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>

web.xml

配置前端控制器（servlet）

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

  <servlet>
    <servlet-name>dispatcherServlet</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <!-- 加载springmvc的配置文件 -->
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:springmvc.xml</param-value>
    </init-param>
    <!-- 启动服务器时加载 -->
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>dispatcherServlet</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

</web-app>

springmvc的配置文件

在resources中New->XML Configuration File->Spring Config

名称没有要求，这里叫springmvc

导入名称空间，开启注解扫描

<?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">

    <!-- 开启注解扫描 -->
    <context:component-scan base-package="com.test"/>
  
  	<!-- 视图解析器 -->
    <bean id="internalResourceViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <!-- 配置文件目录 -->
        <property name="prefix" value="/WEB-INF/pages"></property>
        <!-- 配置后缀名 -->
        <property name="suffix" value=".jsp"></property>
    </bean>

  	<!-- 开启SpringMVC框架注解支持 -->
    <mvc:annotation-driven></mvc:annotation-driven>
  
</beans>

部署服务器

Add Configuration

加一个本地的Tomcat

在Deployment中添加

代码编写

index.jsp

默认自带的index.jsp没有头文件信息，中文可能会有乱码问题

可以删了重新创建一个

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
    <h1>入门程序</h1>
    <a href="hello">点这里</a>
</body>
</html>

HelloController.java

package com.test.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
public class HelloController {

    @RequestMapping(path="/hello")
    public String sayHello(){
        System.out.println("Hello Spring");
        return "success";
    }

}