构建Spring MVC 4的HelloWorld实例。
使用以下技术:
- Spring 4.0.6.RELEASE
- Maven 3
- JDK 1.8
如果您已经熟悉maven
使用eclipse 创建项目,请随意跳过第1步。
让我们开始。
步骤1:在Eclipse中创建一个新的Maven webapp项目
Goto File-> New - > Maven Project,
取消选中“使用默认工作区位置”,以防您希望在其他位置创建项目
点击下一步
从选项列表中选择maven web app archetype,单击下一步
提供Group Id,Artifact Id,如上所示的版本,然后单击Finish。更新您的项目
你应该得到如下所示的文件结构
注意:如果您没有在项目结构中看到src/main/java
和src/test/java
文件夹,请转到Project>Properties>Java BuildPath>Libraries,选择/更改为适当的Java版本,单击确定,您应该现在看到这些文件夹。
步骤2:在Maven pom.xml中提供Spring依赖关系
由于它是一个maven项目,所有项目依赖关系都可以配置,pom.xml
并且maven将自动下载所有相应的依赖项。以下是我们项目的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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.demo.springmvc</groupId>
<artifactId>Spring4MVCHelloWorldDemo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>
<properties>
<springframework.version>4.0.6.RELEASE</springframework.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${springframework.version}</version>
</dependency>
<!-- Below declared dependencies are included for the servers who may complain about servlet/jstl missing dependency -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.1.0</version>
</dependency>
<dependency>
<groupId>javax.servlet.jsp</groupId>
<artifactId>javax.servlet.jsp-api</artifactId>
<version>2.3.1</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
</dependencies>
<build>
<pluginManagement>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.2</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</pluginManagement>
<finalName>Spring4MVCHelloWorldDemo</finalName>
</build>
</project>
在maven-compiler-plugin
这里添加了Maven插件来明确指定我们将要使用的java版本。请注意,它也强制eclipse用于项目的jdk版本。如果不存在,eclipse将jdk-version切换回1.5,这是令人讨厌的。所以请添加它在您的项目pom.xml。
步骤3:添加控制器和视图
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
@Controller
@RequestMapping("/")
public class HelloWorldController {
@RequestMapping(method = RequestMethod.GET)
public String sayHello(ModelMap model) {
model.addAttribute("greeting", "Hello World from Spring 4 MVC");
return "welcome";
}
@RequestMapping(value="/helloagain", method = RequestMethod.GET)
public String sayHelloAgain(ModelMap model) {
model.addAttribute("greeting", "Hello World Again, from Spring 4 MVC");
return "welcome";
}
}
在WEB-INF下创建一个名为views的新文件夹,并添加一个简单的JSP页面welcome.jsp(WEB-INF / views / welcome.jsp),在我们的例子中,它将简单地访问从控制器发送的模型值。
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!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>Insert title here</title>
</head>
<body>
Greeting:${greeting}
</body>
</html>
步骤4:创建Spring配置文件
<?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-4.1.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.1.xsd
http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">
<context:component-scan base-package="com.springmvc" />
<mvc:annotation-driven />
<bean
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix">
<value>/WEB-INF/views/</value>
</property>
<property name="suffix">
<value>.jsp</value>
</property>
</bean>
</beans>
步骤5:更新Web配置(web.xml)
文件
<?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" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<display-name>Spring4MVCHelloWorldDemo Web Application</display-name>
<servlet>
<servlet-name>dispatcher</servlet-name>
<servlet-class>
org.springframework.web.servlet.DispatcherServlet
</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring-mvc.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>dispatcher</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>