后台架构实战——Spring框架搭建

本文为java后台实战的开篇——Spring框架搭建，项目采用maven管理，废话不多说直接进入正题。
首先开发eclipse新建maven工程【File->New->Others...->Maven->Maven Project】



点击Next



直接点击Next



选择Artifact Id为maven-archetype-webapp然后点击Next



填写Group Id，Artifact Id后点击Finish，这样一个基础的Maven管理的webapp就创建成功了



Maven默认采用的是J2SE-1.5，我本地安装的是1.8，为了却换到1.8可以通过以下步骤完成：
右击项目选择Properties



选择Project Facets，右侧可以看到Java选项，把相应的版本改为1.8



点击【Apply->Ok】完成设置



接下来在pom.xml配置Sping依赖包（Spring框架文档http://docs.spring.io/spring/docs/current/spring-framework-reference/htmlsingle/）
我们先要导入Spring的核心模块
spring-core, spring-beans, spring-context, spring-context-support
然后导入Spring web模块
spring-web, spring-webmvc
pom.xml最后的文件如下

<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.xt</groupId>
<artifactId>tutorial</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>tutorial 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>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-core -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-beans -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-context-support -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-web -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring.version}</version>
</dependency>

</dependencies>
<build>
<finalName>tutorial</finalName>
</build>
<properties>
<spring.version>4.3.2.RELEASE</spring.version>
</properties>
</project>

配置web.xml

<!DOCTYPE web-app PUBLIC
"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring-context.xml</param-value>
</context-param>

<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

<servlet>
<servlet-name>dispatcher</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value></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>

在WEB-INF下面添加spring-context.xml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: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.or bef8
g/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">
<context:component-scan base-package="com.xt.tutorial" />
<mvc:annotation-driven enable-matrix-variables="true" />
</beans>

新建IndexController



IndexController.java内容如下

package com.xt.tutorial.v1.controllers;

import java.util.HashMap;
import java.util.Map;

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

@Controller
@RequestMapping("/index")
public class IndexController {
<span style="white-space:pre">	</span>@GetMapping
<span style="white-space:pre">	</span>@ResponseBody
<span style="white-space:pre">	</span>public Map<String, Object> index() {
<span style="white-space:pre">		</span>Map<String, Object> response = new HashMap<>();
<span style="white-space:pre">		</span>response.put("code", 200);
<span style="white-space:pre">		</span>response.put("message", "Ok");
<span style="white-space:pre">		</span>response.put("data", new HashMap<String, String>());
<span style="white-space:pre">		</span>return response;
<span style="white-space:pre">	</span>}
}

为了能让工程跑起来，我们安装一个jetty的maven插件，在pom.xml添加如下代码

<build>
<finalName>tutorial</finalName>
<!-- jetty:run -->
<plugins>
<plugin>
<groupId>org.mortbay.jetty</groupId>
<artifactId>jetty-maven-plugin</artifactId>
<version>8.1.16.v20140903</version>
</plugin>
</plugins>
</build>

最终完整的pom.xml如下

<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.xt</groupId>
<artifactId>tutorial</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>tutorial 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>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-core -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-beans -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-context-support -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-web -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring.version}</version>
</dependency>

</dependencies>

<build>
<finalName>tutorial</finalName>
<!-- jetty:run -->
<plugins>
<plugin>
<groupId>org.mortbay.jetty</groupId>
<artifactId>jetty-maven-plugin</artifactId>
<version>8.1.16.v20140903</version>
</plugin>
</plugins>
</build>

<properties>
<spring.version>4.3.2.RELEASE</spring.version>
</properties>
</project>

右击工程【Run As->Maven build】



Goals:install jetty:run
点击【Apply->Run】这样基础的spring框架就跑起来了



在浏览器中输入localhost:8080/index，会发现以下错误



这个错误很明显说我们没有配置相应返回类型的converter，因为我们需要反悔json数据所以我们直接在项目中引入jackson，在pom.xml中添加如下代码

<!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind -->
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>${jackson.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core -->
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>${jackson.version}</version>
</dependency>

完整的pom.xml如下

<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.xt</groupId>
<artifactId>tutorial</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>tutorial 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>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-core -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-beans -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-context-support -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-web -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind -->
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>${jackson.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core -->
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>${jackson.version}</version>
</dependency>

</dependencies>

<build>
<finalName>tutorial</finalName>
<!-- jetty:run -->
<plugins>
<plugin>
<groupId>org.mortbay.jetty</groupId>
<artifactId>jetty-maven-plugin</artifactId>
<version>8.1.16.v20140903</version>
</plugin>
</plugins>
</build>

<properties>
<spring.version>4.3.2.RELEASE</spring.version>
<jackson.version>2.8.3</jackson.version>
</properties>
</project>

右击项目【Run As->Maven build】重新运行，在浏览器中输入localhost:8080\index



这样一个spring web基础工程就搭建完成了
工程完整地址：https://github.com/imchenglibin/spring-web-tutorial