spring boot最小web项目

创建一个spring boot最小web项目，除了一个pom文件配置，不需要任何其他xml之类的配置了

这源于spring boot的一个核心价值，即约定大于配置

开发人员不需要告诉应用，这个地方要如何如何，那个地方要如何如何，一切尽在不言中，正如那个名言——你懂的

你只需要给出很少量的暗示，剩下的就交给spring boot去处理吧

但是任何事物都有两面，spring boot也是一把双刃剑，你懂的，这其中的深刻含义，意味着spring boot会按照它的习惯，或者说是默认方式去替你配置本应该由你来完成的一系列操作，一旦这个默认配置不是你所想要的，你还是得亲自上手去干预，这时候你会发现程序似乎正在脱离你的掌控，你的权力正在削弱

但也必须得承认，spring boot在它的领域确实做得很好，它可以帮助你在数分钟之内成功运行一个最小web项目。

唯一的pom配置如下

<?xml version="1.0" encoding="UTF-8"?><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>spring-boot-helloworld</groupId>    <artifactId>spring-boot-helloworld</artifactId>    <version>1.0-SNAPSHOT</version>    <!-- Inherit defaults from Spring Boot -->    <parent>        <groupId>org.springframework.boot</groupId>        <artifactId>spring-boot-starter-parent</artifactId>        <version>0.5.0.BUILD-SNAPSHOT</version>    </parent>    <!-- Add typical dependencies for a web application -->    <dependencies>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter-web</artifactId>        </dependency>    </dependencies>    <!-- Package as an executable JAR -->    <build>        <plugins>            <plugin>                <groupId>org.springframework.boot</groupId>                <artifactId>spring-boot-maven-plugin</artifactId>            </plugin>        </plugins>    </build>    <!-- Allow access to Spring milestones and snapshots -->    <!-- (you don't need this if you are using anything after 0.5.0.RELEASE) -->    <repositories>        <repository>            <id>spring-snapshots</id>            <url>http://repo.spring.io/snapshot</url>            <snapshots><enabled>true</enabled></snapshots>        </repository>        <repository>            <id>spring-milestones</id>            <url>http://repo.spring.io/milestone</url>            <snapshots><enabled>true</enabled></snapshots>        </repository>    </repositories>    <pluginRepositories>        <pluginRepository>            <id>spring-snapshots</id>            <url>http://repo.spring.io/snapshot</url>        </pluginRepository>        <pluginRepository>            <id>spring-milestones</id>            <url>http://repo.spring.io/milestone</url>        </pluginRepository>    </pluginRepositories>    </project>

在加上三个java文件

1.main函数

package org.spring.my.boot;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.EnableAutoConfiguration;import org.springframework.boot.builder.SpringApplicationBuilder;import org.springframework.boot.context.embedded.ConfigurableEmbeddedServletContainerFactory;import org.springframework.boot.context.embedded.EmbeddedServletContainerCustomizer;import org.springframework.boot.web.SpringBootServletInitializer;import org.springframework.context.annotation.ComponentScan;import org.springframework.context.annotation.Configuration;@EnableAutoConfiguration@Configuration@ComponentScanpublic class Application extends SpringBootServletInitializer implementsEmbeddedServletContainerCustomizer {@Overrideprotected SpringApplicationBuilder configure(SpringApplicationBuilder builder) {return builder.sources(Application.class);}public static void main(String[] args) {SpringApplication.run(Application.class, args);}/* * (non-Javadoc) 通过实现EmbeddedServletContainerCustomizer接口设置Tomcat服务端口 *  * @see * org.springframework.boot.context.embedded.EmbeddedServletContainerCustomizer * #customize(org.springframework.boot.context.embedded. * ConfigurableEmbeddedServletContainerFactory) */public void customize(ConfigurableEmbeddedServletContainerFactory arg0) {// TODO Auto-generated method stubarg0.setPort(8081);}}

2.控制器

<pre name="code" class="java">package org.spring.my.boot.controller;import org.spring.my.boot.entity.User;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.EnableAutoConfiguration;import org.springframework.web.bind.annotation.PathVariable;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RestController;/** */@EnableAutoConfiguration@RestController@RequestMapping("/user")public class UserController {@RequestMapping("/{id}")private User view(@PathVariable("id") Long id) {User user = new User();user.setId(id);user.setName("xxx");return user;}public static void main(String[] args) {SpringApplication.run(UserController.class);}}

3.实体

<pre name="code" class="java">package org.spring.my.boot.entity;import java.io.Serializable;/** */public class User implements Serializable {/** *  */private static final long serialVersionUID = 1L;private Long id;private String name;public Long getId() {return id;}public void setId(Long id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}}

运行main函数，spring boot会自动将服务以Restful风格的web接口发布在嵌入式Tomcat服务器的8081端口

在浏览器中输入http://localhost:8081/user/1，即可得到实体以json格式返回