开发第一个Spring Boot应用

1. 安装jdk 1.6+ ， maven 3.2+

2. 创建maven项目

3. pom.xml修改如下

<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/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>com.example</groupId>
	<artifactId>myproject</artifactId>
	<version>0.0.1-SNAPSHOT</version>

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>1.5.2.RELEASE</version>
	</parent>

	<!-- Additional lines to be added here -->

</project>

   ① spring-boot-starter-parent，提供很多有用的maven默认值

   ② spring-boot-starter-parent，提供了dependencyManagement，添加依赖时可以忽略version

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
</dependencies>

   ① spring-boot-starter-web，开发web应用所需依赖

4. 编写代码

package com.example.myproject;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@EnableAutoConfiguration
public class Example {

	@RequestMapping("/")
	public String home() {
		return "Hello Spring Boot!";
	}

	public static void main(String[] args) {
		SpringApplication.run(Example.class, args);
	}

}

  ① @EnableAutoConfiguration，让Spring Boot根据类路径的jar包依赖为当前项目进行自动配置。

          如：添加了spring-boot-starter-web依赖，会自动添加Tomcat和Spring MVC的依赖，那么Spring Boot会对Tomcat和Spring MVC 进行自动配置。

          如：添加了spring-boot-starter-data-jpa依赖，Spring Boot会自动进行JPA相关的配置。

5. 启动程序

6. 创建可执行jar，pom.xml添加如下

<build>
	<plugins>
		<plugin>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-maven-plugin</artifactId>
		</plugin>
	</plugins>
</build>

7. maven生成jar包，控制台执行jar包

 java -jar myproject-0.0.1-SNAPSHOT.jar 启动成功

8. 完整的pom.xml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/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>com.example</groupId>
	<artifactId>myproject</artifactId>
	<version>0.0.1-SNAPSHOT</version>

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>1.5.2.RELEASE</version>
	</parent>

	<!-- Additional lines to be added here -->

	<properties>
		<java.version>1.8</java.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>

</project>

参考：  Spring Boot Reference Guide