SpringBoot 入门小程序

老规矩，先看项目结构。

SpringBoot 入门小程序

有必要参考前面的博客。maven构建web工程

我们构建好maven工程之后，用pom导入jar包。

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.hust.springboot</groupId>
    <artifactId>SpringBoot</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>war</packaging>

    <name>springboot</name>
    <url>http://maven.apache.org</url>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <!-- Spring Boot 启动父依赖 -->
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.3.3.RELEASE</version>
    </parent>

    <dependencies>

        <!-- Spring Boot web依赖 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

</project>

然后我们需要一个 controller

@RestController告诉Spring以字符串的形式渲染结果，并直接返回给调用者。
@EnableAutoConfiguration 。这个注解告诉Spring Boot根据添加的jar依赖猜测你想如何配置Spring。

HelloController.java

package com.hust.springboot.controller;

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;

import com.hust.springboot.dao.People;

@EnableAutoConfiguration
@RestController
public class HelloController {

    @RequestMapping("/")
    public String sayHello() {
        return "Hello,World!";
    }

    @RequestMapping("/{id}")
    public People getPeople(@PathVariable Integer id) {
        People people = new People();
        people.setId(id);
        people.setAge("20");
        people.setName("yexx");
        return people;
    }
}

我们的main方法通过调用run，将业务委托给了spring Boot的SpringApplication类。SpringApplication将引导我们的应用，启动Spring，相应地启动被自动配置的Tomcat web服务器。
我们需要将 HelloController.class 作为参数传递给run方法来告诉SpringApplication谁是主要的Spring组件。为了暴露任何的命令行参数，args数组也会被传递过去。

Application.java

package com.hust.springboot.application;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

import com.hust.springboot.controller.HelloController;

@SpringBootApplication
public class Application {

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