【一步一步学习springboot】springboot起步

eclipse 初始化 spring 环境

• jdk

  • 略

• maven

  • 略

• 安装spring插件

  • Eclipse Marketplace中搜索spring tools，安装sts插件。

    

• 将eclipse更改为spring视窗模式。

  • Window->Perspective->Open Perspective->Other...选择spring即可。

• 创建第一个springboot项目

  • New Spring Starter Project

    

  • 选择web

    

  • finish

  • 【错误解决】：出现org.apache.maven.archiver.MavenArchiver.getManifest错误

    • Help——>Install New SoftWare
    • Add https://otto.takari.io/content/sites/m2e.extras/m2eclipse-mavenarchiver/0.17.2/N/LATEST/
    • 按照安装提示，一直next，重启eclipse之后，执行maven-update project。

  • pom文件内容为：

    <?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>com.example</groupId>
    	<artifactId>demo</artifactId>
    	<version>0.0.1-SNAPSHOT</version>
    	<packaging>jar</packaging>
    
    	<name>demo</name>
    	<description>Demo project for Spring Boot</description>
    
    	<parent>
    		<groupId>org.springframework.boot</groupId>
    		<artifactId>spring-boot-starter-parent</artifactId>
    		<version>2.0.4.RELEASE</version>
    		<relativePath/> <!-- lookup parent from repository -->
    	</parent>
    
    	<properties>
    		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    		<java.version>1.8</java.version>
    	</properties>
    
    	<dependencies>
    		<dependency>
    			<groupId>org.springframework.boot</groupId>
    			<artifactId>spring-boot-starter-web</artifactId>
    		</dependency>
    
    		<dependency>
    			<groupId>org.springframework.boot</groupId>
    			<artifactId>spring-boot-starter-test</artifactId>
    			<scope>test</scope>
    		</dependency>
    	</dependencies>
    
    	<build>
    		<plugins>
    			<plugin>
    				<groupId>org.springframework.boot</groupId>
    				<artifactId>spring-boot-maven-plugin</artifactId>
    			</plugin>
    		</plugins>
    	</build>
    </project>
    

​ 当前springboot2有很多坑，不建议使用，直接使用1.5.15-RELEASE版本即可

• 配置文件格式建议使用yml格式。

  server:
    port: 8081
    context-path: /demo
      
  person:
    age: 12
    name: xxx
  
  

• 使用@ConfigurationProperties获取配置。

  @Component
  @ConfigurationProperties(prefix="person")
  public class PersonProperties {
  	private String name;
  	private int age;
  	
  	public String getName() {
  		return name;
  	}
  	public void setName(String name) {
  		this.name = name;
  	}
  	public int getAge() {
  		return age;
  	}
  	public void setAge(int age) {
  		this.age = age;
  	}
  	@Override
  	public String toString() {
  		return "I am " + name + ", age : " + age;
  	}
  }
  

• controller一定要跟启动类在同级或者下级的文件夹中。如果不在需要@ComponentScan指定扫描路径。

  @SpringBootApplication
  @ComponentScan(value={"com.example.demo", "com.example.controller"})
  public class DemoApplication {
  
  	public static void main(String[] args) {
  		SpringApplication.run(DemoApplication.class, args);
  	}
  }