2018年12月29日星期六
体验Spring boot 零配置开发微服务
1.为什么要用Spring boot？
1.1 简单方便、配置少、整合了大多数框架
1.2 适用于微服务搭建，搭建的微服务与Spring clound进行完美融合，因为都是Spring家族
2. Spring boot开发过程
2.1 启动Idea
2.2 创建Maven项目
2.3 引入spring-boot-starter-web核心：Starter for building web, including RESTful, applications using Spring MVC. Uses Tomcat as the default embedded container
2.4 引入spring-boot-starter-test核心：Starter for testing Spring Boot applications with libraries including JUnit, Hamcrest and Mockito
2.5 具体依赖如下：
2.6 <dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<version>2.0.4.RELEASE</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-test -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<version>2.0.4.RELEASE</version>
<scope>test</scope>
</dependency>
2.7 创建Spring boot启动主程序：package com.wuji.boot;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;
@SpringBootApplication
@ComponentScan(basePackages = {"com.wuji.controller"})
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class,args);
}
}
2.8 编写HelloController:
package com.wuji.controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
@RequestMapping("/api")
public class HelloController {
@RequestMapping("/hello")
public String index(){
return "Hello";
}
}
2.9 运行http://localhost:8080/api/hello
2.10 第一次写Spring boot程序运行一般会出现：whitelabel error page 这个错误，是因为默认没有加载控制器包。要在主程序加上@ComponentScan(basePackages = {"com.wuji.controller"})注解
2.11 总结：整个程序只引用了两个核心包2.3，2.4，没有其它配置，就可以启动Restful服务。所以证实了Spring boot基本零配置来开发微服务。