Spring Boot入门

1.1. helloWorld

1. 登陆地址：https://start.spring.io/

2. 选择相应组建，下载文件

3. 然后导入ideal中

 

4. 开发hello world

创建包com.example.demo.controller

在包com.example.demo.controller下面新建HelloWorldController.java

@RestController

public class HelloWorldController {

    @RequestMapping("/hello")

    public String index()

    {

        return "Hellow World!";

    }

}

这时候发现不识别注解@RestController，按照ideal提示点击以后，会在pom.xml中新增以下内容：

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

5. 启动程序

 

从浏览器端访问http://127.0.0.1:8080/hello

6. 手动启动

手动构建：mvn dependency:tree //在pom.xml目录下

手动启动:  mvn spring-boot:run

7. 打包发布

确认在pox.xml中包含：

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

打jar包：mvn package //在pom.xml目录下

打包启动:$javar -jar ./target/demo-0.0.1-SNAPSHOT.jar

debug启动：$ java -jar myproject-0.0.1-SNAPSHOT.jar --debug

1.2. 推荐目录结构

com

 +- example

     +- myapplication

         +- Application.java

         |

         +- customer

         |   +- Customer.java

         |   +- CustomerController.java

         |   +- CustomerService.java

         |   +- CustomerRepository.java

         |

         +- order

             +- Order.java

             +- OrderController.java

             +- OrderService.java

             +- OrderRepository.java

1.3. Spring Bean和Dependent Injection

For simplicity, we often find that using @ComponentScan (to find your beans) and using @Autowired (to do constructor injection) works well.

If you structure your code as suggested above (locating your application class in a root package), you can add @ComponentScan without any arguments. All of your application components (@Component, @Service, @Repository, @Controller etc.) are automatically registered as Spring Beans

1.4. 静态页面目录

 

点击浏览器，访问：http://127.0.0.1:8080/index.html，访问成功。

错误页面目录：

src/

 +- main/

     +- java/

     |   + <source code>

     +- resources/

         +- static/

             +- error/

             |   +- 404.html

             +- index.html

点击浏览器，访问：http://127.0.0.1:8080/index2.html，index2是一个不存在的资源。访问后会弹出404.html成功。

1.5. 内置tomcat端口配置

server.port=8089