SpringBoot随记

Aurora

Spring

375 words

1 min

发布于：May 22, 2020

次浏览

SpringBoot

开始

延迟初始化

bean不会一开始就初始化，启动快，但是相应的bean配置错误不会在一开始显现出来

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spring:
  main:
    lazy-initialization: true

元数据支持

引入configuration-processor依赖，在yaml中配置也会有相应提示

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-configuration-processor</artifactId>
    <optional>true</optional>
</dependency>

会生成metadata.json

配置属性

Javabean属性绑定和Constructor绑定

yaml

acme:
  enabled: false
  remote-address: 192.168.45.113
  security:
    username: root
    password: root
    roles: [11,22,33]

松散绑定

了解一下

JSR-303属性校验

如果存在内部类，在内部类加上@Valid注解才会生效

@ConfigurationProperties vs. @Value

特征	`@ConfigurationProperties`	`@Value`
松散绑定	Yes	Limited (see note below)有限支持
元数据支持	Yes	No
`SpEL` 表达式	No	Yes
复杂类型绑定	Yes	No
JSR-303属性校验	Yes	No

Async

@Service
public class AsyncService {

    @Async // 异步任务
    public void hello(){
        try {
            Thread.sleep(3000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        System.out.println("数据处理完成！");
    }
}

@Controller
public class AsyncController {

    @Autowired
    private AsyncService asyncService;

    @ResponseBody
    @GetMapping("hello")
    public String hello() {
        asyncService.hello();
        return "OK";
    }
}

@EnableAsync // 开启异步功能
@SpringBootApplication
public class SpringbootAsyncMailScheduledApplication {

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

}

Schedule

@Service
public class ScheduledService {

    // 定时任务 cron表达式（5秒执行一次）
    @Scheduled(cron = "0/5 * * * * *")
    public void printDate(){
        System.out.println(new Date());
    }
}

@EnableScheduling // 开启定时任务
@SpringBootApplication
public class SpringbootAsyncMailScheduledApplication {

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

}