springboot bootstrap.yml和application.yml
bootstrap.yml在application.yml之前加载，一般在spring cloud使用配置中心的时候使用；
bootstrap.yml同名属性会被application.yml覆盖；
application.yml在application.properties之前加载，同名属性会被application.properties覆盖
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示例
导入jar包，使bootstrap.yml得配置生效
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-context</artifactId>
<version>2.2.0.RELEASE</version>
</dependency>
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bootstrap.yml
server:
port: 8081启动应用，控制台输出
2019-12-20 11:03:50.672 INFO 20380 --- [ main] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2019-12-20 11:03:50.676 INFO 20380 --- [ main] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 1370 ms
2019-12-20 11:03:50.936 INFO 20380 --- [ main] o.s.s.concurrent.ThreadPoolTaskExecutor : Initializing ExecutorService 'applicationTaskExecutor'
2019-12-20 11:03:51.289 INFO 20380 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8081 (http) with context path ''
2019-12-20 11:03:51.296 INFO 20380 --- [ main] com.example.demo.DemoApplication : Started DemoApplication in 3.264 seconds (JVM running for 6.268)
应用监听端口为8081，bootstrap.yml生效
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添加application.yml
server:
port: 8082启动应用，控制台输出
2019-12-20 11:07:33.062 INFO 22148 --- [ main] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2019-12-20 11:07:33.062 INFO 22148 --- [ main] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 739 ms
2019-12-20 11:07:33.179 INFO 22148 --- [ main] o.s.s.concurrent.ThreadPoolTaskExecutor : Initializing ExecutorService 'applicationTaskExecutor'
2019-12-20 11:07:33.374 INFO 22148 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8082 (http) with context path ''
2019-12-20 11:07:33.377 INFO 22148 --- [ main] com.example.demo.DemoApplication : Started DemoApplication in 2.011 seconds (JVM running for 3.696)
应用监听端口为8082，application.yml覆盖bootstrap.yml的端口配置
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添加application.properties
server.port=8083启动应用，控制台输出
2019-12-20 11:11:04.004 INFO 608 --- [ main] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2019-12-20 11:11:04.004 INFO 608 --- [ main] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 844 ms
2019-12-20 11:11:04.149 INFO 608 --- [ main] o.s.s.concurrent.ThreadPoolTaskExecutor : Initializing ExecutorService 'applicationTaskExecutor'
2019-12-20 11:11:04.316 INFO 608 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8083 (http) with context path ''
2019-12-20 11:11:04.320 INFO 608 --- [ main] com.example.demo.DemoApplication : Started DemoApplication in 2.018 seconds (JVM running for 3.692)
应用监听端口为8083，application.yml覆盖前面的配置信息
