启动后，日志报下面的错。不过是可以正常访问的。
Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2020-11-08 21:02:22.886 ERROR 6301 --- [           main] o.s.boot.SpringApplication               : Application run failed

org.springframework.context.ApplicationContextException: Failed to start bean 'webServerStartStop'; nested exception is org.springframework.boot.web.server.WebServerException: Unable to start embedded Jetty server
	at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:185) ~[spring-context-5.2.9.RELEASE.jar!/:5.2.9.RELEASE]
	at org.springframework.context.support.DefaultLifecycleProcessor.access$200(DefaultLifecycleProcessor.java:53) ~[spring-context-5.2.9.RELEASE.jar!/:5.2.9.RELEASE]
	at org.springframework.context.support.DefaultLifecycleProcessor$LifecycleGroup.start(DefaultLifecycleProcessor.java:360) ~[spring-context-5.2.9.RELEASE.jar!/:5.2.9.RELEASE]
	at org.springframework.context.support.DefaultLifecycleProcessor.startBeans(DefaultLifecycleProcessor.java:158) ~[spring-context-5.2.9.RELEASE.jar!/:5.2.9.RELEASE]
	at org.springframework.context.support.DefaultLifecycleProcessor.onRefresh(DefaultLifecycleProcessor.java:122) ~[spring-context-5.2.9.RELEASE.jar!/:5.2.9.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:895) ~[spring-context-5.2.9.RELEASE.jar!/:5.2.9.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:554) ~[spring-context-5.2.9.RELEASE.jar!/:5.2.9.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:143) ~[spring-boot-2.3.4.RELEASE.jar!/:2.3.4.RELEASE]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:758) [spring-boot-2.3.4.RELEASE.jar!/:2.3.4.RELEASE]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:750) [spring-boot-2.3.4.RELEASE.jar!/:2.3.4.RELEASE]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) [spring-boot-2.3.4.RELEASE.jar!/:2.3.4.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) [spring-boot-2.3.4.RELEASE.jar!/:2.3.4.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1237) [spring-boot-2.3.4.RELEASE.jar!/:2.3.4.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) [spring-boot-2.3.4.RELEASE.jar!/:2.3.4.RELEASE]
	at run.halo.app.Application.main(Application.java:30) [classes!/:1.4.2]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_241]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_241]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_241]
	at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_241]
	at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:49) [halo-latest.jar:1.4.2]
	at org.springframework.boot.loader.Launcher.launch(Launcher.java:107) [halo-latest.jar:1.4.2]
	at org.springframework.boot.loader.Launcher.launch(Launcher.java:58) [halo-latest.jar:1.4.2]
	at org.springframework.boot.loader.JarLauncher.main(JarLauncher.java:88) [halo-latest.jar:1.4.2]
Caused by: org.springframework.boot.web.server.WebServerException: Unable to start embedded Jetty server
	at org.springframework.boot.web.embedded.jetty.JettyWebServer.start(JettyWebServer.java:194) ~[spring-boot-2.3.4.RELEASE.jar!/:2.3.4.RELEASE]
	at org.springframework.boot.web.servlet.context.WebServerStartStopLifecycle.start(WebServerStartStopLifecycle.java:43) ~[spring-boot-2.3.4.RELEASE.jar!/:2.3.4.RELEASE]
	at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:182) ~[spring-context-5.2.9.RELEASE.jar!/:5.2.9.RELEASE]
	... 22 common frames omitted
Caused by: java.io.IOException: Failed to bind to /0.0.0.0:8090
	at org.eclipse.jetty.server.ServerConnector.openAcceptChannel(ServerConnector.java:349) ~[jetty-server-9.4.31.v20200723.jar!/:9.4.31.v20200723]
	at org.eclipse.jetty.server.ServerConnector.open(ServerConnector.java:310) ~[jetty-server-9.4.31.v20200723.jar!/:9.4.31.v20200723]
	at org.eclipse.jetty.server.AbstractNetworkConnector.doStart(AbstractNetworkConnector.java:80) ~[jetty-server-9.4.31.v20200723.jar!/:9.4.31.v20200723]
	at org.eclipse.jetty.server.ServerConnector.doStart(ServerConnector.java:234) ~[jetty-server-9.4.31.v20200723.jar!/:9.4.31.v20200723]
	at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:72) ~[jetty-util-9.4.31.v20200723.jar!/:9.4.31.v20200723]
	at org.springframework.boot.web.embedded.jetty.JettyWebServer.start(JettyWebServer.java:174) ~[spring-boot-2.3.4.RELEASE.jar!/:2.3.4.RELEASE]
	... 24 common frames omitted
Caused by: java.net.BindException: 地址已在使用
	at sun.nio.ch.Net.bind0(Native Method) ~[na:1.8.0_241]
	at sun.nio.ch.Net.bind(Net.java:433) ~[na:1.8.0_241]
	at sun.nio.ch.Net.bind(Net.java:425) ~[na:1.8.0_241]
	at sun.nio.ch.ServerSocketChannelImpl.bind(ServerSocketChannelImpl.java:223) ~[na:1.8.0_241]
	at sun.nio.ch.ServerSocketAdaptor.bind(ServerSocketAdaptor.java:74) ~[na:1.8.0_241]
	at org.eclipse.jetty.server.ServerConnector.openAcceptChannel(ServerConnector.java:345) ~[jetty-server-9.4.31.v20200723.jar!/:9.4.31.v20200723]
	... 29 common frames omitted