springboot Protocol handler start failed ：端口占用

org.apache.catalina.LifecycleException: Protocol handler start failed
	at org.apache.catalina.connector.Connector.startInternal(Connector.java:960) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
	at org.apache.catalina.core.StandardService.addConnector(StandardService.java:225) [tomcat-embed-core-9.0.12.jar:9.0.12]
	at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.addPreviouslyRemovedConnectors(TomcatWebServer.java:259) [spring-boot-2.1.0.RELEASE.jar:2.1.0.RELEASE]
	at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.start(TomcatWebServer.java:197) [spring-boot-2.1.0.RELEASE.jar:2.1.0.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.startWebServer(ServletWebServerApplicationContext.java:300) [spring-boot-2.1.0.RELEASE.jar:2.1.0.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.finishRefresh(ServletWebServerApplicationContext.java:162) [spring-boot-2.1.0.RELEASE.jar:2.1.0.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549) [spring-context-5.1.2.RELEASE.jar:5.1.2.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140) [spring-boot-2.1.0.RELEASE.jar:2.1.0.RELEASE]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:775) [spring-boot-2.1.0.RELEASE.jar:2.1.0.RELEASE]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) [spring-boot-2.1.0.RELEASE.jar:2.1.0.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:316) [spring-boot-2.1.0.RELEASE.jar:2.1.0.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1260) [spring-boot-2.1.0.RELEASE.jar:2.1.0.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1248) [spring-boot-2.1.0.RELEASE.jar:2.1.0.RELEASE]
	at com.lujun.manager.ManagerApplication.main(ManagerApplication.java:12) [classes/:na]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_261]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_261]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_261]
	at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_261]
	at com.intellij.rt.execution.CommandLineWrapper.main(CommandLineWrapper.java:63) [idea_rt.jar:na]
Caused by: java.net.BindException: Address already in use: bind
	at sun.nio.ch.Net.bind0(Native Method) ~[na:1.8.0_261]
	at sun.nio.ch.Net.bind(Net.java:444) ~[na:1.8.0_261]
	at sun.nio.ch.Net.bind(Net.java:436) ~[na:1.8.0_261]
	at sun.nio.ch.ServerSocketChannelImpl.bind(ServerSocketChannelImpl.java:225) ~[na:1.8.0_261]
	at sun.nio.ch.ServerSocketAdaptor.bind(ServerSocketAdaptor.java:74) ~[na:1.8.0_261]
	at org.apache.tomcat.util.net.NioEndpoint.initServerSocket(NioEndpoint.java:236) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
	at org.apache.tomcat.util.net.NioEndpoint.bind(NioEndpoint.java:210) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
	at org.apache.tomcat.util.net.AbstractEndpoint.start(AbstractEndpoint.java:1108) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
	at org.apache.coyote.AbstractProtocol.start(AbstractProtocol.java:550) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
	at org.apache.catalina.connector.Connector.startInternal(Connector.java:957) ~[tomcat-embed-core-9.0.12.jar:9.0.12]
	... 19 common frames omitted

2021-04-05 15:00:44.910  INFO 1868 --- [           main] o.apache.catalina.core.StandardService   : Stopping service [Tomcat]
2021-04-05 15:00:44.917  INFO 1868 --- [           main] ConditionEvaluationReportLoggingListener : 

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2021-04-05 15:00:44.921 ERROR 1868 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 

***************************
APPLICATION FAILED TO START
***************************

Description:

The Tomcat connector configured to listen on port 8102 failed to start. The port may already be in use or the connector may be misconfigured.

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