Spring Boot Application in Docker Container throws java.lang.UnsatisfiedLinkError

I am running a spring boot application in a docker container. Calling PDDocument of Apache PDFBox throws following error:
In PDFBox i try to read in a pdf document to read out lines of this pdf

java.lang.UnsatisfiedLinkError: /usr/local/openjdk-8/jre/lib/amd64/libawt_xawt.so: libXext.so.6: cannot open shared object file: No such file or directory
        at java.lang.ClassLoader$NativeLibrary.load(Native Method) ~[na:1.8.0_242]
        at java.lang.ClassLoader.loadLibrary0(ClassLoader.java:1946) ~[na:1.8.0_242]
        at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1828) ~[na:1.8.0_242]
        at java.lang.Runtime.load0(Runtime.java:810) ~[na:1.8.0_242]
        at java.lang.System.load(System.java:1088) ~[na:1.8.0_242]
        at java.lang.ClassLoader$NativeLibrary.load(Native Method) ~[na:1.8.0_242]
        at java.lang.ClassLoader.loadLibrary0(ClassLoader.java:1946) ~[na:1.8.0_242]
        at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1849) ~[na:1.8.0_242]
        at java.lang.Runtime.loadLibrary0(Runtime.java:871) ~[na:1.8.0_242]
        at java.lang.System.loadLibrary(System.java:1124) ~[na:1.8.0_242]
        at java.awt.image.ColorModel$1.run(ColorModel.java:209) ~[na:1.8.0_242]
        at java.awt.image.ColorModel$1.run(ColorModel.java:207) ~[na:1.8.0_242]
        at java.security.AccessController.doPrivileged(Native Method) ~[na:1.8.0_242]
        at java.awt.image.ColorModel.loadLibraries(ColorModel.java:206) ~[na:1.8.0_242]
        at java.awt.image.ColorModel.<clinit>(ColorModel.java:219) ~[na:1.8.0_242]
        at java.awt.image.Raster.<clinit>(Raster.java:172) ~[na:1.8.0_242]
        at org.apache.pdfbox.pdmodel.PDDocument.<clinit>(PDDocument.java:107) ~[pdfbox-2.0.19.jar!/:2.0.19]
        at com.admintool.controller.UploadController.updateDocument(UploadController.java:158) ~[classes!/:0.0.1-SNAPSHOT]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_242]
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_242]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_242]
        at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_242]
        at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:106) ~[spring-webmvc-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:879) ~[spring-webmvc-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793) ~[spring-webmvc-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040) ~[spring-webmvc-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943) ~[spring-webmvc-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909) ~[spring-webmvc-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:660) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.springframework.security.oauth2.client.filter.OAuth2ClientContextFilter.doFilter(OAuth2ClientContextFilter.java:60) ~[spring-security-oauth2-2.3.8.RELEASE.jar!/:na]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:320) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:126) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:90) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:118) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:137) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:158) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.authentication.ui.DefaultLogoutPageGeneratingFilter.doFilterInternal(DefaultLogoutPageGeneratingFilter.java:52) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.authentication.ui.DefaultLoginPageGeneratingFilter.doFilter(DefaultLoginPageGeneratingFilter.java:216) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:200) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.oauth2.client.web.OAuth2AuthorizationRequestRedirectFilter.doFilterInternal(OAuth2AuthorizationRequestRedirectFilter.java:160) ~[spring-security-oauth2-client-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:116) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.header.HeaderWriterFilter.doHeadersAfter(HeaderWriterFilter.java:92) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:77) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:215) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:178) ~[spring-security-web-5.2.2.RELEASE.jar!/:5.2.2.RELEASE]
        at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:358) ~[spring-web-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:271) ~[spring-web-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.4.RELEASE.jar!/:5.2.4.RELEASE]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202) ~[tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541) [tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) [tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) [tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) [tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:367) [tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) [tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868) [tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1639) [tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_242]
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_242]
        at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-9.0.31.jar!/:9.0.31]
        at java.lang.Thread.run(Thread.java:748) [na:1.8.0_242]

Dockerfile

FROM openjdk:12
ADD target/admin-tool.jar admin-tool.jar
EXPOSE 7890
ENTRYPOINT ["java", "-jar", "admin-tool.jar"]

I tried to add RUN sudo yum install libXext.i686 to my dockerfile but there is a [Y/N] point where the command exit with code 1.
So I should install it, but don’t know why.

Thanks for help

Source: StackOverflow