I'm implementing some button on a webpage to learn how to use Vaadin 8 with Java 8 and SpringToolSuite4. I created an empty page with a single button that shows a notification when clicked. The code is working but when running the code with spring boot (v2.7.3) I get the following error:
java.lang.IllegalArgumentException: Component cannot be added inside it's own content
at com.vaadin.ui.AbstractSingleComponentContainer.setContent(AbstractSingleComponentContainer.java:140) ~[vaadin-server-8.5.1.jar:8.5.1]
at com.vaadin.ui.UI.setContent(UI.java:1431) ~[vaadin-server-8.5.1.jar:8.5.1]
at com.vaadin.navigator.Navigator$SingleComponentContainerViewDisplay.showView(Navigator.java:305) ~[vaadin-server-8.5.1.jar:8.5.1]
at com.vaadin.navigator.Navigator.performNavigateTo(Navigator.java:773) ~[vaadin-server-8.5.1.jar:8.5.1]
at com.vaadin.navigator.Navigator.lambda$navigateTo$9a874efd$1(Navigator.java:702) ~[vaadin-server-8.5.1.jar:8.5.1]
at com.vaadin.navigator.Navigator.runAfterLeaveConfirmation(Navigator.java:726) ~[vaadin-server-8.5.1.jar:8.5.1]
at com.vaadin.navigator.Navigator.navigateTo(Navigator.java:701) ~[vaadin-server-8.5.1.jar:8.5.1]
at com.vaadin.navigator.Navigator.navigateTo(Navigator.java:678) ~[vaadin-server-8.5.1.jar:8.5.1]
at com.vaadin.ui.UI.doInit(UI.java:775) ~[vaadin-server-8.5.1.jar:8.5.1]
at com.vaadin.server.communication.UIInitHandler.getBrowserDetailsUI(UIInitHandler.java:218) [vaadin-server-8.5.1.jar:8.5.1]
at com.vaadin.server.communication.UIInitHandler.synchronizedHandleRequest(UIInitHandler.java:76) [vaadin-server-8.5.1.jar:8.5.1]
at com.vaadin.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:40) [vaadin-server-8.5.1.jar:8.5.1]
at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1601) [vaadin-server-8.5.1.jar:8.5.1]
at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:445) [vaadin-server-8.5.1.jar:8.5.1]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:764) [servlet-api.jar:4.0.FR]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227) [catalina.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [catalina.jar:9.0.65]
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:711) [catalina.jar:9.0.65]
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:459) [catalina.jar:9.0.65]
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:353) [catalina.jar:9.0.65]
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:313) [catalina.jar:9.0.65]
at org.springframework.web.servlet.mvc.ServletForwardingController.handleRequestInternal(ServletForwardingController.java:141) [spring-webmvc-5.3.22.jar:5.3.22]
at org.springframework.web.servlet.mvc.AbstractController.handleRequest(AbstractController.java:177) [spring-webmvc-5.3.22.jar:5.3.22]
at org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter.handle(SimpleControllerHandlerAdapter.java:51) [spring-webmvc-5.3.22.jar:5.3.22]
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1070) [spring-webmvc-5.3.22.jar:5.3.22]
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963) [spring-webmvc-5.3.22.jar:5.3.22]
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) [spring-webmvc-5.3.22.jar:5.3.22]
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909) [spring-webmvc-5.3.22.jar:5.3.22]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:681) [servlet-api.jar:4.0.FR]
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) [spring-webmvc-5.3.22.jar:5.3.22]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:764) [servlet-api.jar:4.0.FR]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227) [catalina.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [catalina.jar:9.0.65]
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) [tomcat-websocket.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [catalina.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [catalina.jar:9.0.65]
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) [spring-web-5.3.22.jar:5.3.22]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) [spring-web-5.3.22.jar:5.3.22]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [catalina.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [catalina.jar:9.0.65]
at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) [spring-web-5.3.22.jar:5.3.22]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) [spring-web-5.3.22.jar:5.3.22]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [catalina.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [catalina.jar:9.0.65]
at org.springframework.boot.web.servlet.support.ErrorPageFilter.doFilter(ErrorPageFilter.java:126) [spring-boot-2.7.3.jar:2.7.3]
at org.springframework.boot.web.servlet.support.ErrorPageFilter.access$000(ErrorPageFilter.java:64) [spring-boot-2.7.3.jar:2.7.3]
at org.springframework.boot.web.servlet.support.ErrorPageFilter$1.doFilterInternal(ErrorPageFilter.java:101) [spring-boot-2.7.3.jar:2.7.3]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) [spring-web-5.3.22.jar:5.3.22]
at org.springframework.boot.web.servlet.support.ErrorPageFilter.doFilter(ErrorPageFilter.java:119) [spring-boot-2.7.3.jar:2.7.3]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [catalina.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [catalina.jar:9.0.65]
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) [spring-web-5.3.22.jar:5.3.22]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) [spring-web-5.3.22.jar:5.3.22]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [catalina.jar:9.0.65]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [catalina.jar:9.0.65]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197) [catalina.jar:9.0.65]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) [catalina.jar:9.0.65]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541) [catalina.jar:9.0.65]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135) [catalina.jar:9.0.65]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [catalina.jar:9.0.65]
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:687) [catalina.jar:9.0.65]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) [catalina.jar:9.0.65]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:360) [catalina.jar:9.0.65]
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399) [tomcat-coyote.jar:9.0.65]
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) [tomcat-coyote.jar:9.0.65]
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:890) [tomcat-coyote.jar:9.0.65]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1789) [tomcat-coyote.jar:9.0.65]
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-coyote.jar:9.0.65]
at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) [tomcat-util.jar:9.0.65]
at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) [tomcat-util.jar:9.0.65]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-util.jar:9.0.65]
at java.lang.Thread.run(Thread.java:750) [na:1.8.0_331]
The error shows up also in a tooltip when the mouse is idle on the webpage. Here's the code in my MainUI.java:
* The Class MainUI.
*/
@SpringUI
@Theme("demo")
@SpringViewDisplay
@SpringView(name = "")
public class MainUI extends UI implements View {
@Autowired
OldGenesRepo repo ;
/** The Constant serialVersionUID. */
private static final long serialVersionUID = 1L;
@Override
protected void init(VaadinRequest request) {
try {
final VerticalLayout layout = new VerticalLayout();
Button button = new Button("Click here");
button.setDescription("Try to click me");
button.addClickListener(click ->
{
Notification.show("clicked");
});
layout.addComponent(button);
setContent(layout);
} catch (Exception e) {
System.out.println(e);
}
}
}
What is raising that error and how can I resolve it? Thank you for the help.
CodePudding user response：
You can't implement View in UI. The UI is usually the bottom layer layout and when using Navigator, the Navigator will place view content to the layout managed by it. By default it is the UI. Now in your case it will lead to Navigator attempting to add UI as content of UI, and that wont work.