java.util.NoSuchElementException when a Validator throws an InvalidInputException for the "comment" field

2018-10-01 13:06:12,646 http-nio-2990-exec-8 ERROR admin 786x31906x1 1zl5ea 0:0:0:0:0:0:0:1 /secure/CommentAssignIssue.jspa [webwork.util.ValueStack] query="/tabsWithErrors" {[id="null" type="5" values=""]} {[id="tabsWithErrors" type="8" values=""]}
java.lang.reflect.InvocationTargetException
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at webwork.util.InjectionUtils$DefaultInjectionImpl.invoke(InjectionUtils.java:70)
	at webwork.util.InjectionUtils.invoke(InjectionUtils.java:56)
	at webwork.util.ValueStack.findValue(ValueStack.java:417)
	at webwork.util.ValueStack.findValue(ValueStack.java:216)
	at webwork.view.taglib.WebWorkBodyTagSupport.findValue(WebWorkBodyTagSupport.java:62)
	at webwork.view.taglib.ParamTag.doEndTag(ParamTag.java:59)
	at jsp.secure.views.issue.commentassignissue_jsp._jspx_meth_ww_005fparam_005f3(commentassignissue_jsp.java:1876)
	at jsp.secure.views.issue.commentassignissue_jsp._jspx_meth_ww_005fcomponent_005f0(commentassignissue_jsp.java:1772)
	at jsp.secure.views.issue.commentassignissue_jsp._jspx_meth_page_005fapplyDecorator_005f0(commentassignissue_jsp.java:609)
	at jsp.secure.views.issue.commentassignissue_jsp._jspx_meth_ww_005fif_005f1(commentassignissue_jsp.java:528)
	at jsp.secure.views.issue.commentassignissue_jsp._jspService(commentassignissue_jsp.java:171)
	at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	... 48 filtered
	at com.atlassian.servicedesk.internal.web.ExternalCustomerLockoutFilter.doFilter(ExternalCustomerLockoutFilter.java:56)
	... 4 filtered
	at com.atlassian.web.servlet.plugin.request.RedirectInterceptingFilter.doFilter(RedirectInterceptingFilter.java:21)
	... 45 filtered
	at com.atlassian.jira.security.JiraSecurityFilter.lambda$doFilter$0(JiraSecurityFilter.java:66)
	... 1 filtered
	at com.atlassian.jira.security.JiraSecurityFilter.doFilter(JiraSecurityFilter.java:64)
	... 20 filtered
	at com.atlassian.jira.servermetrics.CorrelationIdPopulatorFilter.doFilter(CorrelationIdPopulatorFilter.java:30)
	... 5 filtered
	at com.atlassian.servicedesk.internal.web.CustomerContextSettingFilter.doFilter(CustomerContextSettingFilter.java:116)
	... 11 filtered
	at com.atlassian.jira.servermetrics.MetricsCollectorFilter.doFilter(MetricsCollectorFilter.java:25)
	... 11 filtered
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
	... 48 filtered
	at com.atlassian.servicedesk.internal.web.ExternalCustomerLockoutFilter.doFilter(ExternalCustomerLockoutFilter.java:56)
	... 4 filtered
	at com.atlassian.greenhopper.jira.filters.ClassicBoardRouter.doFilter(ClassicBoardRouter.java:62)
	... 12 filtered
	at com.atlassian.web.servlet.plugin.request.RedirectInterceptingFilter.doFilter(RedirectInterceptingFilter.java:21)
	... 24 filtered
	at com.atlassian.labs.httpservice.resource.ResourceFilter.doFilter(ResourceFilter.java:59)
	... 37 filtered
	at com.atlassian.jira.security.JiraSecurityFilter.lambda$doFilter$0(JiraSecurityFilter.java:66)
	... 1 filtered
	at com.atlassian.jira.security.JiraSecurityFilter.doFilter(JiraSecurityFilter.java:64)
	... 39 filtered
	at com.atlassian.jira.servermetrics.CorrelationIdPopulatorFilter.doFilter(CorrelationIdPopulatorFilter.java:30)
	... 5 filtered
	at com.atlassian.servicedesk.internal.web.CustomerContextSettingFilter.lambda$invokeFilterChain$0(CustomerContextSettingFilter.java:181)
	at com.atlassian.servicedesk.internal.api.util.context.ReentrantThreadLocalBasedCodeContext.rteInvoke(ReentrantThreadLocalBasedCodeContext.java:137)
	at com.atlassian.servicedesk.internal.api.util.context.ReentrantThreadLocalBasedCodeContext.runOutOfContext(ReentrantThreadLocalBasedCodeContext.java:90)
	at com.atlassian.servicedesk.internal.utils.context.CustomerContextServiceImpl.runOutOfCustomerContext(CustomerContextServiceImpl.java:47)
	at com.atlassian.servicedesk.internal.web.CustomerContextSettingFilter.outOfCustomerContext(CustomerContextSettingFilter.java:174)
	at com.atlassian.servicedesk.internal.web.CustomerContextSettingFilter.doFilterImpl(CustomerContextSettingFilter.java:130)
	at com.atlassian.servicedesk.internal.web.CustomerContextSettingFilter.doFilter(CustomerContextSettingFilter.java:121)
	... 4 filtered
	at com.atlassian.fastdev.AutoReloadFilter.doFilter(AutoReloadFilter.java:63)
	... 3 filtered
	at com.atlassian.jwt.internal.servlet.JwtAuthFilter.doFilter(JwtAuthFilter.java:32)
	... 8 filtered
	at com.atlassian.web.servlet.plugin.request.RedirectInterceptingFilter.doFilter(RedirectInterceptingFilter.java:21)
	... 4 filtered
	at com.atlassian.web.servlet.plugin.LocationCleanerFilter.doFilter(LocationCleanerFilter.java:36)
	... 26 filtered
	at com.atlassian.jira.servermetrics.MetricsCollectorFilter.doFilter(MetricsCollectorFilter.java:25)
	... 22 filtered
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:748)
Caused by: java.util.NoSuchElementException
	at java.util.TreeMap.key(TreeMap.java:1327)
	at java.util.TreeMap.firstKey(TreeMap.java:290)
	at java.util.TreeSet.first(TreeSet.java:394)
	at com.atlassian.jira.web.action.issue.util.ScreenTabErrorHelper.initialiseTabsWithErrors(ScreenTabErrorHelper.java:60)
	at com.atlassian.jira.web.action.issue.CommentAssignIssue.initTabsWithErrors(CommentAssignIssue.java:125)
	... 430 more

/**
 * Populates the set of field screen tabs with the tabs which contain errors. This is based on the error collection
 * supplied, which is a mapping from field names to error messages. Will return the index of the tab to be selected,
 * which is either the first tab with an error, or simply the first tab.
 *
 * @param tabsWithErrors      the set of tabs to populate
 * @param errors              the error collection
 * @param fieldScreenRenderer the field screen renderer to resolve {@link FieldScreenRenderTab} from field ids.
 * @param webParameters       the Webwork parameters
 * @return the (1-based) index of the tab to be selected.
 */
public int initialiseTabsWithErrors(final SortedSet<FieldScreenRenderTab> tabsWithErrors, final Map<String, ?> errors, final FieldScreenRenderer fieldScreenRenderer, final Map webParameters) {
    if (errors != null && !errors.isEmpty()) {
        // Record the tabs which have fields with errors on them
        for (String fieldId : errors.keySet()) {
            // some code here
        }

        // Add 1 as the status' counts in WW iterators start at 1 (not 0)
        return tabsWithErrors.first().getPosition() + 1; //line 60
    } else {
        return 1;
    }
}