Error in compiling project with Vaadin Add-on after migration to V6.5

I am trying to Vaadin Addon GanttChart in V 6.5 but having the following exception. It works well in previous version though.


:app-web-toolkit:buildWidgetSet
GWT Compiler args: 
[-war, D:\Studio Projects\demo\gantt-demo\ganttvaadin2\modules\web-toolkit\build\gwt\widgetset, -strict, -style, OBF, -logLevel, INFO, -localWorkers, 3, -optimize, 9, com.company.ganttvaadin2.web.toolkit.ui.AppWidgetSet]
JVM Args:
[-Djava.awt.headless=true, -Xmx768m, -Xss8m]
May 01, 2017 8:25:36 PM java.util.prefs.WindowsPreferences <init>
WARNING: Could not open/create prefs root node Software\JavaSoft\Prefs at root 0x80000002. Windows RegCreateKeyEx(...) returned error code 5.
Compiling module com.company.ganttvaadin2.web.toolkit.ui.AppWidgetSet
   Tracing compile failure path for type 'java.util.InternalJsStringMap'
      [ERROR] Errors in 'com/google/gwt/emul/java/util/InternalJsStringMap.java'
         [ERROR] Line 154: The method elementAdded() is undefined for the type AbstractHashMap<K,V>
         [ERROR] Line 166: The method elementRemoved() is undefined for the type AbstractHashMap<K,V>
   Tracing compile failure path for type 'java.util.InternalJsHashCodeMap'
      [ERROR] Errors in 'com/google/gwt/emul/java/util/InternalJsHashCodeMap.java'
         [ERROR] Line 120: The method elementAdded() is undefined for the type AbstractHashMap<K,V>
         [ERROR] Line 137: The method elementRemoved() is undefined for the type AbstractHashMap<K,V>
   [ERROR] Aborting compile due to errors in some input files
:app-web-toolkit:buildWidgetSet FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app-web-toolkit:buildWidgetSet'.
> Process 'command 'C:\Program Files\Java\jdk1.8.0_112\bin\java.exe'' finished with non-zero exit value 1

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

BUILD FAILED

Is it because of my Java, WIndows or anything else? Thanks for any help

Hi,

This add-on brings old transitive dependency on vaadin-client and gwt-user that are incompatible with cuba ones. If you want to use this add-on then change dependency definition in your build.gradle manually to:


compile('org.tltv.gantt:gantt-addon:0.9.5') {
    exclude(group: 'com.vaadin', module: 'vaadin-client')
}

Here we exclude vaadin-client. After that you can build your project without errors.

1 Like

Hi
I did that and here is the result. It seems that there is still a compatibility issue e.g. elementAdded(), elementRemoved() …


GWT Compiler args: 
[-war, D:\Studio Projects\demo\gantt-demo\gantt-demo\modules\web-toolkit\build\gwt\widgetset, -strict, -style, OBF, -logLevel, INFO, -localWorkers, 3, -optimize, 9, com.company.ganttdemo.web.toolkit.ui.AppWidgetSet]
JVM Args:
[-Djava.awt.headless=true, -Xmx768m, -Xss8m]
May 05, 2017 1:23:52 PM java.util.prefs.WindowsPreferences <init>
WARNING: Could not open/create prefs root node Software\JavaSoft\Prefs at root 0x80000002. Windows RegCreateKeyEx(...) returned error code 5.
Compiling module com.company.ganttdemo.web.toolkit.ui.AppWidgetSet
   Tracing compile failure path for type 'java.util.InternalJsHashCodeMap'
      [ERROR] Errors in 'jar:file:/C:/Users/Mortoza/.gradle/caches/modules-2/files-2.1/com.vaadin.external.gwt/gwt-user/2.7.0.vaadin4/926666000e33edcc06604a6a19c65e9cfe7ca6df/gwt-user-2.7.0.vaadin4.jar!/com/google/gwt/emul/java/util/InternalJsHashCodeMap.java'
         [ERROR] Line 120: The method elementAdded() is undefined for the type AbstractHashMap<K,V>
         [ERROR] Line 137: The method elementRemoved() is undefined for the type AbstractHashMap<K,V>
   Tracing compile failure path for type 'java.util.InternalJsStringMap'
      [ERROR] Errors in 'jar:file:/C:/Users/Mortoza/.gradle/caches/modules-2/files-2.1/com.vaadin.external.gwt/gwt-user/2.7.0.vaadin4/926666000e33edcc06604a6a19c65e9cfe7ca6df/gwt-user-2.7.0.vaadin4.jar!/com/google/gwt/emul/java/util/InternalJsStringMap.java'
         [ERROR] Line 154: The method elementAdded() is undefined for the type AbstractHashMap<K,V>
         [ERROR] Line 166: The method elementRemoved() is undefined for the type AbstractHashMap<K,V>
   [ERROR] Aborting compile due to errors in some input files
:app-web-toolkit:buildWidgetSet FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app-web-toolkit:buildWidgetSet'.
> Process 'command 'C:\Program Files\Java\jdk1.8.0_112\bin\java.exe'' finished with non-zero exit value 1

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

BUILD FAILED

Total time: 2 mins 25.82 secs
[13:25:12.399] Task 'deploy, start' failed
org.gradle.process.internal.ExecException: Process 'command 'C:\Program Files\Java\jdk1.8.0_112\bin\java.exe'' finished with non-zero exit value 1

Here is my grade file



buildscript {
    ext.cubaVersion = '6.5.0'
    repositories {
        maven {
            url 'https://repo.cuba-platform.com/content/groups/work'
            credentials {
                username(rootProject.hasProperty('repoUser') ? rootProject['repoUser'] : 'cuba')
                password(rootProject.hasProperty('repoPass') ? rootProject['repoPass'] : 'cuba123')
            }
        }
        
    }
    dependencies {
        classpath "com.haulmont.gradle:cuba-plugin:$cubaVersion"
    }
}

def globalModule = project(':app-global')
def webThemesModule= project(':app-web-themes')
def coreModule = project(':app-core')
def guiModule = project(':app-gui')
def webModule = project(':app-web')
def webToolkitModule = project(':app-web-toolkit')

def servletApi = 'org.apache.tomcat:tomcat-servlet-api:8.0.26'


apply(plugin: 'idea')
apply(plugin: 'cuba')

cuba {
    artifact {
        group = 'com.company.ganttdemo'
        version = '0.1'
        isSnapshot = true
    }
    tomcat {
        dir = "$project.rootDir/build/tomcat"
    }
    ide {
        copyright = '''Copyright (c) ${today.year} ${project.name}''' // Copyright Notice for IDEA project
        classComment ='''/**
 * @author ${USER}
 */'''
        
    }
}

dependencies {
    appComponent("com.haulmont.cuba:cuba-global:$cubaVersion")
}


def hsql = 'org.hsqldb:hsqldb:2.2.9'

configure([globalModule, coreModule, guiModule, webModule, webToolkitModule]) {
    apply(plugin: 'java')
    apply(plugin: 'maven')
    apply(plugin: 'idea')
    apply(plugin: 'cuba')

    dependencies {
        testCompile('junit:junit:4.12')
    }

    task sourceJar(type: Jar) {
        from file('src')
        classifier = 'sources'
    }

    artifacts {
        archives sourceJar
    }
}

configure(globalModule) {
    dependencies {

    }

    task enhance(type: CubaEnhancing)
    
}
configure(webThemesModule) {
    apply(plugin: 'java')
    apply(plugin: 'maven')
    apply(plugin: 'cuba')

    appModuleType = 'web-themes'

    buildDir = file('../build/scss-themes')

    sourceSets {
        main {
            java {
                srcDir '.'
            }
            resources {
                srcDir '.'
            }
        }
    }
}


configure(coreModule) {

    configurations {
        jdbc
        dbscripts
    }

    dependencies {
        compile(globalModule)
        provided(servletApi)
        jdbc(hsql)
        testRuntime(hsql)

    }

    task cleanConf(description: 'Cleans up conf directory') << {
        def dir = new File(cuba.tomcat.dir, '/conf/app-core')
        if (dir.isDirectory()) {
            ant.delete(includeemptydirs: true) {
                fileset(dir: dir, includes: '**/*', excludes: 'local.app.properties')
            }
        }
    }

    task deploy(dependsOn: [assemble, cleanConf], type: CubaDeployment) {
        appName = 'app-core'
        appJars('app-global', 'app-core')
    }

    task createDb(dependsOn: assembleDbScripts, description: 'Creates local database', type: CubaDbCreation) {
        dbms = 'hsql'
        dbmsVersion = 'null'
        host = 'localhost'
        dbName = 'demo'
        dbUser = 'sa'
        dbPassword = ''
    }

    task updateDb(dependsOn: assembleDbScripts, description: 'Updates local database', type: CubaDbUpdate) {
        dbms = 'hsql'
        dbmsVersion = 'null'
        host = 'localhost'
        dbName = 'demo'
        dbUser = 'sa'
        dbPassword = ''
    }
}

configure(guiModule) {
    dependencies {
        compile(globalModule)

    }

    task deployConf(type: Copy) {
        from file('src')
        include "com/company/ganttdemo/**"
        into "$cuba.tomcat.dir/conf/app"
    }
}

configure(webModule) {
    configurations {
        webcontent
        themes
        
    }

    dependencies {
        provided(servletApi)
        compile(guiModule)
        compile('org.tltv.gantt:gantt-addon:0.9.5') {
            exclude(group: 'com.vaadin', module: 'vaadin-client')
        }
        themes('org.tltv.gantt:gantt-addon:0.9.5') {
            exclude(group: 'com.vaadin')
        }
        themes("com.haulmont.cuba:cuba-web-themes:$cubaVersion")
        provided("com.haulmont.cuba:cuba-web-themes:$cubaVersion")
        compile('org.tltv.gantt:gantt-addon:0.9.5')
    }

    jar {
        with copySpec {
            from sourceSets.main.allJava
            include "com/company/ganttdemo/web/toolkit/ui/client/**"
        }
    }


    task webArchive(type: Zip) {
        from file('web')
        classifier = 'web'
    }

    artifacts {
        archives webArchive
    }

    task deployConf(type: Copy) {
        from file('src')
        include "com/company/ganttdemo/**"
        into "$cuba.tomcat.dir/conf/app"
    }

    task clearMessagesCache(type: CubaClearMessagesCache) {
        appName = 'app'
    }
    deployConf.dependsOn clearMessagesCache

    task cleanConf(description: 'Cleans up conf directory') << {
        def dir = new File(cuba.tomcat.dir, '/conf/app')
        if (dir.isDirectory()) {
            ant.delete(includeemptydirs: true) {
                fileset(dir: dir, includes: '**/*', excludes: 'local.app.properties')
            }
        }
    }

    task deploy(dependsOn: [assemble, cleanConf], type: CubaDeployment) {
        appName = 'app'
        appJars('app-global', 'app-gui', 'app-web')
    }
    task buildScssThemes(type: CubaWebScssThemeCreation)
    task deployThemes(type: CubaDeployThemeTask, dependsOn: buildScssThemes)
    assemble.dependsOn buildScssThemes
}

configure(webToolkitModule) {
    dependencies {
        compile(webModule)
        runtime(servletApi)

    }

    jar {
        from sourceSets.main.allJava
    }


    task buildWidgetSet(type: CubaWidgetSetBuilding) {
        widgetSetClass = 'com.company.ganttdemo.web.toolkit.ui.AppWidgetSet'
    }
    
    task debugWidgetSet(type: CubaWidgetSetDebug) {
        widgetSetClass = 'com.company.ganttdemo.web.toolkit.ui.AppWidgetSet'
    } 

    task webArchive(dependsOn: buildWidgetSet, type: Zip) {
        from file("$buildDir/web")
        classifier = 'web'
    }

    artifacts {
        archives webArchive
    }

    task deploy(dependsOn: buildWidgetSet) << {
        delete {
            "$cuba.tomcat.dir/webapps/app/VAADIN/widgetsets"
        }
        copy {
            from "$buildDir/web"
            into "$cuba.tomcat.dir/webapps/app"
            exclude '**/gwt-unitCache/'
        }
    }
}




task undeploy(type: Delete, dependsOn: ':app-web:cleanConf') {
    delete("$cuba.tomcat.dir/shared")
    delete("$cuba.tomcat.dir/webapps/app-core")
    delete("$cuba.tomcat.dir/webapps/app")
}

task restart(dependsOn: ['stop', ':app-core:deploy', ':app-web:deploy'], description: 'Redeploys applications and restarts local Tomcat') << {
    ant.waitfor(maxwait: 6, maxwaitunit: 'second', checkevery: 2, checkeveryunit: 'second') {
        not {
            socket(server: 'localhost', port: '8787')
        }
    }
    start.execute()
}

task wrapper(type: Wrapper) {
    gradleVersion = '3.1'
}

apply from: 'extra.gradle'

Please check your script, you have added compile(‘org.tltv.gantt:gantt-addon:0.9.5’) dependency twice. There you should use only one declaration of this dependency with exclude of vaadin-client library.

After removing the duplicate line, now getting another surprise! Looks like something wrong with anonymous session. It complies well but when i run it, get exception without log in prompt.


4:53:57.249 ERROR c.h.c.security.app.LoginWorkerBean - Unable to login anonymous session
com.haulmont.cuba.security.global.LoginException: Unknown login name or bad password: anonymous
        at com.haulmont.cuba.security.app.LoginWorkerBean.loginAnonymous(LoginWorkerBean.java:215) [cuba-core-6.5.0.jar:6.5.0]
        at com.haulmont.cuba.security.app.LoginWorkerBean.initializeAnonymousSession(LoginWorkerBean.java:505) [cuba-core-6.5.0.jar:6.5.0]
        at com.haulmont.cuba.security.app.LoginWorkerBean.getSession(LoginWorkerBean.java:420) [cuba-core-6.5.0.jar:6.5.0]
        at com.haulmont.cuba.security.app.LoginServiceBean.getSession(LoginServiceBean.java:165) [cuba-core-6.5.0.jar:6.5.0]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_112]
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_112]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_112]
        at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_112]
        at com.haulmont.cuba.core.sys.remoting.LocalServiceInvokerImpl.invoke(LocalServiceInvokerImpl.java:94) [cuba-core-6.5.0.jar:6.5.0]
        at com.haulmont.cuba.web.sys.remoting.LocalServiceProxy$LocalServiceInvocationHandler.invoke(LocalServiceProxy.java:148) [cuba-web-6.5.0.jar:6.5.0]
        at com.sun.proxy.$Proxy20.getSession(Unknown Source) [na:na]
        at com.haulmont.cuba.web.DefaultConnection.doLoginAnonymous(DefaultConnection.java:101) [cuba-web-6.5.0.jar:6.5.0]
        at com.haulmont.cuba.web.DefaultConnection.loginAnonymous(DefaultConnection.java:67) [cuba-web-6.5.0.jar:6.5.0]
        at com.haulmont.cuba.web.AppUI.setupUI(AppUI.java:262) [cuba-web-6.5.0.jar:6.5.0]
        at com.haulmont.cuba.web.AppUI.init(AppUI.java:203) [cuba-web-6.5.0.jar:6.5.0]
        at com.vaadin.ui.UI.doInit(UI.java:693) [vaadin-server-7.7.8.cuba.4.jar:7.7.8.cuba.4]
        at com.vaadin.server.communication.UIInitHandler.getBrowserDetailsUI(UIInitHandler.java:216) [vaadin-server-7.7.8.cuba.4.jar:7.7.8.cuba.4]
        at com.vaadin.server.communication.UIInitHandler.synchronizedHandleRequest(UIInitHandler.java:74) [vaadin-server-7.7.8.cuba.4.jar:7.7.8.cuba.4]
        at com.vaadin.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:41) [vaadin-server-7.7.8.cuba.4.jar:7.7.8.cuba.4]
        at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1422) [vaadin-server-7.7.8.cuba.4.jar:7.7.8.cuba.4]
        at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:385) [vaadin-server-7.7.8.cuba.4.jar:7.7.8.cuba.4]
        at com.haulmont.cuba.web.sys.CubaApplicationServlet.serviceAppRequest(CubaApplicationServlet.java:278) [cuba-web-6.5.0.jar:6.5.0]
        at com.haulmont.cuba.web.sys.CubaApplicationServlet.service(CubaApplicationServlet.java:187) [cuba-web-6.5.0.jar:6.5.0]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) [servlet-api.jar:na]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291) [catalina.jar:8.0.26]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:8.0.26]
        at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) [tomcat-websocket.jar:8.0.26]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) [catalina.jar:8.0.26]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:8.0.26]
        at com.haulmont.cuba.web.sys.CubaHttpFilter.handleNotFiltered(CubaHttpFilter.java:108) [cuba-web-6.5.0.jar:6.5.0]
        at com.haulmont.cuba.web.sys.CubaHttpFilter.doFilter(CubaHttpFilter.java:95) [cuba-web-6.5.0.jar:6.5.0]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) [catalina.jar:8.0.26]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:8.0.26]
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219) [catalina.jar:8.0.26]
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106) [catalina.jar:8.0.26]
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502) [catalina.jar:8.0.26]
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142) [catalina.jar:8.0.26]
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) [catalina.jar:8.0.26]
        at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616) [catalina.jar:8.0.26]
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88) [catalina.jar:8.0.26]
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518) [catalina.jar:8.0.26]
        at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091) [tomcat-coyote.jar:8.0.26]
        at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673) [tomcat-coyote.jar:8.0.26]
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1526) [tomcat-coyote.jar:8.0.26]
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1482) [tomcat-coyote.jar:8.0.26]
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_112]
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_112]
        at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-util.jar:8.0.26]
        at java.lang.Thread.run(Thread.java:745) [na:1.8.0_112]
14:53:57.262 ERROR com.haulmont.cuba.web.AppUI - Unable to init ui
com.haulmont.cuba.security.global.LoginFailedException: Unable to obtain anonymous session with id 6a15c70b-15fc-251e-2645-0c5877bfe1f4
        at com.haulmont.cuba.web.DefaultConnection.loginAnonymous(DefaultConnection.java:69) ~[cuba-web-6.5.0.jar:6.5.0]
        at com.haulmont.cuba.web.AppUI.setupUI(AppUI.java:262) ~[cuba-web-6.5.0.jar:6.5.0]
        at com.haulmont.cuba.web.AppUI.init(AppUI.java:203) ~[cuba-web-6.5.0.jar:6.5.0]
        at com.vaadin.ui.UI.doInit(UI.java:693) [vaadin-server-7.7.8.cuba.4.jar:7.7.8.cuba.4]
        at com.vaadin.server.communication.UIInitHandler.getBrowserDetailsUI(UIInitHandler.java:216) [vaadin-server-7.7.8.cuba.4.jar:7.7.8.cuba.4]
        at com.vaadin.server.communication.UIInitHandler.synchronizedHandleRequest(UIInitHandler.java:74) [vaadin-server-7.7.8.cuba.4.jar:7.7.8.cuba.4]
        at com.vaadin.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:41) [vaadin-server-7.7.8.cuba.4.jar:7.7.8.cuba.4]
        at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1422) [vaadin-server-7.7.8.cuba.4.jar:7.7.8.cuba.4]
        at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:385) [vaadin-server-7.7.8.cuba.4.jar:7.7.8.cuba.4]
        at com.haulmont.cuba.web.sys.CubaApplicationServlet.serviceAppRequest(CubaApplicationServlet.java:278) [cuba-web-6.5.0.jar:6.5.0]
        at com.haulmont.cuba.web.sys.CubaApplicationServlet.service(CubaApplicationServlet.java:187) [cuba-web-6.5.0.jar:6.5.0]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) [servlet-api.jar:na]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291) [catalina.jar:8.0.26]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:8.0.26]
        at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) [tomcat-websocket.jar:8.0.26]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) [catalina.jar:8.0.26]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:8.0.26]
        at com.haulmont.cuba.web.sys.CubaHttpFilter.handleNotFiltered(CubaHttpFilter.java:108) [cuba-web-6.5.0.jar:6.5.0]
        at com.haulmont.cuba.web.sys.CubaHttpFilter.doFilter(CubaHttpFilter.java:95) [cuba-web-6.5.0.jar:6.5.0]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) [catalina.jar:8.0.26]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) [catalina.jar:8.0.26]
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219) [catalina.jar:8.0.26]
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106) [catalina.jar:8.0.26]
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502) [catalina.jar:8.0.26]
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142) [catalina.jar:8.0.26]
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) [catalina.jar:8.0.26]
        at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616) [catalina.jar:8.0.26]
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88) [catalina.jar:8.0.26]
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518) [catalina.jar:8.0.26]
        at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091) [tomcat-coyote.jar:8.0.26]
        at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673) [tomcat-coyote.jar:8.0.26]
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1526) [tomcat-coyote.jar:8.0.26]
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1482) [tomcat-coyote.jar:8.0.26]
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_112]
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_112]
        at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-util.jar:8.0.26]
        at java.lang.Thread.run(Thread.java:745) [na:1.8.0_112]

Please open a separate topic and describe your problem in details there.

I’ve checked this add-on and found an error in /org/tltv/gantt/client/StepConnector.java:175 You have to set description for each org.tltv.gantt.client.shared.Step to get rid of that NPE on browser side.