We Keep Coding

How to change logger level in log4j2.xml at runtime without restarting tomcat service

I was using log4j 1.2 earlier and I recently migrated to log4j 2.0
I was using below listener class in log4j 1.2 in web.xml
<listener>
<listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
</listener>
This listener class is removed after log4j 2.0 and I want replacement of this listener class which allow me to change logger level at runtime and update without restarting tomcat service in my web application.
I have tried below listener but this is also restarting tomcat while changing configuration in log4j2.xml
<listener>
<listener-class>org.apache.logging.log4j.core.web.Log4jContextListener</listener-class>
</listener>
I am seeing below Exceptions and warnings while changing log4j2.xml and then it restarts tomcat:
WARNING: The web application [demo] appears to have started a thread named [pool-UCCAdminMonitor-1] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread:
sun.misc.Unsafe.park(Native Method)
java.util.concurrent.locks.LockSupport.parkNanos(Unknown Source)
java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(Unknown Source)
java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(Unknown Source)
java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(Unknown Source)
java.util.concurrent.ThreadPoolExecutor.getTask(Unknown Source)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
java.lang.Thread.run(Unknown Source)
Jul 14, 2020 8:36:25 AM org.apache.catalina.loader.WebappClassLoaderBase clearReferencesThreads
Exception in thread "Log4j2-TF-10-ConfiguratonFileWatcher-19" java.lang.IllegalStateException: Illegal access: this web application instance has been stopped already. Could not load [META-INF/services/javax.xml.parsers.DocumentBuilderFactory]. The following stack trace is thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access.
at org.apache.catalina.loader.WebappClassLoaderBase.checkStateForResourceLoading(WebappClassLoaderBase.java:1385)
at org.apache.catalina.loader.WebappClassLoaderBase.findResources(WebappClassLoaderBase.java:985)
at org.apache.catalina.loader.WebappClassLoaderBase.getResources(WebappClassLoaderBase.java:1086)
at java.util.ServiceLoader$LazyIterator.hasNextService(Unknown Source)
at java.util.ServiceLoader$LazyIterator.hasNext(Unknown Source)
at java.util.ServiceLoader$1.hasNext(Unknown Source)
at javax.xml.parsers.FactoryFinder$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at javax.xml.parsers.FactoryFinder.findServiceProvider(Unknown Source)
at javax.xml.parsers.FactoryFinder.find(Unknown Source)
at javax.xml.parsers.DocumentBuilderFactory.newInstance(Unknown Source)
at org.apache.logging.log4j.core.config.xml.XmlConfiguration.newDocumentBuilder(XmlConfiguration.java:183)
at org.apache.logging.log4j.core.config.xml.XmlConfiguration.<init>(XmlConfiguration.java:89)
at org.apache.logging.log4j.core.config.xml.XmlConfiguration.reconfigure(XmlConfiguration.java:272)
at org.apache.logging.log4j.core.LoggerContext.onChange(LoggerContext.java:752)
at org.apache.logging.log4j.core.util.AbstractWatcher$ReconfigurationRunnable.run(AbstractWatcher.java:92)
at java.lang.Thread.run(Unknown Source)
INFO: Illegal access: this web application instance has been stopped already. Could not load [org.apache.logging.log4j.core.lookup.JndiLookup]. The following stack trace is thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access.
java.lang.IllegalStateException: Illegal access: this web application instance has been stopped already. Could not load [org.apache.logging.log4j.core.lookup.JndiLookup]. The following stack trace is thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access.
at org.apache.catalina.loader.WebappClassLoaderBase.checkStateForResourceLoading(WebappClassLoaderBase.java:1385)
at org.apache.catalina.loader.WebappClassLoaderBase.checkStateForClassLoading(WebappClassLoaderBase.java:1373)
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1226)
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1188)
at org.apache.logging.log4j.util.LoaderUtil.loadClass(LoaderUtil.java:167)
at org.apache.logging.log4j.util.LoaderUtil.newInstanceOf(LoaderUtil.java:209)
at org.apache.logging.log4j.util.LoaderUtil.newCheckedInstanceOf(LoaderUtil.java:230)
at org.apache.logging.log4j.core.util.Loader.newCheckedInstanceOf(Loader.java:311)
at org.apache.logging.log4j.core.lookup.Interpolator.<init>(Interpolator.java:112)
at org.apache.logging.log4j.core.config.AbstractConfiguration.<init>(AbstractConfiguration.java:129)
at org.apache.logging.log4j.core.config.xml.XmlConfiguration.<init>(XmlConfiguration.java:76)
at org.apache.logging.log4j.core.config.xml.XmlConfiguration.reconfigure(XmlConfiguration.java:272)
at org.apache.logging.log4j.core.LoggerContext.onChange(LoggerContext.java:752)
at org.apache.logging.log4j.core.util.AbstractWatcher$ReconfigurationRunnable.run(AbstractWatcher.java:92)

Log4j 2 doesn't require that you provide your own listener. Instead, just add monitorInterval=nn the the Configuration element of you log4j2.xml where nn is the number of seconds to check the configuration. Log4j will then poll the file at that interval and reload the configuration if it changes.

Answering my own question -
First need to add below filter and listener in web.xml :
<listener>
<listener-class>org.apache.logging.log4j.web.Log4jServletContextListener</listener-class>
</listener>
<filter>
<filter-name>log4jServletFilter</filter-name>
<filter-class>org.apache.logging.log4j.web.Log4jServletFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>log4jServletFilter</filter-name>
<url-pattern>/*</url-pattern>
<dispatcher>REQUEST</dispatcher>
<dispatcher>FORWARD</dispatcher>
<dispatcher>INCLUDE</dispatcher>
<dispatcher>ERROR</dispatcher>
<dispatcher>ASYNC</dispatcher><!-- Servlet 3.0 w/ disabled auto-initialization only; not supported in 2.5 -->
</filter-mapping>
path of log4j2.xml should be /WEB-INF/log4j2.xml
After this while we change logger level it will not restart the tomcat service.

NoClassDefFoundError: org/apache/log4j/Logger in Java applet

At the moment, I'm developing java applet for e-signing documents with smartcard, current applet code on server side looks like
echo "<Applet Code=\"Main.class\"
name = \"eParakstitajs\"
mayscript=\"true\"
codebase = \"".SERVER_FULL_URL."/EDOC2.4.0._22.05\"
archive = \"
classesEDOC2.4.jar,
log4j-1.2.17.jar,
eparaksts-bc-1.43.0.jar,
eparaksts-client-2.4.0.jar,
eparaksts-lib-2.4.0.jar,
org.apache.commons.codec_1.3.0.v201101211617.jar,
pkcs11wrapper-1.2.18.jar,
plugin.jar,
signing-applet-2.4.0.jar,
slf4j-api-1.7.7.jar,
slf4j-log4j12-1.7.7.jar,
xmlsec-2.0.2.jar,
./config/\"
width=1
Height=1
>
<PARAM NAME=\"key\" VALUE=\"{$signKey}\">
<PARAM NAME=\"URL\" VALUE=\"".SERVER_FULL_URL."\">
<PARAM NAME=\"PIN1\" VALUE=\"{$_SESSION["userdata"]["PIN1"]}\">
<PARAM NAME=\"PIN2\" VALUE=\"{$_SESSION["userdata"]["PIN2"]}\">
<PARAM NAME=\"USERID\" VALUE=\"{$user[0]["id_lietotajs"]}\">
</Applet>";
On this stage everything is ok, and all listed libraries are in mentioned folder. (ClassesEDOC2.4.jar is my archive with classes, all other are third-party jars)
In my java code, I am instantiating object, based on class QualifiedSignatureHelper from jar eparaksts-lib-2.4.0.jar. And during execution, an exception appears
java.lang.NoClassDefFoundError: org/apache/log4j/Logger
at lv.eparaksts.helpers.QualifiedSignatureHelper.<clinit>(QualifiedSignatureHelper.java:26)
at CreateNewSignTimestampedAction.CreateNewSignTimestamped(CreateNewSignTimestampedAction.java:128)
at Main.init(Main.java:221)
at com.sun.deploy.uitoolkit.impl.awt.AWTAppletAdapter.init(Unknown Source)
at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.ClassNotFoundException: org.apache.log4j.Logger
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
... 6 more
I have decompiled class QualifiedSignatureHelper, and discovered that it imports log4j class, and also instantiating log4j object for some reasons
According to exception, QualifiedSignatureHelper class cant find log4j class. Any advice?

Solr 4.1 Core Initialization Failure [duplicate]

This question already has answers here:
Solr RequestHandler init failure
(2 answers)
Closed 7 years ago.
I have updated my version of Solr from 3.5 to 4.1
I have removed the old war file from my apache tomcat (7) webapps, and deployed the new war file that has been provided in the apache-solr package.
I got the following error upon trying to access solr from the web browser!
I have one core only(dbTrial)
Solr opens but this error appears.
SolrCore Initialization Failures
dbTrial: org.apache.solr.common.SolrException:org.apache.solr.common.SolrException: RequestHandler init failure
There are no SolrCores running.
Using the Solr Admin UI currently requires at least one SolrCore.
Unable to load environment info from null/admin/system?wt=json.
This interface requires that you activate the admin request handlers in all SolrCores by adding the following configuration to your solrconfig.xml:
Can you help me out? I have tried adding the request handler as specified, but it didn't work.
It seems that the new versions of solr need a new format for solrconfig file. can you assist please! thank you!
the log is the following:
????? ?????? 21, 2014 9:19:05 ? org.apache.solr.common.SolrException log
SEVERE: null:org.apache.solr.common.SolrException: RequestHandler init failure
at org.apache.solr.core.RequestHandlers.initHandlersFromConfig(RequestHandlers.java:168)
at org.apache.solr.core.SolrCore.<init>(SolrCore.java:657)
at org.apache.solr.core.SolrCore.<init>(SolrCore.java:566)
at org.apache.solr.core.CoreContainer.create(CoreContainer.java:850)
at org.apache.solr.core.CoreContainer.load(CoreContainer.java:534)
at org.apache.solr.core.CoreContainer.load(CoreContainer.java:356)
at org.apache.solr.core.CoreContainer$Initializer.initialize(CoreContainer.java:308)
at org.apache.solr.servlet.SolrDispatchFilter.init(SolrDispatchFilter.java:107)
at org.apache.catalina.core.ApplicationFilterConfig.initFilter(ApplicationFilterConfig.java:277)
at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:258)
at org.apache.catalina.core.ApplicationFilterConfig.setFilterDef(ApplicationFilterConfig.java:382)
at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:103)
at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4624)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5281)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:866)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:842)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:615)
at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:958)
at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1599)
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: org.apache.solr.common.SolrException: Error loading class 'solr.DisMaxRequestHandler'
at org.apache.solr.core.SolrResourceLoader.findClass(SolrResourceLoader.java:436)
at org.apache.solr.core.SolrCore.createInstance(SolrCore.java:469)
at org.apache.solr.core.SolrCore.createRequestHandler(SolrCore.java:540)
at org.apache.solr.core.RequestHandlers.initHandlersFromConfig(RequestHandlers.java:154)
... 25 more
Caused by: java.lang.ClassNotFoundException: solr.DisMaxRequestHandler
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.net.FactoryURLClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.apache.solr.core.SolrResourceLoader.findClass(SolrResourceLoader.java:420)
... 28 more

Check the Solr log for a better error of what the issue is when Solr is starting up - you'll probably have a better error message there than the one you can see in the Admin interface (which is the error triggered when the interface attempts to access the Solr core). The reason why the core or requestHandler isn't loading will be in the log file, and not in the message produced by the UI. Remember that logging also changed at 4.3, if you've updated to 4.10 (I see that you wrote 4.1, but if you're planning on going the whole way (or meant 4.10) - the logging might have to be configured as well).
You'll also want to consider the "going from 3 to 4" document, that details the changed to the configuration files (as solrconfig.xml changed a bit).
Update
The log shows that it's complaining about loading "solr.DisMaxRequestHandler". This has been deprecated for quite some time and has been removed - just use the standard request handler from the example solrconfig.xml instead.
<requestHandler name="standard" class="solr.SearchHandler" default="true">
<lst name="defaults">
<str name="echoParams">explicit</str>
</lst>
</requestHandler>

index.jsp not found (cannot be loaded)

i am trying to create a dynamic web app in Eclipse (Tomcat v7). The problem is that when i run my webapp index.jsp cannot be accessed. I can Access every other .jsp, but the index.jsp not.The next problem of course is ´that index.jsp cannot be loaded at the start of the app. I get the following message:
javax.servlet.ServletException: java.lang.NoClassDefFoundError: org/apache/jsp/index_jsp (wrong name: org/apache/jsp/Index_jsp)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:343)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
root cause
java.lang.NoClassDefFoundError: org/apache/jsp/index_jsp (wrong name: org/apache/jsp/Index_jsp)
java.lang.ClassLoader.defineClass1(Native Method)
java.lang.ClassLoader.defineClass(Unknown Source)
java.security.SecureClassLoader.defineClass(Unknown Source)
java.net.URLClassLoader.defineClass(Unknown Source)
java.net.URLClassLoader.access$100(Unknown Source)
java.net.URLClassLoader$1.run(Unknown Source)
java.net.URLClassLoader$1.run(Unknown Source)
java.security.AccessController.doPrivileged(Native Method)
java.net.URLClassLoader.findClass(Unknown Source)
org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:132)
org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:63)
org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:172)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:369)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
I have tried everything (the last option was to create a index.html and redirect it to the index.jsp but it didn't work). I have also tried to copy index.jsp in every folder of the app but it also didn't work.
Here is my web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<display-name>Test_WebApp_1</display-name>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
I have also searched on Google, and there where some cases where the index.jsp was not loading, but the solutions didn't help me.
Does anybode has some idea ? Could this be something with Apache ? I have tried to run Version 6.0 but i could not start it because it didn't support some of the modules used in my app.
So, i am happy for any Information
Kinde regards
Semir

i have tried something else. I have exported my app as a war and deployed it on Apache. When i run my app right from Apache it works fine, and the index.jsp is being loaded. So i assume it is something in eclipse
edit : i solved it by installing the jdk develpment kit and Setting the JAVA_HOME Variable
thanks für the answers

Do you work under a sensitive case OS?
Because your error is: org/apache/jsp/index_jsp (wrong name: org/apache/jsp/Index_jsp
with an uppercase on Index_jsp.
Check your UR, check your file name...

Java Web Start can't find jar with formatted version filename

I have simple-as-can-be Web Start application sitting on a file server. The directory consists of the following:
foo__V1.1.jar
runfoo.jnlp
The contents of runfoo.jnlp is as follows:
<?xml version="1.0" encoding="utf-8"?>
<jnlp spec="1.0+" href="http://myserver.com/runfoo.jnlp" codebase="http://myserver.com">
<information>
<title>Foo</title>
</information>
<security>
<all-permissions/>
</security>
<resources>
<j2se version="1.7.0_06+" href="http://java.sun.com/products/autodl/j2se" />
<jar href="foo.jar" main="true" version="1.0+"/>
<property name="jnlp.versionEnabled" value="true"/>
</resources>
<application-desc name="Foo" main-class="com.myserver.foo.Foo" width="640" height="480" />
<update check="always" policy="always" />
</jnlp>
The issue is that Web Start is attempting to access a file at http://myserver.com/runfoo.jnlp?version-id=1.0%2B, and not finding it.
I assume there's some extra step required to have Web Start automatically grab the latest jar version in this simple instance, but after a lot of Googling all I've found is the same steps over and over:
rename file to <file_name>__V<versionnumber>.jar
Add the versionEnabled property to the jnlp
enjoy versioned goodness
The jnlp file runs absolutely fine when I specify an explicit file name, but always fails when I've tried to implement versioning.
I'm sure I'm missing something vital but I haven't been able to find it anywhere. I'm guessing that although my set-up is simple, it's not simple-as-can-be-and-also-work.
Any help will be much appreciated :)
The explicit exception is:
com.sun.deploy.net.FailedDownloadException: Unable to load resource: (http://myserver.com/foo.jar?version-id=1.0%2B, 1.0+)
I've also tried removing the + from the version specification and the same error occurs (apart from a missing plus of course). Writting foo__V1.1.jar in the jnlp file works but of course defeats the whole point of this.

The versioned file names are a convention used by the JNLP download servlet to know what to serve when the client asks for lib.jar?version=something. You need the download servlet on the server side (or you need to duplicate its behaviour in mod_rewrite rules or similar), just the plain files with versions names is not enough.

For followers, a similar issue for me
java.io.IOException: Error returned: 10 Could not locate resource
at com.sun.deploy.net.DownloadEngine.actionDownload(Unknown Source)
at com.sun.deploy.net.DownloadEngine.downloadResource(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at com.sun.javaws.LaunchDownload$DownloadTask.call(Unknown Source)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
"unable to launch application"
com.sun.deploy.net.FailedDownloadException: Unable to load resource: (http://host:port/webapp_name/app/jar-name.jar?version-id=1.5.0-20160707.182810-19, 1.5.0-20160707.182810-19)
at com.sun.deploy.net.DownloadEngine.actionDownload(Unknown Source)
at com.sun.deploy.net.DownloadEngine.downloadResource(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at com.sun.javaws.LaunchDownload$DownloadTask.call(Unknown Source)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
meant "the special internal file version.xml didn't match up right with the filenames deployed and existent in the web-app directory":
ref: http://docs.oracle.com/javase/6/docs/technotes/guides/javaws/developersguide/downloadservletguide.html