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Selenium - Exception in thread "main" java.lang.NoClassDefFoundError: org/reactivestreams/Publisher

I am creating a Maven project for Selenium in eclipse. Don't know why it threw log4j error (It didn't used to earlier, before upgrading Eclipse). The error is as follows -
I have already added "log4j.properties" file under src/main/resources as -
log4j.rootLogger=INFO, stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
Also added dependency as following in POM.xml -
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.26</version>
</dependency>
Artifacts used -
Eclipse - Version: 2020-06 (4.16.0)
Maven artifact id - maven-archetype-quickstart - v1.4
Selenium version - 3.141.59

The error is not related to log4j. The error is for org.reactivestreams.Publisher. Add the following Maven dependency to get it:
<!-- https://mvnrepository.com/artifact/org.reactivestreams/reactive-streams -->
<dependency>
<groupId>org.reactivestreams</groupId>
<artifactId>reactive-streams</artifactId>
<version>1.0.3</version>
</dependency>
Make sure to update the project after adding the dependency.

spring boot .war tomcat application logs not there

I am trying to write to my webapp logs to a .log file in the /logs directory in tomcat but the file is not generated nor is any logging output going to the console other than the spring logs and tomcat logs. When I run spring boot as a jar file with the embedded tomcat it writes to the log file just fine, but as soon as I deploy to tomcat via the webapps folder the application logs are no where to be found.
SpringBoot 2.1.2
Java 1.8
Tomcat 8.5
I have tried:
configuring LOGGING_CONFIG in setenv.sh
Multiple loggers.. logback, java utils etc..
application.properties:
logging.file=../logs/my-app.log
logging.level.org.springframework=INFO
logging.level.com.bose=DEBUG
log4j.properties for log4j:
log4j.rootLogger=${marge.log.level}, stdout, file
# Direct log messages to a log file
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.File=marge.log
#when stdout is also specified it will not write to the file
log4j.appender.file.MaxFileSize=1MB
# Keep one backup file
log4j.appender.file.MaxBackupIndex=1
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d{dd MMM yyyy HH:mm:ss,SSS} [%c] [%-5p] %n%m%n
# Direct log messages to stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
# stdout uses PatternLayout
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{HH:mm:ss,SSS} [%c] [%-5p] %n%m%n
# Print only messages of level DEBUG or above in the package com.bose
log4j.logger.com.app=${log.level}
Expected: when I deploy my webapp in /webapps the application logs (generated by log4j) should be in my-app.log in the /logs directory
Actual: No file is generated and no logs are even in stdout/console

By default spring boot uses logback as a logging binder, so the key concept here to exclude logback first then include log4j
Example:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
<exclusions>
<exclusion>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-logging</artifactId>
</exclusion>
</exclusions>
</dependency>
After that add log4j 2 dependency:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-log4j2</artifactId>
</dependency>
Add your log4j2.properties file to src/main/resources to be on classpath
Finally pay attention to what logging interface you are using this is important, with the above configuration you should use apache logging like:
package com.example;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
import org.springframework.context.ApplicationContext;
#SpringBootApplication
public class Application extends SpringBootServletInitializer {
private static final Logger LOGGER = LogManager.getLogger(Application.class);
public static void main(String[] args){
ApplicationContext ctx = SpringApplication.run(Application.class, args);
LOGGER.info("Info level log message");
LOGGER.debug("Debug level log message");
LOGGER.error("Error level log message");
}
}

Can't disable quartz-scheduler logging using SLF4J

After adding quartz-scheduler to a project, Tomcat's server log is being spammed with the following message:
[INFO] [talledLocalContainer] 12:15:06.319
[DefaultQuartzScheduler_QuartzSchedulerThread] DEBUG
o.quartz.core.QuartzSchedulerThread - batch acquisition of 0 triggers
I'm trying to disable that log message, which repeats every 25-seconds or so. I've been through a number of other answers to this same question, such as:
Disable quartz logging
stop quartz debug logging log4j
Disabling Log4J Output in Java
...and none of the approaches suggested are working.
I have the following dependencies declared in pom.xml:
<dependency>
<groupId>org.quartz-scheduler</groupId>
<artifactId>quartz</artifactId>
<version>2.2.1</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.5</version>
</dependency>
And I've added the following log4j.properties settings to my project:
log4j.rootLogger=OFF
log4j.logger.quartz=OFF
log4j.logger.o.quartz=OFF
log4j.logger.org.quartz=OFF
...and also the following simplelogger.properties:
org.slf4j.simpleLogger.defaultLogLevel=error
In addition to attempting the programmatic solution suggested on one of the linked answers, which should disable all logging and goes roughly like:
List<Logger> loggers = Collections.<Logger>list(LogManager.getCurrentLoggers());
loggers.add(LogManager.getRootLogger());
for ( Logger logger : loggers ) {
logger.setLevel(Level.OFF);
}
That seems to disable everything except the log message from quartz when it runs.
Is there a way to get rid of the log message from quartz, short of modifying the quartz source-code to remove it?

The logging entry above doesn't look like Log4J. I think thats ACL or JUL. When you are using Slf4j to Log4J, you also need to redirect these frameworks to Slf4j. Add these dependencies to your project as well:
<!--Redirect Apache Commons Logging to Slf4J -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>jcl-over-slf4j</artifactId>
<version>1.7.5</version>
</dependency>
<!--Redirect Java Util Logging to Slf4J -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>jul-to-slf4j</artifactId>
<version>1.7.5</version>
</dependency>
Read this doc page about redirecting Jul to Slf4J, too. Be sure to exclude any existing commons-logging.jar files from your project, through Maven.
(From the Slf4J documentation page)
And if all else fails, try the following code:
//see if we can find the offending logger through slf4j's LoggerFactory
org.slf4j.Logger logger =
LoggerFactory.getLogger(Class.forName("org.quartz.core.QuartzSchedulerThread"));
if (logger != null && logger instanceof ch.qos.logback.classic.Logger) {
//the slf4j Logger interface doesn't expose any configuration API's, but
//we can cast to a class that does; so cast it and disable the logger
((ch.qos.logback.classic.Logger)logger).setLevel(
ch.qos.logback.classic.Level.OFF);
}

Send/redirect/route java.util.logging.Logger (JUL) to Logback using SLF4J?

Is it possible to have a typical call to java.util.logging.Logger and have it route to Logback using SLF4J? This would be nice since I wouldn't have to refactor the old jul code line by line.
EG, say we have this line:
private static Logger logger = Logger.getLogger(MahClass.class.getName());
//...
logger.info("blah blah blah");
It would be nice to configure this to call through SLF4J.

It's very easy and not a performance issue anymore.
There are two ways documented in the SLF4J manual. There are also precise examples in the Javadocs
Add jul-to-slf4j.jar to your classpath. Or through maven dependency:
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>jul-to-slf4j</artifactId>
<version>1.7.0</version>
</dependency>
If you don't have logging.properties (for java.util.logging), add this to your bootstrap code:
SLF4JBridgeHandler.removeHandlersForRootLogger();
SLF4JBridgeHandler.install();
If you have logging.properties (and want to keep it), add this to it:
handlers = org.slf4j.bridge.SLF4JBridgeHandler
In order to avoid performance penalty, add this contextListener to logback.xml (as of logback version 0.9.25):
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<contextListener class="ch.qos.logback.classic.jul.LevelChangePropagator">
<!-- reset all previous level configurations of all j.u.l. loggers -->
<resetJUL>true</resetJUL>
</contextListener>
...
</configuration>

Using log4j on Google App Engine

I need to use log4j in my application, but I don't know how I can get properties loaded. Deafult properties files says that I should put log4j.properties to /WEB-INF/classes/ folder, but in eclipse I cannot see that folder and I cannot create it, because it already exists. And I cannot add any files to that folder either.
Here is error that I get:
log4j:WARN No appenders could be found for logger (DataNucleus.ClassLoading).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
So how can I get web application to load log4j properties?

Put the log4j.properties file into a source directory of your project, e.g. /src. Eclipse will copy it into your target build directory.
I recomend using SLF4J with Log4J, and the SpringSource Tool Suite (STS) for your project.

Here is how to get log4j working using Eclipse with the Google plugin.
Modify appengine-web.xml as follows:
<system-properties>
<property name="java.util.logging.config.file" value="WEB-INF/classes/log4j.properties"/>
</system-properties>
You can add the following code to your servlet:
import org.apache.log4j.Logger;
...
Logger logger = Logger.getLogger("com.foo");
logger.debug("Yay2!");
Put the log4j.properties file in the src/ directory with the following content:
log4j.rootLogger=DEBUG, stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p %t %c{1}:%M:%L - %m%n
You can do a Project > Clean then allow it to automatically build, The build copies the log4j.properties file to /war/WEB-INF/classes/. You'll see the log displayed when you Run As > Web Application and request a URL.
I know that you're not using Maven but I will add instructions below in case anyone else needs them. These instructions will work with com.google.appengine.archetypes:guestbook-archetype.
Add the following to pom.xml:
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.16</version>
</dependency>
Add the following code to guestbook.jsp:
<%# page import="org.apache.log4j.Logger" %>
...
<%
Logger logger = Logger.getLogger("com.foo");
logger.debug("Yay2!");
%>
Create src/main/webapp/WEB-INF/classes/log4j.properties with the same content as above.
Then run:
mvn clean
mvn verify
mvn appengine:devserver
You will see log output in our console after calling http://localhost:8080/.

I have to put the log4j.properties and then configured in web.xml:
<listener>
<listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
</listener>
<context-param>
<param-name>log4jConfigLocation</param-name>
<param-value>/WEB-INF/log4j.properties</param-value>
</context-param>
That way it runs before the classpath loading and it works.
Although it doesn't send the JUL stuff to log4j, so you will need a separated configuration to do that.

Ignore everything you see in the internet for the keywords spring + log4j + appengine.
The solution that worked for me and didn't created ambiguity was to leave JUL be and configure log4j with spring separately in this way:
public class CustomXmlWebApplicationContext extends XmlWebApplicationContext {
#Override
protected void initBeanDefinitionReader(XmlBeanDefinitionReader beanDefinitionReader) {
super.initBeanDefinitionReader(beanDefinitionReader);
try {
Resource res = beanDefinitionReader.getResourceLoader().getResource("classpath:log4j.properties");
Properties props = new Properties();
props.load(res.getInputStream());
PropertyConfigurator.configure(props);
}
catch(Throwable e) {
e.printStackTrace();
}
}
}
Then just put your log4j.properties in the root of your source folder.

There is a good article on Logging in the Google AppEngine for Java (GAE/J) with Slf4j, Log4j and JUL.
In \src\main\webapp\WEB-INF\appengine-web.xml you need to have
appengine-web.xml
<!-- Configure java.util.logging -->
<system-properties>
<property name="java.util.logging.config.file" value="WEB-INF/java-util-logging.properties"/>
</system-properties>
to tell GAE where java.util.logging (JUL) is configured.
In \src\main\webapp\WEB-INF\java-util-logging.properties you need
java-util-logging.properties
.level = ALL
or another of the JUL level names, as you like (i.e. 'TRACE' does not work).
In \src\main\resources\log4j.properties file you will have
log4j.properties
log4j.rootLogger=ALL, stdout
# or a lower log level such as DEBUG, INFO or WARN.
# Define the destination and format of our logging
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%-5p: %m at %C.(%F:%L) on %d{ISO8601}%n
You need to add log4j to your CLASSPATH. I use Gradle for dependency management, so here is my build script:
build.gradle
configurations {
all*.exclude group: "commons-logging", module: "commons-logging"
}
dependencies {
// Logging
compile 'org.slf4j:slf4j-api:1.7.+'
runtime 'org.slf4j:slf4j-jdk14:1.7.+'
runtime ('log4j:log4j:1.2.17') {
exclude group: "com.sun.jdmk", module: "jmxtools"
exclude group: "com.sun.jmx", module: "jmxri"
exclude group: "javax.mail", module: "mail"
exclude group: "javax.jms", module: "jms"
}
}
If you are using Spring WebMVC, in order to provide a Log4J configuration file when starting up your application add the following listener to your Deployment descriptor.
web.xml
<!-- The definition of the Log4j Configuration -->
<listener>
<listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
</listener>
<context-param>
<param-name>log4jConfigLocation</param-name>
<param-value>/WEB-INF/log4j.properties</param-value>
</context-param>