log4j conflicting? - java

I have a htmlunit application and I turned off its logging by the following lines since it was printing way too many messages in the console which I don't need.
LogFactory.getFactory().setAttribute(
"org.apache.commons.logging.Log",
"org.apache.commons.logging.impl.NoOpLog");
java.util.logging.Logger.getLogger("com.gargoylesoftware.htmlunit")
.setLevel(Level.OFF);
java.util.logging.Logger.getLogger("org.apache.commons.httpclient")
.setLevel(Level.OFF);
I then added the latest log4j jar to my project and configured it so I can have my own custom logging messages. But now everything from htmlunit also goes to my log file. How can I prevent this? I only want my own logging messages to go to the log file.

One important thing to understand about log4j is its concept of a 'logger hierarchy', and how this affects its settings. To quote the log4j documentation,
A logger is said to be an ancestor of another logger if its name followed by a dot is a prefix of the descendant logger name. A logger
is said to be a parent of a child logger if there are no ancestors
between itself and the descendant logger.
For example, the logger named "com.foo" is a parent of the logger
named "com.foo.Bar". Similarly, "java" is a parent of "java.util" and
an ancestor of "java.util.Vector". This naming scheme should be
familiar to most developers.
A logger inherits the settings of its parent, and the 'root logger' is always at the top of the hierarchy. Therefore to some extent you can treat the root logger as the 'default' logger settings, and you can then add to these settings for just the loggers contained in your code.
I don't know how to set this up in code, but here is what I would do using a log4j.properties file:
# Direct log messages to a log file
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.File=logs/springapp.log
log4j.appender.file.MaxFileSize=1MB
log4j.appender.file.MaxBackupIndex=1
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n
# Direct log messages to console
log4j.appender.console=org.apache.log4j.ConsoleAppender
log4j.appender.console.Target=System.out
log4j.appender.console.layout=org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n
# Root logger settings: by default only log messages at level "ERROR" and above
# will be logged. These messages will be written to console
log4j.rootLogger=error, console
# All loggers with names starting with "org.somecompany.someproject"
# will log messages at all levels "DEBUG" and above.
# They will be written to file as well as console; writing to console
# is enabled since that setting is inherited from the root logger.
log4j.logger.org.somecompany.someproject=debug, file
Then, assuming that the logger of each class is named as the fully qualified name of that class, then simply replace "org.somecompany.someproject" in the above config with the root package name for the packages in your project, and that should give you the behaviour you want.
For more information, have a look at the log4j documentation.

Related

Set JCS log level to ERROR - log4j

I have implemented JCS in my J2ee application which uses log4j for logging.
My Requirement
Set the application rootLogger in DEBUG level and jcs logs in ERROR mode.
What is tried
Tried the following in log4j properties
log4j.category.org.apache.common.jcs=ERROR
log4j.logger.org.apache.common.jcs=ERROR
But nothing is affecting the logging.
Whenever the cache access happens, it logs a bunch of returning first node messages.
Note : I am using the latest JCS commons-jcs-core-2.0-beta-1.jar
This is my complete log4j.properties
log4j.rootLogger=DEBUG, A1
# Use Console Appender for development
log4j.appender.A1=org.apache.log4j.ConsoleAppender
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
log4j.appender.A1.layout.ConversionPattern= %d [%t] %-5p - %m%n
log4j.logger.net.sf.jasperreports=ERROR
log4j.category.org.apache.common.jcs=ERROR
I missed an "s" in commons. Correcting it solved my problem.
Solution
Both the below statements can be used to configure JCS log level in log4j.
log4j.category.org.apache.commons.jcs=ERROR
log4j.logger.org.apache.commons.jcs=ERROR
JCS has a dependency on commons-logging for logging, and not log4j. Hence, log4j configurations won't matter unless you redirect commons-logging to log4j. To do that, create a file named commons-logging.properties and add the following in that.
org.apache.commons.logging.Log=org.apache.commons.logging.impl.Log4jLogger

restrict logs using log4j

I'm using log4j for logging, and it is the first time I'm working on it.
I want to log particular lines from the code, say for exmple
log.debug("this is my an example");
Only want these lines from my project in my log file. Is it possible using log4j?
Here is my log4j.properties
log4j.rootLogger=DEBUG, CA
log4j.appender.CA =org.apache.log4j.RollingFileAppender
log4j.appender.CA.layout=org.apache.log4j.PatternLayout
log4j.appender.CA.File=myLocation/logs.log
log4j.appender.CA.ImmediateFlush=true
log4j.appender.CA.Append=false
log4j.appender.CA.layout.ConversionPattern= %d{ABSOLUTE} %5p %c - %m%n
aslo can we route the logging to separate file for each run?
Set loglevel in your code as below and make it as a static block or something where it should load at the startup
private static org.apache.log4j.Logger log = Logger.getLogger(LogClass.class);
log.setLevel(Level.Debug);
and for specific package restrictions of log, you can do like below
Suppose you have a package a.b.c
To specify logging level for this package as debug, add the below line in your log4j.properties
log4j.logger.a.b.c=debug

Log4j doesn't log INFO Level

I have the following log4j.properties file, for an application deployed in WebSphere Portal:
log4j.rootLogger=DEBUG, InfoAppender, DebugAppender
log4j.appender.InfoAppender=org.apache.log4j.RollingFileAppender
log4j.appender.InfoAppender.Threshold=INFO
log4j.appender.InfoAppender.File=C:/info.log
log4j.appender.InfoAppender.layout=org.apache.log4j.PatternLayout
log4j.appender.InfoAppender.layout.ConversionPattern=%d %p [%c] - %m%n
log4j.appender.DebugAppender=org.apache.log4j.RollingFileAppender
log4j.appender.DebugAppender.Threshold=DEBUG
log4j.appender.DebugAppender.File=C:/debug.log
log4j.appender.DebugAppender.layout=org.apache.log4j.PatternLayout
log4j.appender.DebugAppender.layout.ConversionPattern=%d %p [%c] - %m%n
When I code, I define the logger at class level:
private static Logger logger = Logger.getLogger(IWannaLogThis.class);
And I log INFO messages with this:
logger.info(theObjectToLog);
When I deploy my application, the debug.log file gets everything I log with logger.debug() but ignores everything I write with logger.info(). On the other side, the info.log file keeps empty.
The weirdest thing is that in debug.log and info.log appears some INFO and DEBUG messages made by some JARS (like Hibernate Validator) I had in the classpath, but just ignores everything I try to log in my code.
Any ideas?
This is most likely a classloading-related problem. WebSphere Portal uses Log4J internally, so I'm guessing that you end up using WebSphere Portal's provided Log4J JAR file as well as its own Log4J properties.
You can verify that by adding the following to the JVM arguments of the server instance:
-Dlog4j.debug=true
And then inspect the SystemOut.log file. Log4J will spit out lots of tracing information about the configuration file(s) it reads.
The best way to avoid this is to do the following:
Bundle the Log4J JAR file with your application.
Associate a Shared Library with the server. In that Shared Library, place your Log4J configuration file.
As an alternative to step 2, you can bundle your Log4J configuration file with the application itself, however that would carry its own drawbacks (for example, having to repackage your application whenever you perform a Log4J configuration change).
Another common problem is that the JARs you have in your classpath also use log4j and also have their own appenders set. So depending on the settings that they use, and the packages that your classes reside in, this may lead to the problem you describe.
So:
Make sure that your package names are unique and not used by any of the third party libraries.
Check the log4j settings in all libraries in your classpath. They should not contain general settings which override yours.
Make sure your loggers use your log4j.properties (you can be sure if changes you make in your file affect your loggers as expected).
If you can, make sure that your log4j stuff loads last, in case any of the third party libs reset the configuration. They shouldn't, but who can stop them.
Normally, it should be one of these things. Post more explicit example if it doesn't work.
Good luck!
What I have done in the past is set specific logs for the classes I want to log. It sounds like you can try setting your root logger to INFO and see if that gets you the messages you want. Here's a little bit of my log4j property file. I set a logger for each class and assign it to my "data" appender, which defines the log layout. In the loggers I specify specific classes I want to log and set their Log level individually. Any class that logs that is not defined in the Loggers I have use the default log level for the rootCategory.
log4j.rootCategory=INFO, rollingFile, stdout
#GetData Loggers
log4j.logger.com.myapp.data=INFO, data
log4j.logger.com.myapp.data.SybaseConnection=DEBUG, data
log4j.logger.com.myapp.data.GetData=ERROR, data
# data appender
log4j.appender.data=org.apache.log4j.RollingFileAppender
log4j.appender.data.layout=org.apache.log4j.PatternLayout
log4j.appender.data.File=c\:\\Program Files\\MyApp\\logs\\MyApp-data.log
log4j.appender.data.Append=true
log4j.appender.data.layout.ConversionPattern=[%d{ISO8601}]%5p%6.6r[%t]%x - %C.%M(%F:%L) - %m%n
you root logger opens the log properties in the debug mode,
use INFO instead of DEbug in the first line of your properties file.

No appenders could be found for logger(log4j)?

I have put log4j to my buildpath, but I get the following message when I run my application:
log4j:WARN No appenders could be found for logger (dao.hsqlmanager).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
What do these warnings mean? Whats the appender here?
This Short introduction to log4j guide is a little bit old but still valid.
That guide will give you some information about how to use loggers and appenders.
Just to get you going you have two simple approaches you can take.
First one is to just add this line to your main method:
BasicConfigurator.configure();
Second approach is to add this standard log4j.properties (taken from the above mentioned guide) file to your classpath:
# Set root logger level to DEBUG and its only appender to A1.
log4j.rootLogger=DEBUG, A1
# A1 is set to be a ConsoleAppender.
log4j.appender.A1=org.apache.log4j.ConsoleAppender
# A1 uses PatternLayout.
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
log4j.appender.A1.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n
It looks like you need to add the location of your log4j.properties file to the Classpath in Eclipse.
Make sure your project is open in Eclipse, then click on the "Run" menu at the top of Eclipse and click on the following:
Run
Run Configurations
Classpath (tab)
User Entries
Advanced (button on the right)
Add Folders
then navigate to the folder that contains your log4j.properties file
Apply
Run
The error message should no longer appear.
Quick solution:
add code to main function:
String log4jConfPath = "/path/to/log4j.properties";
PropertyConfigurator.configure(log4jConfPath);
create a file named log4j.properties at /path/to
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{yy/MM/dd HH:mm:ss} %p %c{2}: %m%n
This is just a warning.
Fixing
This occurs when the default configuration files log4j.properties and log4j.xml can not be found and the application performs no explicit configuration.
To fix that, simply create/copy log4j.properties or log4j.xml into your a location on the classpath (usually the same as the jar files).
Optionally set java option: -Dlog4j.configuration=file:///path/to/log4j.properties.
log4j uses Thread.getContextClassLoader().getResource() to locate the default configuration files and does not directly check the file system. Knowing the appropriate location to place log4j.properties or log4j.xml requires understanding the search strategy of the class loader in use. log4j does not provide a default configuration since output to the console or to the file system may be prohibited in some environments.
Debugging
For debugging, you may try to use -Dlog4j.debug=true parameter.
Configuration of log4j.properties
Sample configuration of log4j.properties:
# Set root logger level to DEBUG and its only appender to A1.
log4j.rootLogger=DEBUG, A1
# A1 is set to be a ConsoleAppender.
log4j.appender.A1=org.apache.log4j.ConsoleAppender
# A1 uses PatternLayout.
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
log4j.appender.A1.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n
# Print only messages of level WARN or above in the package com.foo.
log4j.logger.com.foo=WARN
Here is another configuration file that uses multiple appenders:
log4j.rootLogger=debug, stdout, R
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
# Pattern to output the caller's file name and line number.
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] (%F:%L) - %m%n
log4j.appender.R=org.apache.log4j.RollingFileAppender
log4j.appender.R.File=example.log
log4j.appender.R.MaxFileSize=100KB
# Keep one backup file
log4j.appender.R.MaxBackupIndex=1
log4j.appender.R.layout=org.apache.log4j.PatternLayout
log4j.appender.R.layout.ConversionPattern=%p %t %c - %m%n
Apache Solr
If using Solr, copy <solr>/example/resources/log4j.properties into a location on the classpath.
Sample configuration of log4j.properties from Solr goes like:
# Logging level
solr.log=logs/
log4j.rootLogger=INFO, file, CONSOLE
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%-4r [%t] %-5p %c %x \u2013 %m%n
#- size rotation with log cleanup.
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.MaxFileSize=4MB
log4j.appender.file.MaxBackupIndex=9
#- File to log to and log format
log4j.appender.file.File=${solr.log}/solr.log
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%-5p - %d{yyyy-MM-dd HH:mm:ss.SSS}; %C; %m\n
log4j.logger.org.apache.zookeeper=WARN
log4j.logger.org.apache.hadoop=WARN
# set to INFO to enable infostream log messages
log4j.logger.org.apache.solr.update.LoggingInfoStream=OFF
See also:
Short introduction to log4j: Default Initialization Procedure
Why can't log4j find my properties in a J2EE or WAR application?
Most of the answers here suggested that log4j.properties file be placed in the right location(for maven project, it should be located in src/main/resources)
But for me, the problem is that my log4j.properties is not correctly configured. Here's a sample that works for me, you can try it out first.
# Root logger option
log4j.rootLogger=INFO, stdout
# Direct log messages to 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
As explained earlier there are 2 approaches
First one is to just add this line to your main method:
BasicConfigurator.configure();
Second approach is to add this standard log4j.properties file to your classpath:
While taking second approach you need to make sure you initialize the file properly,
Eg.
Properties props = new Properties();
props.load(new FileInputStream("log4j property file path"));
props.setProperty("log4j.appender.File.File", "Folder where you want to store log files/" + "File Name");
Make sure you create required folder to store log files.
You use the Logger in your code to log a message. The Appender is a Object appended to a Logger to write the message to a specific target. There are FileAppender to write to text-files or the ConsoleAppender to write to the Console. You need to show your code of the Logger and Appender setup for more help.
please read the tutorial for a better understanding of the interaction of Logger and Appender.
Make sure the properties file has properly set.
And again, it seems like that the compiler cannot find the properties file, you can set as follow at the pom (only when you use maven project).
<build>
<sourceDirectory> src/main/java</sourceDirectory>
<testSourceDirectory> src/test/java</testSourceDirectory>
<resources>
<resource>
<directory>resources</directory>
</resource>
</resources>
</build >
I get the same error. Here the problem which leads to this error message:
I create some objects which use the Logger before I configure the log4j:
Logger.getLogger(Lang.class.getName()).debug("Loading language: " + filename);
Solution:
Configure the log4j at the beginning in the main method:
PropertyConfigurator.configure(xmlLog4JConfigFile);
// or BasicConfigurator.configure(); if you dont have a config file
Add the following as the first code:
Properties prop = new Properties();
prop.setProperty("log4j.rootLogger", "WARN");
PropertyConfigurator.configure(prop);
I faced the same issue when I tried to run the JUnit test class.
The issue is resolved after I manually added the log4j.properties file in the src/test/resources folder.
Adding the below code to the log4j.properties file solved the issue:
# Root logger option
log4j.rootLogger=INFO, file, stdout
# Direct log messages to a log file
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.File=C:\\logging.log
log4j.appender.file.MaxFileSize=10MB
log4j.appender.file.MaxBackupIndex=10
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
# Direct log messages to 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
I think you should understand where the log4j jar file or the Java code looks for the log4j configuration files.
src/main/resources/log4j.properties is Eclipse path.
Place them in a proper location so that you don't have to hard code the absolute path in code.
Read my article and sample solution for that
https://askyourquestions.info/how-to-see-where-the-log-is-logger-in-slf4j/
First of all: Create a log4j.properties file
# Root logger option
log4j.rootLogger=INFO, stdout
# Direct log messages to 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
Place it in src/main/resources/
After that, use this 2 dependencies:
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.5</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.5</version>
</dependency>
It is necessary to add this final dependency to POM file:
<!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>5.1.5.RELEASE</version>
</dependency>
In my case, the error was the flag "additivity". If it's "false" for you root project package, then the child packages will not have an appender and you will see the "appender not found" error.
Another reason this may happen (in RCP4) is that you are using multiple logging frameworks in your target file. As an example, this will occur if you use a combination of slf4j, log4j and ch.qos.logback.slf4j in your target files content tab.
If you are using Eclipse and this problem appeared out of nowhere after everything worked fine beforehand, try going to Project - Clean - Clean.
I ran into this issue when trying to build an executable jar with maven in intellij 12. It turned out that because the java manifest file didn't include a class path the log4j properties file couldn't be found at the root level (where the jar file was executed from.)
FYI I was getting the logger like this:
Logger log = LogManager.getLogger(MyClassIWantedToLogFrom.class);
And I was able to get it to work with a pom file that included this:
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<version>2.2-beta-5</version>
<configuration>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<mainClass>com.mycompany.mainPackage.mainClass</mainClass>
</manifest>
<manifestEntries>
<Class-Path>.</Class-Path> <!-- need to add current directory to classpath properties files can be found -->
</manifestEntries>
</archive>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
</configuration>
<executions>
<execution>
<id>make-assembly</id>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
</plugin>
Make sure your project is open in Eclipse, then click on the "Run" menu at the top of Eclipse and click on the following:
Run
Run Configurations
Classpath (tab)
User Entries
add jar on the right
add log4j jar file
Apply
Run
The error message should no longer appear.
The reason can be lack of the word static in some:
final static Logger logging = Logger.getLogger(ProcessorTest.class);
If I make logger the instance field, I am getting exactly this very warning:
No appenders could be found for logger (org.apache.kafka.producer.Sender)
What is worse, the warning points not to ProcessorTest, where the mistake lives, but to an absolutely different class (Sender) as a source of problems. That class has correct set logger and need not any changes! We could look for the problem for ages!
I faced the same problem when I use log4j2. My problem is caused by using wrong dependent library:
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<scope>runtime</scope>
</dependency>
Instead, I should use:
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-slf4j-impl</artifactId>
<scope>runtime</scope>
</dependency>
In my case, I have a log4j2.xml defined in my "resources" directory, and specified to use it by:
System.setProperty("log4j.configurationFile", "log4j2.xml");
Log4J display this warning message when Log4j Java code is searching to create a first log line in your program.
At this moment, Log4j make 2 things
it search to find log4j.properties file
it search to instantiate the appender define in log4j.properties
If log4J doesn't find log4j.properties file or if appender declared in log4j.rootlogger are not defined elsewhere in log4j.properties file the warning message is displayed.
CAUTION: the content of Properties file must be correct.
The following content is NOT correct
log4j.rootLogger=file
log4j.appender.FILE=org.apache.log4j.FileAppender
log4j.appender.FILE.File=c:/Trace/MsgStackLogging.log
log4j.appender.FILE.layout=org.apache.log4j.PatternLayout
log4j.appender.FILE.layout.ConversionPattern=%m%n
log4j.appender.FILE.ImmediateFlush=true
log4j.appender.FILE.Threshold=debug
log4j.appender.FILE.Append=false
because file appender is declared in LOWER-CASE in log4j.rootlogger statement and defined in log4j.appender statement using UPPER-CASE !
A correct file would be
log4j.rootLogger=FILE
log4j.appender.FILE=org.apache.log4j.FileAppender
log4j.appender.FILE.File=c:/Trace/MsgStackLogging.log
log4j.appender.FILE.layout=org.apache.log4j.PatternLayout
log4j.appender.FILE.layout.ConversionPattern=%m%n
log4j.appender.FILE.ImmediateFlush=true
log4j.appender.FILE.Threshold=debug
log4j.appender.FILE.Append=false
If MAVEN is used, you must put log4j.properties files in src/main/resources AND start a MAVEN build.
Log4j.properties file is then copied in target/classes folder.
Log4J use the log4j.properties file that it found in target/classes !
I had this problem too.
I just forgot to mark the resources directory in IntelliJ IDEA
Rightclick on your directory
Mark directory as
Resources root
For me, the reason was apparently different, and the error message misleading.
With just this in my build.gradle, it would complain that slf4j was missing at the beginning of the log, but still log things, albeit in a poor format:
compile 'log4j:log4j:1.2.17'
Adding that dependency would cause the discussed "no appenders could be found" error message for me, even though I had defined them in src/main/java/log4j.properties:
compile 'log4j:log4j:1.2.17'
compile 'org.slf4j:slf4j-log4j12:1.7.25'
Finally, adding the following dependency (which I only guessed at by copycatting it from another project) resolved the issue:
compile 'log4j:log4j:1.2.17'
compile 'org.slf4j:slf4j-log4j12:1.7.25'
compile 'commons-logging:commons-logging:1.2'
I don't know why, but with this it works. Any insights on that?
My Eclipse installation could not find log4j.properties when running JUnit tests from Eclipse, even though the file was located at src/test/resources.
The reason was that Eclipse (or the m2e connector) did not copy content from src/test/resources to the expected output folder target/test-classes - the root cause was that in the project's properties under Java Build Path -> Source tab -> Source folders on build path -> src/test/resources, somehow there was an Excluded: ** entry. I removed that excluded entry.
Alternatively, I could have manually copied src/test/resources/log4j.properties to target/test-classes/log4j.properties.
If log4j.properties is indeed on the classpath, you are using Spring Boot to make a WAR file for deployment to an app server, you are omitting a web.xml file in favour of Spring Boot's autoconfigure, and you are not getting any log messages whatsoever, you need to explicitly configure Log4j. Assuming you are using Log4j 1.2.x:
public class AppConfig extends SpringBootServletInitializer {
public static void main( String[] args ) {
// Launch the application
ConfigurableApplicationContext context = SpringApplication.run( AppConfig.class, args );
}
#Override
protected SpringApplicationBuilder configure( SpringApplicationBuilder application ) {
InputStream log4j = this.getClass().getClassLoader().getResourceAsStream("log4j.properties");
PropertyConfigurator.configure(log4j);
return application;
}
// Other beans as required...
}
Maybe add the relevent project contains log4j in java build path, I add mahout_h2o into it when I met this problem in a mahout project using eclipse, it works!
if you work together with a lot of projects you may face a style problem.
*you have to have one lof4j.properties file and this file is included log properties of other project.
*Beside you can try to put log4j properties files into src path when the project is worked Linux OS, libs of other project and log4.properties files can be under one folder into a location on the classpath.
First import:
import org.apache.log4j.PropertyConfigurator;
Then add below code to main method:
String log4jConfPath ="path to/log4j.properties";
PropertyConfigurator.configure(log4jConfPath);
Create a file at path to and add the below code to that file.
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{yy/MM/dd HH:mm:ss} %p %c{2}: %m%n
The solution on this site worked for me https://crunchify.com/java-how-to-configure-log4j-logger-property-correctly/. I now see no warnings at all from log4j
I put this in a log4j.properties file that I put in src/main/resources
# This sets the global logging level and specifies the appenders
log4j.rootLogger=INFO, theConsoleAppender
# settings for the console appender
log4j.appender.theConsoleAppender=org.apache.log4j.ConsoleAppender
log4j.appender.theConsoleAppender.layout=org.apache.log4j.PatternLayout
log4j.appender.theConsoleAppender.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n
Consider the log4j JVM argument Dlog4j.configuration
In general:
Add the JVM argument that points out the log4j config file.
The syntax is just like follows:
java [ options ] -jar file.jar [ arguments ]
A sample of a real command line is just like the following:
java -Dlog4j.configuration=conf/log4j.xml -jar myJarFile.jar myArg1 myArg2
For IntelliJ IDE users:
1.Run/Debug Configurations
2.Edit configurations...
3.VM options
4.Enter the same value also starting with "-D"
Tips:
1.Eclipse IDE users will find an equivalent approach
2.For the run/debug configuration editor, it's very likely that, at the beginning of the times, your particular executable file is not there. Depending on the size of the project you're currently working on, it can be unpleasant to navigate directories to find it. It's less of a hassle if you just run/execute the file (click play) once before proceeding to run/debug config no matter what the execution result is.
3.Pay attention to your working directory, relative paths, and classpath.

log4j warning issue - apache commons

I'm using apache commons library and log4j.
I have an xml configuration file and a log4j.properties files. I want to specify my log4j properties path inside my xml configuration file.
To load my settings i do:
//Loading my xml file
this.config = new XMLConfiguration(this.xmlFileName);
At this moment the following warnings are raised:
log4j:WARN No appenders could be found for logger (org.apache.commons.configuration.ConfigurationUtils).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
However i haven't yet called any log4j object. Once i have read the xml file i can successfully work with my log4j instance.
Is there any way to remove those warnings?
Check if the log4j.properties file is in the classpath
This link might be useful:
http://www.coderanch.com/t/63230/open-source/log-log-WARN-No-appenders
Log4J outputs this error when a logger is created, but no appender(s) is(are) defined.
In practice this error occurs when a logger is created before log4j is initialized.
You say you haven't called any log4j object. But in the error message you see that org.apache.commons.configuration.ConfigurationUtils creates a logger object (see line 66).
You could turn it off before initialization, see How to turn off log4j warnings?
Logger.getRootLogger().setLevel(Level.OFF);
There should be no need to turn it on again since the initialization sets normally the log level of the root logger.
You should at least set the appender and the logger level for the root logger in the loaded log4j configuration file. Otherwise , you will see this warning message.
Example of setting the appender and logger level for the root logger:
#Set root logger 's level and its appender to an appender called CONSOLE which is defined below.
log4j.rootLogger=DEBUG, CONSOLE
#Set the behavior of the CONSOLE appender
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%d [%t] %-5p %c - %m%n
I resolve my issue with this workaround:
//Disable log level
Logger.getRootLogger().setLevel(Level.OFF);
Now i can read my xml configuration file without WARNINGS.
After set log level:
Logger.getRootLogger().setLevel(Level.INFO);

Categories