Log4j No logging applications found (org.apache.hadoop.util.shell)

Question

I am using maven for my project. When I run the program, I get this error, and because of this I do not see the execution of the program, although the program produces the expected results.

srimanth@srimanth-Inspiron-N5110 :~/CCHD&CCHA/mangoes$ mvn exec:java -q -Dexec.mainClass=bananas.MapReduceColorCount -Dexec.args="hdfs://localhost:9000/users.avrofile hdfs://localhost:9000/pleaseatleastnow6" log4j:WARN No appenders could be found for logger (org.apache.hadoop.util.Shell). log4j:WARN Please initialize the log4j system properly. log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info. srimanth@srimanth-Inspiron-N5110 :~/CCHD&CCHA/mangoes$ 

Here is my pom.xml

 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>fruits</groupId> <artifactId>mangoes</artifactId> <version>0.0.1-SNAPSHOT</version> <name>Hadoop</name> <description>Hadoop Hadoop</description> <dependencies> <dependency> <groupId>org.apache.avro</groupId> <artifactId>avro</artifactId> <version>1.7.6</version> </dependency> <dependency> <groupId>org.apache.avro</groupId> <artifactId>avro-mapred</artifactId> <version>1.7.6</version> <classifier>hadoop2</classifier> </dependency> <dependency> <groupId>org.apache.hadoop</groupId> <artifactId>hadoop-yarn-api</artifactId> <version>2.6.0</version> </dependency> <dependency> <groupId>org.apache.hadoop</groupId> <artifactId>hadoop-common</artifactId> <version>2.6.0</version> </dependency> <dependency> <groupId>org.apache.hadoop</groupId> <artifactId>hadoop-hdfs</artifactId> <version>2.6.0</version> </dependency> <dependency> <groupId>org.apache.hadoop</groupId> <artifactId>hadoop-mapreduce-client-app</artifactId> <version>2.6.0</version> </dependency> <dependency> <groupId>org.apache.hadoop</groupId> <artifactId>hadoop-mapreduce-client-common</artifactId> <version>2.6.0</version> </dependency> <dependency> <groupId>org.apache.hadoop</groupId> <artifactId>hadoop-yarn-client</artifactId> <version>2.6.0</version> </dependency> <dependency> <groupId>org.apache.hadoop</groupId> <artifactId>hadoop-client</artifactId> <version>2.6.0</version> </dependency> <dependency> <groupId>org.apache.hadoop</groupId> <artifactId>hadoop-mapreduce-client-core</artifactId> <version>2.6.0</version> </dependency> <dependency> <groupId>org.apache.hadoop</groupId> <artifactId>hadoop-yarn-common</artifactId> <version>2.6.0</version> </dependency> </dependencies> <build> <pluginManagement> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>3.3</version> <configuration> <source>1.7</source> <target>1.7</target> </configuration> </plugin> <plugin> <groupId>org.apache.avro</groupId> <artifactId>avro-maven-plugin</artifactId> <version>1.7.6</version> <executions> <execution> <phase>generate-sources</phase> <goals> <goal>schema</goal> </goals> <configuration> <sourceDirectory>${project.basedir}/../</sourceDirectory> <outputDirectory>${project.basedir}/target/generated-sources/</outputDirectory> </configuration> </execution> </executions> </plugin> </plugins> </pluginManagement> </build> </project> 

Am I missing any addiction? How / Where can I configure log4j correctly. Thank you in advance. I would appreciate help.

Answer 1

For Maven, you must place the log4j.properties or log4j.xml file in the main / resources folder. this is. nothing else to do. Create your own properties file. Something like that.

 log4j.rootLogger=DEBUG, CA log4j.appender.CA=org.apache.log4j.ConsoleAppender log4j.appender.CA.layout=org.apache.log4j.PatternLayout log4j.appender.CA.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n 

You can specify INFO, ERROR, WARNING, FATAL and DEBUG for the log4j.rootlogger property. replace the debugging system depending on which log mode is best suited to your needs.

Answer 2

Follow the URL provided in the warning. This will provide some guidance.

 http://logging.apache.org/log4j/1.2/faq.html#noconfig 

From the site:

This occurs when the default configuration files log4j.properties and log4j.xml cannot be found, and the application does not perform any explicit configurations. log4j uses Thread.getContextClassLoader (). getResource () find the default configuration files and do not scan the file system directly. Knowing the appropriate place to host log4j.properties or log4j.xml requires an understanding of the search strategy of the loader class used. log4j does not provide a default configuration value, since output to the console or to the file system may be prohibited in some environments.

You need either log4j.properties or log4j.xml . Build either the one that suits you best. Read Log4J manua l will give you some knowledge to help create a configuration file