<div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr">Thank you Ceki for your response.<br><br>But this is not an answer. I have already seen the doc. There are nothing about this issue!<br>The version of commons-logging is - 1.1.3, but Log4JLogger is present in 1.1.1 library too.<br>Log4JLogger is just an implementation of Log interface. Not sure why it is missing in jcl-over-slf4j library.<br><br>I have created the Jira ticket for it:<br><a href="https://jira.qos.ch/browse/SLF4J-443">https://jira.qos.ch/browse/SLF4J-443</a><br><br><br>On 06.09.2018 22:20, Ceki wrote:<br>> Hi Vitalii,<br>><br>> Please see the docs on jcl-over-slf4j.jar available at<br>><br>>  <a href="https://www.slf4j.org/legacy.html#jclOverSLF4J" rel="noreferrer" target="_blank">https://www.slf4j.org/legacy.html#jclOverSLF4J</a><br>><br>> Best regards,<br>> --<br>> Ceki<br><br><br></div></div></div></div><br><div class="gmail_quote"><div dir="ltr">On Thu, Sep 6, 2018 at 10:29 PM Vitalii Diravka <<a href="mailto:vitalii@apache.org">vitalii@apache.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><font size="3">Hi all!<br><br>I working on updating hadoop libraries in Apache Drill project.<br>hadoop-hdfs uses commons-logging library, but Drill uses jcl-over-slf4j and bans commons-logging.<br><br>I faced the following issue:<br>java.lang.NoClassDefFoundError: org/apache/commons/logging/impl/Log4JLogger [1]<br>I even didn't find this class with the same path in any slf4j library. <br><br>Is that possible to solve the issue without enabling commons-logging in Drill project? Looks like Log4JLogger class in org.apache.commons.logging.impl of </font><span style="font-size:medium">jcl-over-slf4j [2] </span><span style="font-size:medium">could resolve it. Should it be there? But </span><span style="font-size:medium">then </span><span style="font-size:medium">it will be the question to the dev list.<br><br>[1] </span><font size="3"><a href="https://github.com/apache/hadoop/blob/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/common/MetricsLoggerTask.java#L152" target="_blank">https://github.com/apache/hadoop/blob/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/common/MetricsLoggerTask.java#L152</a><br>[2] <a href="https://github.com/qos-ch/slf4j/tree/master/jcl-over-slf4j/src/main/java/org/apache/commons/logging/impl" target="_blank">https://github.com/qos-ch/slf4j/tree/master/jcl-over-slf4j/src/main/java/org/apache/commons/logging/impl</a></font></div><div dir="ltr"><font size="3"><br></font><span style="font-size:medium">Thanks</span><font size="3"><br></font></div></div></div></div></div></div></div></div>
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