fapifta opened a new pull request #2965: URL: https://github.com/apache/hadoop/pull/2965
As stated in this article: https://www.infoworld.com/article/2077344/find-a-way-out-of-the-classloader-maze.html A native thread has its context classloader set to null by default. If the context classloader which is used internally by JNDI to load a class is null, then the bootstrap classloader is used, according to the apidoc here: https://docs.oracle.com/javase/8/docs/api/java/lang/Class.html#forName-java.lang.String-boolean-java.lang.ClassLoader- JNDI uses this form with the context classloader as can be seen here: https://github.com/openjdk/jdk11u/blob/master/src/java.naming/share/classes/com/sun/jndi/ldap/VersionHelper.java#L107 or here: https://github.com/openjdk/jdk8u/blob/master/jdk/src/share/classes/com/sun/jndi/ldap/VersionHelper12.java#L72 In Impala this call happens from a Thread created in native space, so in that case, the System/Application classloader loads LdapSslSocketFactory fine in LdapGroupsMapping.getDirContext() while creating the environment, but then InitialDirContext constructor gets to instantiation the LdapSslSocketFactory inside JNDI with the help of the linked VersionHelper impelmentations, and fails to load the class with the bootstrap classloader as context classloader is null. In order to solve this problem, we can safely use the classloader of the LdapGroupsMapping class, as it had to load the LdapSslSocketFactory class before. ## NOTICE Please create an issue in ASF JIRA before opening a pull request, and you need to set the title of the pull request which starts with the corresponding JIRA issue number. (e.g. HADOOP-XXXXX. Fix a typo in YYY.) For more details, please see https://cwiki.apache.org/confluence/display/HADOOP/How+To+Contribute -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: common-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: common-issues-h...@hadoop.apache.org
