Configure Java version for Oozie

Oozie runs multiple Java Virtual Machine (JVM) processes. This page explains how to configure the Java version for each process.

• Oozie Server: Set JAVA_HOME in the oozie-env classification to update the Java version for the EmbeddedOozieServer.

• Oozie Launcher AM: Oozie Launcher AM is a single-mapper MR job that invokes the appropriate application client libraries such as Hadoop and Hive. Unless otherwise configured, the runtime versions for Oozie Launcher AM are the same as the Java runtimes for Hadoop in the EMR cluster. To configure the Java runtime for Oozie Launcher AM, set the following property in the workflow.xml for the job:

  <property>
       <name>mapred.child.env</name>
       <value>JAVA_HOME=/path/to/JAVA_HOME</value>
   </property>

  This property ensures that the Oozie Launcher AM for the Oozie job runs on the Java version that you specify, rather than the Java version that is set in Hadoop.

• Application Client Executable: Because Oozie Launcher AM invokes the application client by default, the Java runtime for the client executable is the same as the Oozie Launcher AM.

• Applications launched by an Oozie job: Unless otherwise specified, the runtime versions for the actual application JVMs that are launched by an Oozie job are the same as the Java runtimes for Hadoop in the EMR cluster. Depending on the type of Oozie Workflow Action used to launch the application in an Oozie job (Spark or Hive action), you can update the default Java runtime for the actual application JVMs in the workflow.xml for the Oozie job.