docs/troubleshooting/nodetool-nullpointerexception.rst
Problem
^^^^^^^
A NullPointerException is thrown when you run nodetool. For example:
.. code-block:: console
java.lang.NullPointerException at org.apache.cassandra.config.DatabaseDescriptor.getDiskFailurePolicy(DatabaseDescriptor.java:1881) at org.apache.cassandra.utils.JVMStabilityInspector.inspectThrowable(JVMStabilityInspector.java:82) at org.apache.cassandra.io.util.FileUtils.<clinit>(FileUtils.java:79) at org.apache.cassandra.utils.FBUtilities.getToolsOutputDirectory(FBUtilities.java:824) at org.apache.cassandra.tools.NodeTool.printHistory(NodeTool.java:200) at org.apache.cassandra.tools.NodeTool.main(NodeTool.java:168)
Solution ^^^^^^^^ NullPointerException may have more than one cause. When you run the nodetool utility, the exception may indicate an unsupported Java version installed on your machine. Nodetool supports Java 7 and 8.
#. Check your Java version with the java --version command.
#. If nodetool does not support your version, replace it with Java 7 or 8.