Uploaded image for project: 'Log4j 2'
  1. Log4j 2
  2. LOG4J2-914

ThrowableProxy.getExtendedStackTraceAsString causes NullPointerException

    Details

    • Type: Bug
    • Status: Resolved
    • Priority: Minor
    • Resolution: Fixed
    • Affects Version/s: 2.1
    • Fix Version/s: 2.2
    • Component/s: Core
    • Labels:
      None

      Description

      I'm trying to write a poc with Log4j 2.1, where distributed processes are logging to a remote server. The server is currently running the bundled TcpSocketServer.createSerializedSocketServer with a custom layout plugin.

      A process is logging an exception. I can then see in the custom layout plugin at the log server that the LogEvent doesn't contain a thrown, but that it contains a thrownProxy. So far so good. I'm then trying to get hold of a String representation of the message + stacktrace. I thought that I would be able to e.g invoke ThrowableProxy.getExtendedStackTraceAsString(), but that causes a NullPointerException since the throwable in the ThrowableProxy also is null after deserialization. Looks like ThrowableProxy assumes that throwable isn't null in a few methods.

      The exception that is logged by the client process is a simple new Exception("A message");

      The pom.xml that I'm using:

      <dependency>
      	<groupId>org.apache.logging.log4j</groupId>
      	<artifactId>log4j-api</artifactId>
      	<version>2.1</version>
      </dependency>
      <dependency>
      	<groupId>org.apache.logging.log4j</groupId>
      	<artifactId>log4j-core</artifactId>
      	<version>2.1</version>
      </dependency>
      <dependency>
      	<groupId>com.lmax</groupId>
      	<artifactId>disruptor</artifactId>
      	<version>3.3.0</version>
      </dependency>
      

      The stacktrace that I get in the server:

      2014-12-05 14:30:44,601 ERROR An exception occurred processing Appender XXXXX java.lang.NullPointerException
      	at org.apache.logging.log4j.core.impl.ThrowableProxy.getExtendedStackTraceAsString(ThrowableProxy.java:340)
      	at org.apache.logging.log4j.core.impl.ThrowableProxy.getExtendedStackTraceAsString(ThrowableProxy.java:323)
      

      Workaround:
      To invoke ThrowableProxy. getExtendedStackTrace() and format the stacktrace + message with my own format methods.

        Attachments

          Activity

            People

            • Assignee:
              garydgregory Gary Gregory
              Reporter:
              kajbj Kaj Bjurman
            • Votes:
              0 Vote for this issue
              Watchers:
              3 Start watching this issue

              Dates

              • Created:
                Updated:
                Resolved: