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Samebug tips

  1. ,
    via netty.io by Unknown author

    Needs to add netty-transport-native-epoll with a OS classifier to the classpath, it's not included in netty-all

  2. ,
    Expert tip

    A few things cause this exception:
    1) Check if you have all jars and if they're in the correct path.
    2) Your classpath might be broken, you can define it in the command line with java -cp yourClassPath or at your IDE if you're using one.

Solutions on the web

via JIRA by Jeremy Heminger, 1 year ago
via JIRA by Jeremy Heminger, 2 years ago
java.lang.ClassNotFoundException: java.util.concurrent.ConcurrentMap not found in gnu.gcj.runtime.SystemClassLoader{urls=[file:logstash-1.1.9-monolithic.jar], parent=gnu.gcj.runtime.ExtensionClassLoader{urls=[], parent=null}}	at java.net.URLClassLoader.findClass(libgcj.so.7rh)	at java.lang.ClassLoader.loadClass(libgcj.so.7rh)	at java.lang.ClassLoader.loadClass(libgcj.so.7rh)	at java.lang.Class.initializeClass(libgcj.so.7rh)