我在tomcat上运行了一个简单的web应用程序。此web应用程序将文件读写到hdfs。
我面临的问题是每次使用 ./bin/shutdown.sh . 我发现无法加载hadoop shutdownhookmanager异常。
我确信hadoop公用程序（包含shutdownmanager）在tomcat类路径中。
有人能帮我吗？
例外情况：
Oct 14, 2013 5:57:54 PM org.apache.catalina.loader.WebappClassLoader checkThreadLocalMapForLeaks
SEVERE: The web application [] created a ThreadLocal with key of type [com.ebay.kernel.calwrapper.CalTransactionHelper$1] (value [com.ebay.kernel.calwrapper.CalTransactionHelper$1@3d5a1c5f]) and a value of type [com.ebay.kernel.calwrapper.CalTransactionHelper.Stack] (value [[]]) but failed to remove it when the web application was stopped. Threads are going to be renewed over time to try and avoid a probable memory leak.
Oct 14, 2013 5:57:54 PM org.apache.coyote.AbstractProtocol stop
INFO: Stopping ProtocolHandler ["http-bio-8080"]
Oct 14, 2013 5:57:54 PM org.apache.coyote.AbstractProtocol stop
INFO: Stopping ProtocolHandler ["ajp-bio-8009"]
Oct 14, 2013 5:57:54 PM org.apache.coyote.AbstractProtocol destroy
INFO: Destroying ProtocolHandler ["http-bio-8080"]
Oct 14, 2013 5:57:54 PM org.apache.coyote.AbstractProtocol destroy
INFO: Destroying ProtocolHandler ["ajp-bio-8009"]
Oct 14, 2013 5:57:54 PM org.apache.catalina.loader.WebappClassLoader loadClass
INFO: Illegal access: this web application instance has been stopped already. Could not load org.apache.hadoop.util.ShutdownHookManager$2. The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact.
java.lang.IllegalStateException
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1600)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559)
at org.apache.hadoop.util.ShutdownHookManager.getShutdownHooksInOrder(ShutdownHookManager.java:124)
at org.apache.hadoop.util.ShutdownHookManager$1.run(ShutdownHookManager.java:52)
Exception in thread "Thread-9" java.lang.NoClassDefFoundError: org/apache/hadoop/util/ShutdownHookManager$2
at org.apache.hadoop.util.ShutdownHookManager.getShutdownHooksInOrder(ShutdownHookManager.java:124)
at org.apache.hadoop.util.ShutdownHookManager$1.run(ShutdownHookManager.java:52)
Caused by: java.lang.ClassNotFoundException: org.apache.hadoop.util.ShutdownHookManager$2
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1714)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559)
... 2 more
1条答案
按热度按时间2j4z5cfb1#
我也有同样的问题在一个maven魔咒我正在建设。我认为这个问题是由在web应用程序中加载hadoop类的上下文类加载器引起的。这些定义在webappclassloader类中不可见。当jvm关闭发生时，关闭钩子正在执行，这调用了shutdownhookmanager，但是它被加载到了现在已销毁的上下文类加载器中，这就是问题所在。
将hadoopjar放在tomcat的lib目录中可能会有所帮助。或者在启动tomcat时设置一些*\u classpath java选项。这样webappclassloader就会有你的类的定义。
否则，您可以在销毁上下文并忽略上述异常之前手动执行hadoop的shutdown钩子。