Sangjin Lee created HADOOP-12773: ------------------------------------ Summary: HBase classes fail to load with client/job classloader enabled Key: HADOOP-12773 URL: https://issues.apache.org/jira/browse/HADOOP-12773 Project: Hadoop Common Issue Type: Bug Components: util Affects Versions: 2.6.3 Reporter: Sangjin Lee Assignee: Sangjin Lee
Currently if a user uses HBase and enables the client/job classloader, the job fails to load HBase classes. For example, {noformat} java.lang.NoClassDefFoundError: Lorg/apache/hadoop/hbase/client/HBaseAdmin; at java.lang.Class.getDeclaredFields0(Native Method) at java.lang.Class.privateGetDeclaredFields(Class.java:2509) at java.lang.Class.getDeclaredField(Class.java:1959) at java.io.ObjectStreamClass.getDeclaredSUID(ObjectStreamClass.java:1703) at java.io.ObjectStreamClass.access$700(ObjectStreamClass.java:72) at java.io.ObjectStreamClass$2.run(ObjectStreamClass.java:484) at java.io.ObjectStreamClass$2.run(ObjectStreamClass.java:472) at java.security.AccessController.doPrivileged(Native Method) at java.io.ObjectStreamClass.<init>(ObjectStreamClass.java:472) at java.io.ObjectStreamClass.lookup(ObjectStreamClass.java:369) {noformat} It is because the HBase classes (org.apache.hadoop.hbase.\*) meet the system classes criteria which are supposed to be loaded strictly from the base classloader. But hadoop does not provide HBase as a dependency. We should exclude the HBase classes from the system classes until/unless HBase is provided by a future version of hadoop. -- This message was sent by Atlassian JIRA (v6.3.4#6332)