[KYLIN-1963] Delegate the loading of certain package (like slf4j) to tomcat's parent classloader

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: v1.5.4
• Assignee: Hongbin Ma
• Reporter: Hongbin Ma
• Created: 17/Aug/16 07:15
• Updated: 15/Sep/16 03:35
• Resolved: 03/Sep/16 08:56

Description

currently we use hbase command to start tomcat, which then starts kylin as a web application. The default classloader that tomcats assigns to the kylin applications is WebappClassLoader, which will search local repositories before parent classloader.

the design will lead to two separate log4j logging instances in both the "HBase space" and "kylin space", the two loggers will attempt to write to the same file, which is problematic according to official documents