[HADOOP-10288] Explicit reference to Log4JLogger breaks non-log4j users

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.3.0
• Fix Version/s: 2.3.0
• Component/s: util
• Hadoop Flags: Reviewed
• Assignee: Todd Lipcon
• Reporter: Todd Lipcon
• Created: 25/Jan/14 19:51
• Updated: 12/Sep/18 11:09
• Resolved: 27/Jan/14 22:15

Description

In HttpRequestLog, we make an explicit reference to the Log4JLogger class for an instanceof check. If the log4j implementation isn't actually on the classpath, the instanceof check throws NoClassDefFoundError instead of returning false. This means that dependent projects that don't use log4j can no longer embed HttpServer – typically this is an issue when they use MiniDFSCluster as part of their testing.

Issue Links

• incorporates: HADOOP-15749 Unhandled Log4JLogger explicit reference breaks non-log4j users