[HADOOP-10625] Configuration: names should be trimmed when putting/getting to properties

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.4.0
• Fix Version/s: 2.5.0
• Component/s: conf
• Assignee: Wangda Tan
• Reporter: Wangda Tan
• Created: 22/May/14 05:18
• Updated: 15/Aug/14 05:39
• Resolved: 28/May/14 17:12

Description

Currently, Hadoop will not trim name when putting a pair of k/v to property. But when loading configuration from file, names will be trimmed:
(In Configuration.java)

          if ("name".equals(field.getTagName()) && field.hasChildNodes())
            attr = StringInterner.weakIntern(
                ((Text)field.getFirstChild()).getData().trim());
          if ("value".equals(field.getTagName()) && field.hasChildNodes())
            value = StringInterner.weakIntern(
                ((Text)field.getFirstChild()).getData());

With this behavior, following steps will be problematic:
1. User incorrectly set " hadoop.key=value" (with a space before hadoop.key)
2. User try to get "hadoop.key", cannot get "value"
3. Serialize/deserialize configuration (Like what did in MR)
4. User try to get "hadoop.key", can get "value", which will make inconsistency problem.