[SOLR-8454] Improve logging by ZkStateReader and clean up dead code

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 5.5, 6.0
• Component/s: SolrCloud
• Assignee: Shai Erera
• Reporter: Shai Erera
• Created: 22/Dec/15 07:34
• Updated: 09/May/16 18:46
• Resolved: 22/Dec/15 13:39

Description

Improve logging output by ZkStateReader, by adding the following:

• Use LOG.foo() with parameters properly (i.e. not concatenating strings w/ +)
• Surround parameters with [], to help readability, especially w/ empty values
• Add missing string messages, where I felt a message will clarify
• Convert some try-catch to a try-multicatch and improve output log message

Also, clean up dead code.