[HDFS-16616] Remove the use if Sets#newHashSet and Sets#newTreeSet

• Type: Task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.4.0
• Fix Version/s: 3.4.0
• Component/s: hdfs-common
• Labels: pull-request-available
• Target Version/s: 3.4.0
• Hadoop Flags: Reviewed
• Assignee: Samrat Deb
• Reporter: Samrat Deb
• Created: 03/Jun/22 21:49
• Updated: 12/Feb/24 07:42
• Resolved: 22/Jun/22 04:48

Description

As part of removing guava dependencies  HADOOP-17115, HADOOP-17721, HADOOP-17722 and HADOOP-17720 are fixed,

Currently the code call util function to create HashSet and TreeSet in the repo . These function calls dont have much importance as it is calling internally new HashSet<> / new TreeSet<> from java.utils 

This task is to clean up all the function calls to create sets which is redundant 

Before moving to java8 , sets were created using guava functions and API , now since this is moved away and util code in the hadoop now looks like

1. 
public static <E extends Comparable> TreeSet<E> newTreeSet() { return new TreeSet<E>();

2. 
public static <E> HashSet<E> newHashSet()

{ return new HashSet(); }

These interfaces dont do anything much just a extra layer of function call 

please refer to the task 
https://issues.apache.org/jira/browse/HADOOP-17726

Can anyone review if this ticket add some value in the code. 
Looking forward to some input/ thoughts . If not adding any value we can close it and not move forward with changes !

Issue Links

• is related to: HADOOP-18265 replace with HashSet/TreeSet constructor directly in hadoop-hdfs-project
• links to: GitHub Pull Request #4400