Parent issue: #19604 #19798

Description

Add Checkstyle checks for all rules under §3.10 - Variable Declarations of the OpenJDK Java Style Guidelines v6.

Rules Covered

From §3.10 - Variable Declarations:

1. One variable per declaration (and at most one declaration per line) - MultipleVariableDeclarations Check
2. Square brackets of arrays should be at the type (String[] args) and not on the variable (String args[]). - ArrayTypeStyle Check with javaStyle set to true (default)
3. Declare a local variable right before it is first used, and initialize it as close to the declaration as possible. - VariableDeclarationUsageDistance Check

Checks to add to openjdk_checks.xml

TreeWalker-level

<module name="TreeWalker">
  <module name="MultipleVariableDeclarations"/>
  <module name="ArrayTypeStyle"/>
  <module name="VariableDeclarationUsageDistance"/>
</module>

Progress Tracker