Parent issue: #19604

Description

Add Checkstyle checks for all rules under §3.12 - Lambda Expressions of the OpenJDK Java Style Guidelines v6.

Rules Covered

From §3.12 - Lambda Expressions:

1. Expression lambdas are preferred over single-line block lambdas. - MatchXpath Check
2. The parameter types should be omitted unless they improve readability. - MatchXpath Check
3. If a lambda expression stretches over more than a few lines, consider creating a method. - LambdaBodyLengthCheck Check
4. Method references should generally be preferred over lambda expressions. - Not coverable
   by Checkstyle

Checks to add to openjdk_checks.xml

TreeWalker-level

<module name="TreeWalker">
  <module name="MatchXpath"><!-- expression lambda over block lambda --></ module>
  <module name="MatchXpath"><!-- omit parameter types --></ module>
  <module name="LambdaBodyLengthCheck"/>
</module>

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