[2/x] Implement joda to java time migration recipe

[amishra-u]

What's changed?

This pr is the second part of implementing the migration from Joda-Time to the Java Time API. It introduces a scanner that analyzes source files to identify variables that are unsafe to migrate.

A variable is considered unsafe if an expression referencing it doesn't have a direct replacement, or if the replacement has not yet been implemented. Any variable connected to an unsafe variable also becomes unsafe.

Key Changes:

• Implemented a scanner that analyzes source files and records unsafe variables, which will later be used by JodaTimeVisitor.
• Added a scanMode to JodaTimeVisitor, which assumes all variables are safe to migrate from Joda-Time to Java-Time. The scanMode flag is exclusively set by JodaTimeScanner.

Not Implemented Yet:

• Support for class variables, method parameters, and other non-local variables.
• A scanning recipe that integrates JodaTimeScanner and JodaTimeVisitor for the migration process.

Checklist

• I've added unit tests to cover both positive and negative cases
• I've read and applied the recipe conventions and best practices
• I've used the IntelliJ IDEA auto-formatter on affected files

[github-actions]

Some suggestions could not be made:

• src/main/java/org/openrewrite/java/migrate/joda/JodaTimeVisitor.java
  • lines 133-135

[sambsnyd]

Most OpenRewrite code uses AtomicBoolean for this purpose.

[timtebeek]

Great to see the progress here! I look forward to the recipes that will use these visitors to make it available for folks to run.

[timtebeek]

Merging this instance already, to clear out open PRs ahead of the release.

[timtebeek]

A quick heads up that we can a recipe in bulk, and will enforce that on PRs in the near future that removed these unused fields:
460fad7

From 460fad7fec51d39bf5e3c02e0fb270946361e95e Mon Sep 17 00:00:00 2001
From: Tim te Beek <timtebeek@gmail.com>
Date: Wed, 23 Oct 2024 19:31:47 +0000
Subject: [PATCH] refactor: Kill your Zombie code

Use this link to re-run the recipe: https://app.moderne.io/builder/mybR2aHWC?organizationId=T3BlblJld3JpdGU%3D

Co-authored-by: Moderne <team@moderne.io>
---
 .../java/migrate/joda/templates/DateTimeFormatTemplates.java    | 2 --
 1 file changed, 2 deletions(-)

diff --git a/src/main/java/org/openrewrite/java/migrate/joda/templates/DateTimeFormatTemplates.java b/src/main/java/org/openrewrite/java/migrate/joda/templates/DateTimeFormatTemplates.java
index 25d5ad37b0..324ea01037 100644
--- a/src/main/java/org/openrewrite/java/migrate/joda/templates/DateTimeFormatTemplates.java
+++ b/src/main/java/org/openrewrite/java/migrate/joda/templates/DateTimeFormatTemplates.java
@@ -25,8 +25,6 @@
 
 public class DateTimeFormatTemplates {
     private final MethodMatcher forPattern = new MethodMatcher(JODA_TIME_FORMAT + " forPattern(String)");
-    private final MethodMatcher forStyle = new MethodMatcher(JODA_TIME_FORMAT + " forStyle(String)");
-    private final MethodMatcher patternForStyle = new MethodMatcher(JODA_TIME_FORMAT + " patternForStyle(String, java.util.Locale)");
     private final MethodMatcher shortDate = new MethodMatcher(JODA_TIME_FORMAT + " shortDate()");
     private final MethodMatcher mediumDate = new MethodMatcher(JODA_TIME_FORMAT + " mediumDate()");
     private final MethodMatcher longDate = new MethodMatcher(JODA_TIME_FORMAT + " longDate()");

Just in case you had planned to use those in the near future still.