From fa8596036e205beb1bf94d9579b8f11622313e7f Mon Sep 17 00:00:00 2001
From: Jens Knipper <6333850+JensKnipper@users.noreply.github.com>
Date: Fri, 9 Jun 2023 12:54:52 +0200
Subject: [PATCH] #887 add first draft for lombok @Value to java record

---
 .../ConvertLombokValueAnnotationToRecord.java | 81 +++++++++++++++++++
 ...vertLombokValueAnnotationToRecordTest.java | 33 ++++++++
 2 files changed, 114 insertions(+)
 create mode 100644 rewrite-java/src/main/java/org/openrewrite/java/recipes/ConvertLombokValueAnnotationToRecord.java
 create mode 100644 rewrite-java/src/test/java/org/openrewrite/java/recipes/ConvertLombokValueAnnotationToRecordTest.java

diff --git a/rewrite-java/src/main/java/org/openrewrite/java/recipes/ConvertLombokValueAnnotationToRecord.java b/rewrite-java/src/main/java/org/openrewrite/java/recipes/ConvertLombokValueAnnotationToRecord.java
new file mode 100644
index 000000000000..0d3158f76439
--- /dev/null
+++ b/rewrite-java/src/main/java/org/openrewrite/java/recipes/ConvertLombokValueAnnotationToRecord.java
@@ -0,0 +1,81 @@
+package org.openrewrite.java.recipes;
+
+import org.openrewrite.ExecutionContext;
+import org.openrewrite.Recipe;
+import org.openrewrite.TreeVisitor;
+import org.openrewrite.java.JavaIsoVisitor;
+import org.openrewrite.java.tree.J;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class ConvertLombokValueAnnotationToRecord extends Recipe {
+    @Override
+    public String getDisplayName() {
+        return "Convert classes to records where possible";
+    }
+
+    @Override
+    public String getDescription() {
+        return "Convert classes to records where possible.";
+    }
+
+    @Override
+    public TreeVisitor<?, ExecutionContext> getVisitor() {
+        return new ConvertLombokValueAnnotationToRecordVisitor();
+    }
+
+    private class ConvertLombokValueAnnotationToRecordVisitor extends JavaIsoVisitor<ExecutionContext> {
+        /*
+        - lombok @Value to record
+            - delete @Value annotation
+            - but keep all other annotations
+            - delete value import if present
+            - change class to record
+            - define fields as parameter list in record
+            - rename all getters accesses of instances of class
+            - rename all getter methods in class
+            - keep all other methods
+        - ends with Dto or DTO - not relevant, should be included in the others
+        - predefine package and convert all the dtos in there?
+        - all with public fields without getters
+          - change only when final?
+        - private field with getters
+          - no setter
+        - equals, hashcode, toString, getters allowed - when there are other methods, do not convert
+         */
+
+        @Override
+        public J.CompilationUnit visitCompilationUnit(J.CompilationUnit cu, ExecutionContext executionContext) {
+            //System.out.println(TreeVisitingPrinter.printTree(getCursor()));
+
+            List<J.Import> imports = new ArrayList<>(cu.getImports());
+            boolean lombokValueImported = imports.removeIf(it -> it.getTypeName().equals("lombok.Value"));
+
+            List<J.ClassDeclaration> classDeclarations = new ArrayList<>(cu
+                    .getClasses())
+                    .stream()
+                    .map(it -> changeClassDeclaration(it, lombokValueImported, executionContext))
+                    .collect(Collectors.toList());
+
+            J.CompilationUnit newCompilationUnit = cu.withImports(imports).withClasses(classDeclarations);
+            return super.visitCompilationUnit(newCompilationUnit, executionContext);
+        }
+
+        private J.ClassDeclaration changeClassDeclaration(J.ClassDeclaration classDecl, boolean lombokValueImported, ExecutionContext executionContext) {
+
+            List<J.Annotation> annotations = new ArrayList<>(classDecl.getLeadingAnnotations());
+            boolean isValue = annotations
+                    .removeIf(it -> (it.getSimpleName().equals("Value") && lombokValueImported)
+                            || it.getSimpleName().equals("lombok.Value"));
+            if (!isValue) {
+                return super.visitClassDeclaration(classDecl, executionContext);
+            }
+            // TODO only for classes or also for interfaces, enums, annotation?
+
+            J.ClassDeclaration newClassDecl = classDecl.withLeadingAnnotations(annotations).withKind(J.ClassDeclaration.Kind.Type.Record);
+            return super.visitClassDeclaration(newClassDecl, executionContext);
+        }
+    }
+}
diff --git a/rewrite-java/src/test/java/org/openrewrite/java/recipes/ConvertLombokValueAnnotationToRecordTest.java b/rewrite-java/src/test/java/org/openrewrite/java/recipes/ConvertLombokValueAnnotationToRecordTest.java
new file mode 100644
index 000000000000..5d87c9f8e056
--- /dev/null
+++ b/rewrite-java/src/test/java/org/openrewrite/java/recipes/ConvertLombokValueAnnotationToRecordTest.java
@@ -0,0 +1,33 @@
+package org.openrewrite.java.recipes;
+
+import org.junit.jupiter.api.Test;
+import org.openrewrite.test.RewriteTest;
+
+import static org.openrewrite.java.Assertions.java;
+
+public class ConvertLombokValueAnnotationToRecordTest
+        implements RewriteTest {
+    @Test
+    void renameFieldRenamesFoundField() {
+        rewriteRun(
+                recipeSpec -> recipeSpec.recipe(new ConvertLombokValueAnnotationToRecord()),
+                java(
+                        """
+                                package my.test;
+                                       
+                                import lombok.Value;
+                                
+                                @Value
+                                class ValueToRecord {
+                                   String test;
+                                }
+                                """,
+                        """
+                                package my.test;
+                                            
+                                record ValueToRecord(String test) {}
+                                """
+                )
+        );
+    }
+}