feat: use lombok @NoArgsConstructor annotation (#645)

* migrate recipe as-is

* Apply suggestions from code review

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

* Minimize implementation

* Add missing AccessLevel imports

* Remove unused import

---------

Co-authored-by: Tim te Beek <timtebeek@gmail.com>
Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: Tim te Beek <tim@moderne.io>

Author: 3 people

src/main/java/org/openrewrite/java/migrate/lombok/UseNoArgsConstructor.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright 2025 the original author or authors.
+ * <p>
+ * Licensed under the Moderne Source Available License (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * <p>
+ * https://docs.moderne.io/licensing/moderne-source-available-license
+ * <p>
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.openrewrite.java.migrate.lombok;
+
+import lombok.AccessLevel;
+import lombok.EqualsAndHashCode;
+import lombok.Value;
+import org.jspecify.annotations.Nullable;
+import org.openrewrite.ExecutionContext;
+import org.openrewrite.Recipe;
+import org.openrewrite.TreeVisitor;
+import org.openrewrite.java.JavaIsoVisitor;
+import org.openrewrite.java.JavaParser;
+import org.openrewrite.java.JavaTemplate;
+import org.openrewrite.java.tree.J;
+import org.openrewrite.java.tree.TypeUtils;
+
+import static java.util.Comparator.comparing;
+
+@Value
+@EqualsAndHashCode(callSuper = false)
+public class UseNoArgsConstructor extends Recipe {
+
+    @Override
+    public String getDisplayName() {
+        //language=markdown
+        return "Use `@NoArgsConstructor` where applicable";
+    }
+
+    @Override
+    public String getDescription() {
+        //language=markdown
+        return "Prefer the Lombok `@NoArgsConstructor` annotation over explicitly written out constructors.";
+    }
+
+    @Override
+    public TreeVisitor<?, ExecutionContext> getVisitor() {
+        return new JavaIsoVisitor<ExecutionContext>() {
+            @Override
+            public J.@Nullable MethodDeclaration visitMethodDeclaration(J.MethodDeclaration method, ExecutionContext ctx) {
+                if (method.isConstructor() &&
+                        method.getParameters().get(0) instanceof J.Empty &&
+                        method.getBody() != null && method.getBody().getStatements().isEmpty()) {
+                    J.ClassDeclaration enclosing = getCursor().firstEnclosing(J.ClassDeclaration.class);
+                    AccessLevel accessLevel = LombokUtils.getAccessLevel(method);
+                    doAfterVisit(new JavaIsoVisitor<ExecutionContext>() {
+                        @Override
+                        public J.ClassDeclaration visitClassDeclaration(J.ClassDeclaration classDecl, ExecutionContext ctx) {
+                            if (TypeUtils.isOfType(classDecl.getType(), enclosing.getType())) {
+                                String template = "@NoArgsConstructor" + (accessLevel == AccessLevel.PUBLIC ?
+                                        "" : "(access = AccessLevel." + accessLevel.name() + ")");
+                                maybeAddImport("lombok.AccessLevel");
+                                maybeAddImport("lombok.NoArgsConstructor");
+                                return JavaTemplate.builder(template)
+                                        .imports("lombok.*")
+                                        .javaParser(JavaParser.fromJavaVersion().classpath("lombok"))
+                                        .build()
+                                        .apply(getCursor(), classDecl.getCoordinates().addAnnotation(comparing(J.Annotation::getSimpleName)));
+                            }
+                            return super.visitClassDeclaration(classDecl, ctx);
+                        }
+                    });
+                    return null;
+                }
+                return super.visitMethodDeclaration(method, ctx);
+            }
+        };
+    }
+}

src/test/java/org/openrewrite/java/migrate/lombok/UseNoArgsConstructorTest.java

@@ -0,0 +1,138 @@
+/*
+ * Copyright 2024 the original author or authors.
+ * <p>
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * <p>
+ * https://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.openrewrite.java.migrate.lombok;
+
+import org.junit.jupiter.api.Test;
+import org.openrewrite.DocumentExample;
+import org.openrewrite.test.RecipeSpec;
+import org.openrewrite.test.RewriteTest;
+
+import static org.openrewrite.java.Assertions.java;
+
+class UseNoArgsConstructorTest implements RewriteTest {
+
+    @Override
+    public void defaults(RecipeSpec spec) {
+        spec.recipe(new UseNoArgsConstructor());
+    }
+
+    @DocumentExample
+    @Test
+    void replaceEmptyPublicConstructor() {
+        rewriteRun(// language=java
+          java(
+            """
+              class A {
+                  public A() {}
+              }
+              """,
+            """
+              import lombok.NoArgsConstructor;
+
+              @NoArgsConstructor
+              class A {
+              }
+              """
+          )
+        );
+    }
+
+    @Test
+    void keepNonEmptyPublicConstructor() {
+        rewriteRun(
+          //language=java
+          java(
+            """
+              class A {
+
+                  int foo;
+
+                  public A() {
+                      foo = 7;
+                  }
+              }
+              """
+          )
+        );
+    }
+
+    @Test
+    void replaceEmptyProtectedConstructor() {
+        rewriteRun(
+          //language=java
+          java(
+            """
+              class A {
+                  protected A() {}
+              }
+              """,
+            """
+              import lombok.AccessLevel;
+              import lombok.NoArgsConstructor;
+
+              @NoArgsConstructor(access = AccessLevel.PROTECTED)
+              class A {
+              }
+              """
+          )
+        );
+    }
+
+    @Test
+    void replaceEmptyPrivateConstructor() {
+        rewriteRun(
+          //language=java
+          java(
+            """
+              class A {
+                  private A() {}
+              }
+              """,
+            """
+              import lombok.AccessLevel;
+              import lombok.NoArgsConstructor;
+
+              @NoArgsConstructor(access = AccessLevel.PRIVATE)
+              class A {
+              }
+              """
+          )
+        );
+    }
+
+    @Test
+    void replaceEmptyPackageConstructor() {
+        rewriteRun(
+          //language=java
+          java(
+            """
+              class A {
+                  A() {}
+              }
+              """,
+            """
+              import lombok.AccessLevel;
+              import lombok.NoArgsConstructor;
+
+              @NoArgsConstructor(access = AccessLevel.PACKAGE)
+              class A {
+              }
+              """
+          )
+        );
+    }
+
+}