Add an ability to introspect builders

sourcegen-annotations/src/main/java/io/micronaut/sourcegen/annotations/Builder.java

@@ -15,6 +15,9 @@
  */
 package io.micronaut.sourcegen.annotations;
 
+import io.micronaut.core.annotation.Introspected;
+
+import java.lang.annotation.Annotation;
 import java.lang.annotation.Documented;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
@@ -32,4 +35,14 @@
 @Retention(RUNTIME)
 @Target({ElementType.ANNOTATION_TYPE, ElementType.TYPE})
 public @interface Builder {
+
+    /**
+     * Define what annotations should be added to the generated builder. By default,
+     * the builder will have {@link io.micronaut.core.annotation.Introspected} annotation
+     * so that introspection can be created for it.
+     *
+     * @return Array of annotations to apply on the builder
+     */
+    Class<? extends Annotation>[] annotatedWith() default Introspected.class;
+
 }

sourcegen-annotations/src/main/java/io/micronaut/sourcegen/annotations/SuperBuilder.java

@@ -15,6 +15,9 @@
  */
 package io.micronaut.sourcegen.annotations;
 
+import io.micronaut.core.annotation.Introspected;
+
+import java.lang.annotation.Annotation;
 import java.lang.annotation.Documented;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
@@ -33,4 +36,14 @@
 @Retention(RUNTIME)
 @Target({ElementType.ANNOTATION_TYPE, ElementType.TYPE})
 public @interface SuperBuilder {
+
+    /**
+     * Define what annotations should be added to the generated builder. By default,
+     * the builder will have {@link io.micronaut.core.annotation.Introspected} annotation
+     * so that introspection can be created for it.
+     *
+     * @return Array of annotations to apply on the builder
+     */
+    Class<? extends Annotation>[] annotatedWith() default Introspected.class;
+
 }

sourcegen-generator/src/main/java/io/micronaut/sourcegen/generator/visitors/BuilderAnnotationVisitor.java

@@ -15,7 +15,11 @@
  */
 package io.micronaut.sourcegen.generator.visitors;
 
+import io.micronaut.core.annotation.AnnotationClassValue;
+import io.micronaut.core.annotation.AnnotationValue;
+import io.micronaut.core.annotation.Creator;
 import io.micronaut.core.annotation.Internal;
+import io.micronaut.core.annotation.Introspected;
 import io.micronaut.core.annotation.NonNull;
 import io.micronaut.core.annotation.Nullable;
 import io.micronaut.core.bind.annotation.Bindable;
@@ -32,6 +36,7 @@
 import io.micronaut.sourcegen.generator.SourceGenerator;
 import io.micronaut.sourcegen.generator.SourceGenerators;
 import io.micronaut.sourcegen.model.ClassDef;
+import io.micronaut.sourcegen.model.ClassDef.ClassDefBuilder;
 import io.micronaut.sourcegen.model.ClassTypeDef;
 import io.micronaut.sourcegen.model.ExpressionDef;
 import io.micronaut.sourcegen.model.FieldDef;
@@ -41,7 +46,6 @@
 import io.micronaut.sourcegen.model.TypeDef;
 import io.micronaut.sourcegen.model.VariableDef;
 
-import java.lang.annotation.Annotation;
 import java.util.HashSet;
 import java.util.Set;
 import javax.lang.model.element.Modifier;
@@ -71,6 +75,8 @@
 @Internal
 public final class BuilderAnnotationVisitor implements TypeElementVisitor<Builder, Object> {
 
+    public static final String BUILDER_ANNOTATED_WITH_MEMBER = "annotatedWith";
+
     private final Set<String> processed = new HashSet<>();
 
     @Override
@@ -101,6 +107,7 @@ public void visitClass(ClassElement element, VisitorContext context) {
 
             ClassDef.ClassDefBuilder builder = ClassDef.builder(builderClassName)
                 .addModifiers(Modifier.PUBLIC, Modifier.FINAL);
+            addAnnotations(builder, element.getAnnotation(Builder.class));
 
             List<PropertyElement> properties = element.getBeanProperties();
             for (PropertyElement beanProperty : properties) {
@@ -150,8 +157,22 @@ public void visitClass(ClassElement element, VisitorContext context) {
         }
     }
 
-    private MethodDef createAllPropertiesConstructor(ClassTypeDef builderType, List<PropertyElement> properties) {
-        MethodDef.MethodDefBuilder builder = MethodDef.constructor();
+    static void addAnnotations(ClassDefBuilder builder, AnnotationValue<?> annotation) {
+        Optional<AnnotationClassValue[]> annotatedWith = annotation.getConvertibleValues()
+            .get(BUILDER_ANNOTATED_WITH_MEMBER, AnnotationClassValue[].class);
+        if (annotatedWith.isEmpty()) {
+            // Apply the default annotation
+            builder.addAnnotation(Introspected.class);
+        } else {
+            for (AnnotationClassValue<?> value: annotatedWith.get()) {
+                builder.addAnnotation(value.getName());
+            }
+        }
+    }
+
+    static MethodDef createAllPropertiesConstructor(ClassTypeDef builderType, List<PropertyElement> properties) {
+        MethodDef.MethodDefBuilder builder = MethodDef.constructor()
+            .addAnnotation(Creator.class);
         VariableDef.This self = new VariableDef.This(builderType);
         for (PropertyElement parameter : properties) {
             ParameterDef parameterDef = ParameterDef.of(parameter.getName(), TypeDef.of(parameter.getType()));
@@ -180,7 +201,7 @@ private MethodDef createAllPropertiesConstructor(ClassTypeDef builderType, List<
         return builder.build();
     }
 
-    private StatementDef iterableToArrayListStatement(VariableDef.This self, ParameterDef parameterDef) {
+    private static StatementDef iterableToArrayListStatement(VariableDef.This self, ParameterDef parameterDef) {
         return ClassTypeDef.of(ArrayList.class)
             .instantiate()
             .newLocal(parameterDef.getName() + "ArrayList", arrayListVar ->
@@ -198,7 +219,7 @@ private StatementDef iterableToArrayListStatement(VariableDef.This self, Paramet
                             )));
     }
 
-    private StatementDef mapToArrayListStatement(VariableDef.This self, ParameterDef parameterDef) {
+    private static StatementDef mapToArrayListStatement(VariableDef.This self, ParameterDef parameterDef) {
         return self.field(parameterDef.getName(), parameterDef.getType())
             .assign(
                 ClassTypeDef.of(ArrayList.class)

sourcegen-generator/src/main/java/io/micronaut/sourcegen/generator/visitors/SuperBuilderAnnotationVisitor.java

@@ -30,11 +30,12 @@
 import io.micronaut.sourcegen.model.MethodDef;
 import io.micronaut.sourcegen.model.TypeDef;
 
-import java.util.HashSet;
-import java.util.Set;
 import javax.lang.model.element.Modifier;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 
+import static io.micronaut.sourcegen.generator.visitors.BuilderAnnotationVisitor.addAnnotations;
 import static io.micronaut.sourcegen.generator.visitors.BuilderAnnotationVisitor.createModifyPropertyMethod;
 
 /**
@@ -148,6 +149,12 @@ public void visitClass(ClassElement element, VisitorContext context) {
                             )
                         )
                     );
+                addAnnotations(builder, element.getAnnotation(SuperBuilder.class));
+
+                builder.addMethod(MethodDef.constructor().build());
+                if (!properties.isEmpty()) {
+                    builder.addMethod(BuilderAnnotationVisitor.createAllPropertiesConstructor(builderType, properties));
+                }
 
                 builder.addMethod(createSelfMethod());
                 builder.addMethod(BuilderAnnotationVisitor.createBuildMethod(element));

sourcegen-generator/src/test/groovy/io/micronaut/sourcegen/generator/visitors/BuilderAnnotationVisitorSpec.groovy

@@ -10,7 +10,7 @@ class BuilderAnnotationVisitorSpec extends AbstractTypeElementSpec {
         package test;
         import io.micronaut.sourcegen.annotations.Builder;
 
-        @Builder
+        @Builder(annotatedWith = {})
         public record Walrus(
               String name,
               int age,
@@ -35,7 +35,7 @@ class BuilderAnnotationVisitorSpec extends AbstractTypeElementSpec {
         package test;
         import io.micronaut.sourcegen.annotations.Builder;
 
-        @Builder
+        @Builder(annotatedWith = {})
         public record Walrus() {
         }
         """)

test-suite-java/src/test/java/io/micronaut/sourcegen/example/AnimalSuperBuilderTest.java

@@ -16,9 +16,12 @@
 package io.micronaut.sourcegen.example;
 
 import java.lang.reflect.Modifier;
+
+import io.micronaut.core.beans.BeanIntrospection;
 import org.junit.jupiter.api.Test;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
 class AnimalSuperBuilderTest {
@@ -61,6 +64,14 @@ public void testDog() {
     }
 //end::test[]
 
+    @Test
+    public void dogIntrospection() {
+        var introspection = BeanIntrospection.getIntrospection(DogSuperBuilder.class);
+        assertNotNull(introspection);
+        assertEquals(0, introspection.getBeanProperties().size());
+        assertEquals(6, introspection.getConstructorArguments().length);
+    }
+
     @Test
     public void internalTest() {
         assertTrue(Modifier.isPublic(CatSuperBuilder.class.getModifiers()));

test-suite-java/src/test/java/io/micronaut/sourcegen/example/PersonBuilderTest.java

@@ -15,10 +15,12 @@
  */
 package io.micronaut.sourcegen.example;
 
+import io.micronaut.core.beans.BeanIntrospection;
 import org.junit.jupiter.api.Test;
 
 import static org.junit.jupiter.api.Assertions.assertArrayEquals;
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 
 class PersonBuilderTest {
 
@@ -36,6 +38,14 @@ public void buildsPerson() {
     }
 //end::test[]
 
+    @Test
+    public void personIntrospection() {
+        var introspection = BeanIntrospection.getIntrospection(PersonBuilder.class);
+        assertNotNull(introspection);
+        assertEquals(0, introspection.getBeanProperties().size());
+        assertEquals(3, introspection.getConstructorArguments().length);
+    }
+
     @Test
     public void buildsPersonWithPrimitiveDefaults() {
         var person = Person2Builder.builder()