Introduce support to create domain objects via factory methods.

Issue #2476.

src/main/java/org/springframework/data/annotation/EntityCreatorAnnotation.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2011-2021 the original author or authors.
+ *
+ * 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
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * 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.springframework.data.annotation;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Marker annotation to declare a constructor or factory method annotation as factory/preferred constructor annotation.
+ *
+ * @author Mark Paluch
+ * @since 3.0
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Target({ ElementType.ANNOTATION_TYPE })
+public @interface EntityCreatorAnnotation {
+}

src/main/java/org/springframework/data/annotation/FactoryMethod.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2011-2021 the original author or authors.
+ *
+ * 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
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * 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.springframework.data.annotation;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Annotation to declare a {@code static} method as factory method for class instantiation.
+ *
+ * @author Mark Paluch
+ * @since 3.0
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Target({ ElementType.METHOD, ElementType.ANNOTATION_TYPE })
+@EntityCreatorAnnotation
+public @interface FactoryMethod {
+}

src/main/java/org/springframework/data/annotation/PersistenceConstructor.java

@@ -21,9 +21,13 @@ import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
 /**
+ * Annotation to declare a constructor for instantiation.
+ *
  * @author Jon Brisbin
+ * @author Mark Paluch
  */
 @Retention(RetentionPolicy.RUNTIME)
-@Target(ElementType.CONSTRUCTOR)
+@Target({ ElementType.CONSTRUCTOR, ElementType.ANNOTATION_TYPE })
+@EntityCreatorAnnotation
 public @interface PersistenceConstructor {
 }