Add support to configure adding jackson @JsonPOJOBuilder annotations to generated builders

options.md

@@ -116,3 +116,58 @@ Special handling for collections. See the project test classes for usage.
 | `@RecordBuilder.Options(useUnmodifiableCollections = true/false)`      | Adds special handling for collection record components. The default is `false`.     |
 | `@RecordBuilder.Options(allowNullableCollections = true/false)`        | Adds special null handling for record collectioncomponents. The default is `false`. |
 | `@RecordBuilder.Options(addSingleItemCollectionBuilders = true/false)` | Adds special handling for record collectioncomponents. The default is `false`.      |
+
+## Jackson Support
+
+RecordBuilder can automatically add Jackson annotations to generated builders, supporting both Jackson 2.x and 3.x. Configuration is done via the nested `@JacksonConfig` annotation.
+
+### Basic Example
+
+```java
+@RecordBuilder
+@RecordBuilder.Options(
+    jackson = @RecordBuilder.JacksonConfig(jsonPOJOBuilder = true)
+)
+@JsonDeserialize(builder = UserRecordBuilder.class)
+record UserRecord(String name, int age) {}
+```
+
+### Configuration Options
+
+| option | details |
+|--------|---------|
+| `jackson = @JacksonConfig(...)` | Configures Jackson annotation support for the generated builder. By default, no Jackson annotations are added. |
+
+### JacksonConfig Properties
+
+| property | details |
+|----------|---------|
+| `jsonPOJOBuilder` | **boolean** (default: `false`) - When `true`, adds `@JsonPOJOBuilder` annotation to the generated builder. This annotation works with `@JsonDeserialize(builder = ...)` on the record. |
+| `version` | **JacksonVersion** (default: `AUTO`) - Specifies which Jackson version to use:<br/>• `AUTO` - Automatically detect Jackson version(s) on classpath and add all found annotations. If both Jackson 2.x and 3.x are present, annotations for both versions will be added.<br/>• `JACKSON_2` - Only add Jackson 2.x annotations (`com.fasterxml.jackson.*`). Fails if Jackson 2.x is not found.<br/>• `JACKSON_3` - Only add Jackson 3.x annotations (`tools.jackson.*`). Fails if Jackson 3.x is not found. |
+
+### Examples
+
+#### Auto-detect Jackson version (default)
+```java
+@RecordBuilder.Options(jackson = @RecordBuilder.JacksonConfig(jsonPOJOBuilder = true))
+```
+
+#### Explicit Jackson 2.x
+```java
+@RecordBuilder.Options(
+    jackson = @RecordBuilder.JacksonConfig(
+        jsonPOJOBuilder = true,
+        version = JacksonVersion.JACKSON_2
+    )
+)
+```
+
+#### With custom setter prefix
+```java
+@RecordBuilder.Options(
+    jackson = @RecordBuilder.JacksonConfig(jsonPOJOBuilder = true),
+    setterPrefix = "set"
+)
+```
+
+See [TestJacksonAnnotations](./record-builder-test/src/test/java/io/soabase/recordbuilder/test/TestJacksonAnnotations.java) for complete examples.

pom.xml

@@ -64,6 +64,8 @@
         <hibernate-validator-version>6.2.0.Final</hibernate-validator-version>
         <jakarta-validation-api-version>3.1.0</jakarta-validation-api-version>
         <javax-el-version>3.0.1-b09</javax-el-version>
+        <jackson2-version>2.21.0</jackson2-version>
+        <jackson3-version>3.0.4</jackson3-version>
         <central-publishing-maven-plugin-version>0.7.0</central-publishing-maven-plugin-version>
         <jspecify-version>1.0.0</jspecify-version>
         <lombok-version>1.18.42</lombok-version>
@@ -167,6 +169,17 @@
                 <version>${hibernate-validator-version}</version>
             </dependency>
 
+            <dependency>
+                <groupId>com.fasterxml.jackson.core</groupId>
+                <artifactId>jackson-databind</artifactId>
+                <version>${jackson2-version}</version>
+            </dependency>
+            <dependency>
+                <groupId>tools.jackson.core</groupId>
+                <artifactId>jackson-databind</artifactId>
+                <version>${jackson3-version}</version>
+            </dependency>
+
             <dependency>
                 <groupId>org.glassfish</groupId>
                 <artifactId>javax.el</artifactId>

record-builder-core/src/main/java/io/soabase/recordbuilder/core/RecordBuilder.java

@@ -359,6 +359,31 @@
          * @see #nullablePattern
          */
         boolean defaultNotNull() default false;
+
+        /**
+         * Configuration for Jackson annotation support on generated builders.
+         *
+         * @see JacksonConfig
+         */
+        JacksonConfig jackson() default @JacksonConfig;
+    }
+
+    /**
+     * Configuration for Jackson annotation support on generated builders.
+     */
+    @Retention(RetentionPolicy.CLASS)
+    @Target(ElementType.ANNOTATION_TYPE)
+    @interface JacksonConfig {
+        /**
+         * Add {@code @JsonPOJOBuilder} annotation to generated builder. This annotation works with
+         * {@code @JsonDeserialize(builder = ...)} on the record.
+         */
+        boolean jsonPOJOBuilder() default false;
+
+        /**
+         * Which Jackson version to use for annotations.
+         */
+        JacksonVersion version() default JacksonVersion.AUTO;
     }
 
     @Retention(RetentionPolicy.CLASS)
@@ -378,6 +403,29 @@ enum ConcreteSettersForOptionalMode {
         DISABLED, ENABLED, ENABLED_WITH_NULLABLE_ANNOTATION,
     }
 
+    /**
+     * Specifies which Jackson version(s) to use when generating builder annotations.
+     */
+    enum JacksonVersion {
+        /**
+         * Automatically detect Jackson version(s) on classpath and add all found annotations. If both Jackson 2.x and
+         * 3.x are present, both annotations will be added.
+         */
+        AUTO,
+
+        /**
+         * Only add Jackson 2.x annotations (com.fasterxml.jackson.databind.annotation.JsonPOJOBuilder). Fails if
+         * Jackson 2.x is not found on classpath.
+         */
+        JACKSON_2,
+
+        /**
+         * Only add Jackson 3.x annotations (tools.jackson.databind.annotation.JsonPOJOBuilder). Fails if Jackson 3.x is
+         * not found on classpath.
+         */
+        JACKSON_3,
+    }
+
     /**
      * Apply to record components to specify a field initializer for the generated builder
      */

record-builder-processor/src/main/java/io/soabase/recordbuilder/processor/InternalRecordBuilderProcessor.java

@@ -89,6 +89,8 @@ class InternalRecordBuilderProcessor {
             builder.addAnnotation(recordBuilderGeneratedAnnotation);
         }
 
+        new JacksonSupport(processingEnv).addJacksonAnnotations(metaData, builder);
+
         if (!validateMethodNameConflicts(processingEnv, recordFacade.element())) {
             builderType = Optional.empty();
             return;

record-builder-processor/src/main/java/io/soabase/recordbuilder/processor/JacksonSupport.java

@@ -0,0 +1,112 @@
+/*
+ * Copyright 2019 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
+ *
+ * http://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 io.soabase.recordbuilder.processor;
+
+import com.palantir.javapoet.AnnotationSpec;
+import com.palantir.javapoet.ClassName;
+import com.palantir.javapoet.TypeSpec;
+import io.soabase.recordbuilder.core.RecordBuilder;
+
+import javax.annotation.processing.ProcessingEnvironment;
+
+import static javax.tools.Diagnostic.Kind.ERROR;
+
+class JacksonSupport {
+    private static final String JACKSON_2_ANNOTATION_PACKAGE = "com.fasterxml.jackson.databind.annotation";
+    private static final String JACKSON_3_ANNOTATION_PACKAGE = "tools.jackson.databind.annotation";
+
+    private static final String JSON_POJO_BUILDER = "JsonPOJOBuilder";
+
+    private final ProcessingEnvironment processingEnv;
+    private final boolean jackson2Present;
+    private final boolean jackson3Present;
+
+    JacksonSupport(ProcessingEnvironment processingEnv) {
+        this.processingEnv = processingEnv;
+        jackson2Present = isAnnotationClassPresent(JACKSON_2_ANNOTATION_PACKAGE, JSON_POJO_BUILDER);
+        jackson3Present = isAnnotationClassPresent(JACKSON_3_ANNOTATION_PACKAGE, JSON_POJO_BUILDER);
+    }
+
+    private boolean isAnnotationClassPresent(String packageName, String className) {
+        return processingEnv.getElementUtils().getTypeElement(packageName + "." + className) != null;
+    }
+
+    public void addJacksonAnnotations(RecordBuilder.Options metaData, TypeSpec.Builder builder) {
+        // return without further processing if no annotation is enabled
+        if (!anyJacksonAnnotationEnabled(metaData)) {
+            return;
+        }
+
+        switch (metaData.jackson().version()) {
+        case AUTO -> {
+            if (!jackson2Present && !jackson3Present) {
+                processingEnv.getMessager().printMessage(ERROR,
+                        "jackson.jsonPOJOBuilder is enabled but Jackson is not found on classpath. "
+                                + "Add jackson-databind dependency or disable jsonPOJOBuilder.");
+                return;
+            }
+
+            if (jackson2Present) {
+                addJacksonAnnotations(metaData, builder, JACKSON_2_ANNOTATION_PACKAGE);
+            }
+
+            if (jackson3Present) {
+                addJacksonAnnotations(metaData, builder, JACKSON_3_ANNOTATION_PACKAGE);
+            }
+        }
+
+        case JACKSON_2 -> {
+            if (!jackson2Present) {
+                processingEnv.getMessager().printMessage(ERROR,
+                        "jackson.version is set to JACKSON_2 but Jackson 2.x is not found on classpath. "
+                                + "Add jackson-databind 2.x dependency or change version to AUTO.");
+                return;
+            }
+
+            addJacksonAnnotations(metaData, builder, JACKSON_2_ANNOTATION_PACKAGE);
+        }
+
+        case JACKSON_3 -> {
+            if (!jackson3Present) {
+                processingEnv.getMessager().printMessage(ERROR,
+                        "jackson.version is set to JACKSON_3 but Jackson 3.x is not found on classpath. "
+                                + "Add jackson-databind 3.x dependency or change version to AUTO.");
+                return;
+            }
+
+            addJacksonAnnotations(metaData, builder, JACKSON_3_ANNOTATION_PACKAGE);
+        }
+        }
+    }
+
+    private boolean anyJacksonAnnotationEnabled(RecordBuilder.Options metaData) {
+        return metaData.jackson().jsonPOJOBuilder();
+    }
+
+    private void addJacksonAnnotations(RecordBuilder.Options metaData, TypeSpec.Builder builder, String packageName) {
+        if (metaData.jackson().jsonPOJOBuilder()) {
+            addJsonPOJOBuilderAnnotation(metaData, builder, packageName);
+        }
+    }
+
+    private void addJsonPOJOBuilderAnnotation(RecordBuilder.Options metaData, TypeSpec.Builder builder,
+            String packageName) {
+        final var annotationSpec = AnnotationSpec.builder(ClassName.get(packageName, JSON_POJO_BUILDER))
+                .addMember("withPrefix", "$S", metaData.setterPrefix()).build();
+
+        builder.addAnnotation(annotationSpec);
+    }
+}

record-builder-test/pom.xml

@@ -72,6 +72,15 @@
             <scope>provided</scope>
         </dependency>
 
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>tools.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+        </dependency>
+
         <dependency>
             <groupId>org.glassfish</groupId>
             <artifactId>javax.el</artifactId>

record-builder-test/src/main/java/io/soabase/recordbuilder/test/JacksonAnnotated.java

@@ -0,0 +1,67 @@
+/*
+ * Copyright 2019 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
+ *
+ * http://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 io.soabase.recordbuilder.test;
+
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+import io.soabase.recordbuilder.core.RecordBuilder;
+
+import java.util.Map;
+
+public interface JacksonAnnotated {
+    String name();
+
+    String type();
+
+    Map<String, Object> properties();
+
+    @RecordBuilder
+    @RecordBuilder.Options(jackson = @RecordBuilder.JacksonConfig(jsonPOJOBuilder = true), useImmutableCollections = true, prefixEnclosingClassNames = false)
+    @JsonDeserialize(builder = JacksonAnnotatedRecordBuilder.class)
+    record JacksonAnnotatedRecord(String name, @RecordBuilder.Initializer("DEFAULT_TYPE") String type,
+            Map<String, Object> properties) implements JacksonAnnotated {
+        public static final String DEFAULT_TYPE = "dummy";
+    }
+
+    @RecordBuilder
+    @RecordBuilder.Options(jackson = @RecordBuilder.JacksonConfig(jsonPOJOBuilder = true), useImmutableCollections = true, prefixEnclosingClassNames = false, setterPrefix = "set")
+    @JsonDeserialize(builder = JacksonAnnotatedRecordCustomSetterPrefixBuilder.class)
+    record JacksonAnnotatedRecordCustomSetterPrefix(String name, @RecordBuilder.Initializer("DEFAULT_TYPE") String type,
+            Map<String, Object> properties) implements JacksonAnnotated {
+        public static final String DEFAULT_TYPE = "dummy";
+    }
+
+    @RecordBuilder
+    @RecordBuilder.Options(jackson = @RecordBuilder.JacksonConfig(jsonPOJOBuilder = true, version = RecordBuilder.JacksonVersion.JACKSON_2), useImmutableCollections = true, prefixEnclosingClassNames = false)
+    @JsonDeserialize(builder = JacksonAnnotatedRecordJackson2Builder.class)
+    record JacksonAnnotatedRecordJackson2(String name, @RecordBuilder.Initializer("DEFAULT_TYPE") String type,
+            Map<String, Object> properties) implements JacksonAnnotated {
+        public static final String DEFAULT_TYPE = "dummy";
+    }
+
+    @RecordBuilder
+    @RecordBuilder.Options(jackson = @RecordBuilder.JacksonConfig(jsonPOJOBuilder = true, version = RecordBuilder.JacksonVersion.JACKSON_3), useImmutableCollections = true, prefixEnclosingClassNames = false)
+    @tools.jackson.databind.annotation.JsonDeserialize(builder = JacksonAnnotatedRecordJackson3Builder.class)
+    record JacksonAnnotatedRecordJackson3(String name, @RecordBuilder.Initializer("DEFAULT_TYPE") String type,
+            Map<String, Object> properties) implements JacksonAnnotated {
+        public static final String DEFAULT_TYPE = "dummy";
+    }
+
+    @RecordBuilder
+    @RecordBuilder.Options(prefixEnclosingClassNames = false)
+    record JacksonAnnotatedRecordNoJackson(String name, String type, Map<String, Object> properties)
+            implements JacksonAnnotated {
+    }
+}