Third-Party Integrations

/**
 * Enable Jackson ObjectMapper serialization for immutable types.
 * Generates appropriate Jackson annotations (@JsonCreator, @JsonValue)
 * and delegation methods for TokenBuffer-based marshaling.
 */
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.SOURCE)
@interface Jackson.Mapped {}

import org.immutables.value.Value;
import org.immutables.value.Jackson;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.util.Optional;
import java.util.List;

@Value.Immutable
@Jackson.Mapped
public interface User {
  String username();
  String email();
  int age();
  Optional<String> fullName();
  List<String> roles();
}

// Jackson integration usage
ObjectMapper mapper = new ObjectMapper();

User user = ImmutableUser.builder()
    .username("alice")
    .email("alice@example.com")
    .age(30)
    .fullName("Alice Smith")
    .addRoles("user", "admin")
    .build();

// Serialize with Jackson
String json = mapper.writeValueAsString(user);

// Deserialize with Jackson
User restored = mapper.readValue(json, User.class);

// Works with Jackson modules and configurations
mapper.registerModule(new JavaTimeModule());
mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);

/**
 * Generate Gson TypeAdapterFactory for immutable types.
 * Creates efficient type adapters that integrate with Gson's
 * serialization and deserialization system.
 */
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.SOURCE)
@interface Gson.TypeAdapted {}

/**
 * Specify custom Gson field names (similar to @SerializedName).
 * Overrides the default field name used in JSON serialization.
 */
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.SOURCE)
@interface Gson.Named {
  /** Custom field name for Gson serialization */
  String value();
}

/**
 * Specify expected subclasses for Gson polymorphic marshaling.
 * Enables Gson to handle inheritance hierarchies correctly.
 */
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.SOURCE)
@interface Gson.Subclasses {
  /** Subclass types for polymorphic handling */
  Class<?>[] value();
}

import org.immutables.value.Value;
import org.immutables.gson.Gson;
import java.util.List;
import java.util.Map;
import java.time.Instant;

// Basic Gson integration
@Value.Immutable
@Gson.TypeAdapted
public interface Product {
  String name();
  double price();
  List<String> categories();
}

// Custom field names
@Value.Immutable
@Gson.TypeAdapted
public interface ApiRequest {
  @Gson.Named("request_id")
  String requestId();
  
  @Gson.Named("user_data")
  Map<String, Object> userData();
  
  @Gson.Named("created_at")
  Instant createdAt();
}

// Polymorphic types
@Value.Immutable
@Gson.TypeAdapted
@Gson.Subclasses({Circle.class, Rectangle.class})
public interface Shape {
  String type();
  double area();
}

@Value.Immutable
@Gson.TypeAdapted
public interface Circle extends Shape {
  double radius();
  
  @Value.Default
  default String type() { return "circle"; }
  
  @Value.Derived
  default double area() { 
    return Math.PI * radius() * radius(); 
  }
}

// Gson usage
import com.google.gson.GsonBuilder;

GsonBuilder gsonBuilder = new GsonBuilder()
    .registerTypeAdapterFactory(new GsonAdaptersProduct())  // Generated factory
    .registerTypeAdapterFactory(new GsonAdaptersApiRequest())
    .registerTypeAdapterFactory(new GsonAdaptersShape());

com.google.gson.Gson gson = gsonBuilder.create();

Product product = ImmutableProduct.builder()
    .name("Laptop")
    .price(999.99)
    .addCategories("electronics", "computers")
    .build();

String json = gson.toJson(product);
Product restored = gson.fromJson(json, Product.class);

/**
 * Generate MongoDB repository for immutable types.
 * Creates repository classes that integrate with MongoDB driver
 * for CRUD operations on immutable objects.
 */
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.SOURCE)
@interface Mongo.Repository {
  /** 
   * MongoDB collection name. If empty, derives from type name.
   * @return collection name
   */
  String value() default "";
}

/**
 * Mark an attribute as MongoDB _id field.
 * The attribute will be mapped to MongoDB's _id field
 * and handled appropriately during serialization.
 */
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.SOURCE)
@interface Mongo.Id {}

import org.immutables.value.Value;
import org.immutables.value.Mongo;
import com.mongodb.client.MongoDatabase;
import java.time.Instant;
import java.util.List;
import java.util.Optional;

@Value.Immutable
@Mongo.Repository("users")
public interface User {
  @Mongo.Id
  String id();
  
  String username();
  String email();
  Instant createdAt();
  List<String> tags();
  Optional<String> lastLogin();
}

// Generated repository usage
MongoDatabase database = mongoClient.getDatabase("myapp");
UserRepository userRepo = new UserRepository(database);

// Create user
User user = ImmutableUser.builder()
    .id("user123")
    .username("alice")
    .email("alice@example.com")
    .createdAt(Instant.now())
    .addTags("developer", "java")
    .build();

// Repository operations
userRepo.insert(user);
userRepo.save(user);

Optional<User> found = userRepo.findById("user123");
List<User> developers = userRepo.findByTag("developer");

User updated = user.withLastLogin(Instant.now().toString());
userRepo.update(updated);

userRepo.delete("user123");

// Generated repository class
public class UserRepository {
  public UserRepository(MongoDatabase database) { ... }
  
  // Basic CRUD operations
  public void insert(User user) { ... }
  public void save(User user) { ... }
  public Optional<User> findById(String id) { ... }
  public void update(User user) { ... }
  public void delete(String id) { ... }
  
  // Query methods based on attributes
  public List<User> findByUsername(String username) { ... }
  public List<User> findByEmail(String email) { ... }
  public List<User> findByTag(String tag) { ... }
  
  // Aggregation support
  public long count() { ... }
  public List<User> findAll() { ... }
  public List<User> findAll(int skip, int limit) { ... }
}

@Value.Immutable
@Jackson.Mapped
@JsonNaming(PropertyNamingStrategy.SnakeCaseStrategy.class)
@JsonIgnoreProperties(ignoreUnknown = true)
public interface AdvancedJacksonType {
  String firstName();
  String lastName();
  
  @JsonProperty("birth_date")
  LocalDate birthDate();
  
  @JsonIgnore
  String internalField();
}

@Value.Immutable
@Gson.TypeAdapted
public interface AdvancedGsonType {
  @Gson.Named("user_id")
  String userId();
  
  @SerializedName("created_timestamp") 
  long createdTimestamp();
  
  // Gson respects @Expose annotations
  @Expose(serialize = false)
  String secretData();
}

@Value.Immutable
@Mongo.Repository
public interface AdvancedMongoType {
  @Mongo.Id
  ObjectId id();
  
  String name();
  
  @BsonProperty("created_date")
  Date createdDate();
  
  @BsonIgnore
  String computedField();
  
  // Embedded documents
  Address address();
  
  // Collections
  List<Tag> tags();
}

@Value.Immutable
public interface Address {
  String street();
  String city();
  String country();
}

@Value.Immutable
public interface Tag {
  String name();
  String color();
}

<dependency>
  <groupId>com.fasterxml.jackson.core</groupId>
  <artifactId>jackson-core</artifactId>
  <version>2.15.2</version>
</dependency>

<dependency>
  <groupId>com.google.code.gson</groupId>
  <artifactId>gson</artifactId>
  <version>2.10.1</version>
</dependency>

<dependency>
  <groupId>org.mongodb</groupId>
  <artifactId>mongodb-driver-sync</artifactId>
  <version>4.9.1</version>
</dependency>