Jackson

EasyApi supports Jackson serialization annotations for accurate JSON representation.

Supported Annotations

Annotation	Description
@JsonProperty	Specifies the JSON property name and index for ordering
@JsonIgnore	Excludes a field from JSON serialization
@JsonIgnoreProperties	Excludes multiple fields from JSON serialization (class-level and nested)
@JsonInclude	Controls when a field is included in JSON
@JsonFormat	Specifies the format for date/time fields
@JsonAlias	Defines alternative names for a property
@JsonNaming	Defines a naming strategy for properties
@JsonView	Controls which fields are included in a view
@JsonTypeInfo / @JsonSubTypes	Handles polymorphic types
@JsonPropertyOrder	Specifies the order of properties in JSON output
@JsonUnwrapped	Flattens a nested object's properties into the parent, with optional prefix/suffix

Example

public class User {

    @JsonProperty("user_name")
    private String name;

    @JsonIgnore
    private String password;

    @JsonInclude(JsonInclude.Include.NON_NULL)
    private String email;

    @JsonFormat(pattern = "yyyy-MM-dd")
    private Date birthday;
}

@JsonPropertyOrder Support

EasyApi respects @JsonPropertyOrder to control field ordering in the output:

@JsonPropertyOrder({"name", "email", "id"})
public class UserDTO {
    private Long id;        // Will appear 3rd
    private String name;    // Will appear 1st
    private String email;   // Will appear 2nd
}

When alphabetic = true is set, fields not listed in the annotation will be sorted alphabetically:

@JsonPropertyOrder(value = {"name"}, alphabetic = true)
public class UserDTO {
    private Long id;        // Will appear after "name", sorted alphabetically
    private String name;    // Will appear 1st
    private String email;   // Will appear after "name", sorted alphabetically
}

The @JsonProperty(index) annotation is also supported for individual field ordering.

@JsonIgnoreProperties Support

EasyApi respects @JsonIgnoreProperties on both classes and nested fields:

@JsonIgnoreProperties({"internalId", "metadata"})
public class UserDTO {
    private Long internalId;  // Will be ignored
    private String name;      // Will be included
    private String metadata;  // Will be ignored
}

Nested @JsonIgnoreProperties on fields is also supported — when a field's type has @JsonIgnoreProperties, those properties will be excluded from the nested object in the output.

@JsonUnwrapped Support

EasyApi handles @JsonUnwrapped by flattening the nested object's properties into the parent. It also supports the prefix and suffix attributes:

public class User {
    private String name;

    @JsonUnwrapped(prefix = "address_")
    private Address address;
}

public class Address {
    private String street;
    private String city;
}

The resulting JSON will be:

{
    "name": "John",
    "address_street": "123 Main St",
    "address_city": "Springfield"
}

@JsonView Support

EasyApi respects @JsonView annotations to control which fields appear in the API response. Fields are included only if their @JsonView matches the view specified on the API method:

public class User {
    @JsonView(Views.Public.class)
    private String name;

    @JsonView(Views.Internal.class)
    private String email;
}

@RestController
public class UserController {
    @JsonView(Views.Public.class)
    @GetMapping("/users/{id}")
    public User getUser(@PathVariable Long id) {
        // Only "name" will appear in the response
    }
}

JSON Rule Configuration

You can customize JSON serialization behavior using rules:

# Ignore specific fields by name
json.rule.field.ignore=#regex:password|secret|token

# Rename fields
json.rule.field.name=#regex:^(.)=$1

# Convert types
json.rule.convert[#regex:com.example.Wrapper<(.*?)>]=${1}

See JSON Rules for the full list of available rules.