io.vertx.codegen.annotations

Annotation Type DataObject

@Retention(value=RUNTIME)
 @Target(value=TYPE)
public @interface DataObject

Declares a data object, such object must provide at least:

• a constructor with JsonObject

When the data object is processed, a model of properties from the setter methods or adder methods. Single valued and multi valued properties are supported.

A setter is just like a JavaBean setter, however the method return type shall be fluent and return the current object. A List setter type declares a multi valued property, otherwise it declares a single valued property.

An adder is a method prefixed by add, its purpose is to declare a List of properties. An adder declares a multi valued property, mapped to the JsonArray type. An adder and a multi valued setter of the same property name are naturally compatible and is encouraged.

Properties types can be:

• any basic type
• a valid data object type
• JsonObject
• JsonArray
• an enum type
• a List of above

A data object can be an interface or an abstract class to accomodate the api design. Data object can extend other data objects.

Sometimes data object can have a toJson() method that takes no arguments and returns a JsonObject representing the data object as a JsonObject.

Vert.x core will generate a json converters using annotation processing to ease conversion, for a given data object, a converter is generated, the name of this converter is the name of the data object with the Converter suffix.

The converter has a fromJson(JsonObject,T) and a toJson(T,JsonObject) public static methods, such methods can be used by the json constructor or the toJson() method to implement the conversion code. By default the generated methods only handle the conversion of the property of the data object and do not handle the properties of the ancestors of this data object, inheritConverter() can be set to true to change this behavior and handle the conversion of the inherited properties as well. The converter generation can be prevented with the generateConverter() annotation member.

Author:

Tim Fox

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
boolean	generateConverter
boolean	inheritConverter
boolean	publicConverter

Element Detail

generateConverter

public abstract boolean generateConverter

Returns:

true if converter should be generated for the data object

Default:

false

inheritConverter

public abstract boolean inheritConverter

Returns:

true if the converter should handle the state of the ancestors.

Default:

false

publicConverter

public abstract boolean publicConverter

Returns:

wether the generated converter should be public or package private

Default:

true