Java

Java library API reference

info

In java, you need to decide which JSON implementation you want to use.

Name	Description	License	Status
co.nlighten.json-transform	Java library for transforming JSON objects	Apache License 2.0

Usage

Initialization

• In your app initialization (e.g. main method)

e.g. for Gson as the JSON implementation

import co.nlighten.jsontransform.JsonTransformerConfiguration;
import co.nlighten.jsontransform.adapters.gson.GsonJsonTransformerConfiguration;

JsonTransformerConfiguration.set(
    new GsonJsonTransformerConfiguration(() -> MyGsonBuilder.create())
);

Transformation

• Use the JsonTransformer class to transform JSON objects

Transformer transformer = new JsonTransformer(definition);
var result = transformer.transform(input);

Notice

Result is not unwrapped from the JSON implementation. You can either supply 'true' in the unwrap argument or use the JSON adapter to unwrap it after transformation.

• A way to get the current JSON adapter is

var adapter = JsonTransformerConfiguration.get().getAdapter();

API

JsonTransformer

class JsonTransformer {

    /**
     * Creates a new JSON transformer from definition
     *
     * @param definition       The transformer definition
     * @param adapter          (optional) A specific JSON implementation adapter (otherwise uses the configured default)
     * @param functionsAdapter (optional) A specific transformer functions adapter (otherwise uses the default)                    
     */
    public JsonTransformer(
            final Object definition,
            final JsonAdapter<?, ?, ?> adapter,
            final TransformerFunctionsAdapter functionsAdapter
    );

    /**
     * Transforms the payload using the transformer definition
     *
     * @param payload               The payload to transform
     * @param additionalContext     (optional) Additional context to use in the transformation
     * @param unwrap                (optional) Unwrap the result to POJO from the used JSON implementation (default is false)
     */
    public Object transform(Object payload, Map<String, Object> additionalContext, boolean unwrap);
    
    /**
     * Gets the transformer definition
     */
    public Object getDefinition();
}

JsonTransformerConfiguration

class JsonTransformerConfiguration {

    /**
     * Sets the default configuration (based on a specific JSON implementation)
     * 
     * @param configuration The JSON transformer configuration implementation
     */
    public static void set(JsonTransformerConfiguration configuration);

    /**
     * Gets the current default JSON transformer configuration
     */
    public static JsonTransformerConfiguration get();

    /**
     * Gets the current JSON implementation adapter
     */
    public JsonAdapter<?, ?, ?> getAdapter();
}

JSON Implementations

Possible implementations are:

Name	Notes	JsonTransformerConfiguration class
Gson	package: com.google.code.gson:gson	GsonJsonTransformerConfiguration
Jackson	package: com.fasterxml.jackson.core:jackson-databind	JacksonJsonTransformerConfiguration
JsonOrg	package: org.json:json	JsonOrgJsonTransformerConfiguration
JsonSmart	package: net.minidev:json-smart (v2)	JsonSmartJsonTransformerConfiguration
Pojo	(The default implementation) uses JsonPath's default (embedded) JSON provider	PojoJsonTransformerConfiguration