Camel Components

JSON JSON-B

Since Camel 3.7

JSON-B is a Data Format that uses the standard (javax) JSON-B library.

  • Java

  • XML

  • YAML

from("activemq:My.Queue")
    .marshal().json(JsonLibrary.Jsonb)
    .to("mqseries:Another.Queue");
<route>
  <from uri="activemq:My.Queue"/>
  <marshal><json library="Jsonb"/></marshal>
  <to uri="mqseries:Another.Queue"/>
</route>
- route:
    from:
      uri: activemq:My.Queue
      steps:
        - marshal:
            json:
              library: Jsonb
        - to:
            uri: mqseries:Another.Queue

JSON-B Options

The JSON JSON-B dataformat supports the following options which are listed below.

Name Default Java Type Description

objectMapper (common)

String

Lookup and use the existing Jsonb instance with the given id.

prettyPrint (common)

false

Boolean

To enable pretty printing output nicely formatted. Is by default false.

unmarshalType (common)

String

Class name of the java type to use when unmarshalling.

allowUnmarshallType (common)

false

Boolean

If enabled then Jackson, Gson or JSON-B is allowed to attempt to use the CamelJacksonUnmarshalType, CamelGsonUnmarshalType or CamelJsonbUnmarshallType header during the unmarshalling. This should only be enabled when desired to be used.

Message Body

The message body at each side of the JSON JSON-B data format: Marshal input and Unmarshal input are the bodies marshal and unmarshal can take, and Marshal output and Unmarshal output the body after them.

Side Body Description

Marshal input

any

A Map, a List or a POJO to write as JSON. Bytes, a stream, a file from a file consumer, or a String with a JSON object or array is written as it is; any other String becomes a JSON string.

Marshal output

stream, as json

The JSON in the stream cache, or a byte array when stream caching is off.

Unmarshal input

text, bytes, stream or file, as json

Unmarshal output

map or list

A Map (HashMap with Yasson) for a JSON object, a List (ArrayList) for an array, with the numbers as BigDecimal; an object of the class unmarshalType names.

Not known when unmarshalType or allowUnmarshallType is set.

The bodies are the ones with the default options. A side that is not listed is not known, and tooling does not guess it. The carriers are described in the Camel Catalog.

A body that is already JSON

A body that already is the JSON text is written as it is, not serialized as a Java object: a file from a consumer such as file or ftp, an InputStream, a byte[], and a String whose text is a JSON object or array (it starts with { and ends with }, or [ and ]). So marshal: json after reading a JSON file, or after building the JSON with a template or a Simple expression, sends that JSON unchanged. Any other String is written as a JSON string, and POJOs, maps and lists are marshalled as usual. The Jackson, Gson, Jsonb and Fastjson JSON data formats do the same.

Dependencies

To use JSON-B in your Camel routes, you need to add the dependency on camel-jsonb that implements this data format.

If you use Maven, you could add the following to your pom.xml, substituting the version number for the latest & greatest release.

<dependency>
  <groupId>org.apache.camel</groupId>
  <artifactId>camel-jsonb</artifactId>
  <version>x.x.x</version>
  <!-- use the same version as your Camel core version -->
</dependency>

You have to add a dependency on the implementation of a jsonb specification.

If you want to add the Johnzon implementation, and you are using maven, add following to your pom.xml:

<dependency>
  <groupId>org.apache.johnzon</groupId>
  <artifactId>johnzon-jsonb</artifactId>
  <version>x.x.x</version>
</dependency>