What data transformation options does Camel provide (Type Converters, Data Formats, Transformers)?

Apache Camel provides three complementary layers for data transformation:

• Type Converters: Implicit, automatic conversions between Java types (e.g., byte[] to String, File to InputStream). Applied transparently when you call getBody(TargetClass.class). Registered via @Converter annotations or explicit TypeConverterRegistry.
• Data Formats: Marshal (Java object —> bytes/String) and unmarshal (bytes/String —> Java object) operations. Used explicitly in routes with .marshal() and .unmarshal(). Formats include JSON (Jackson), XML (JAXB), CSV, Avro, Protobuf, EDI, HL7.
• Transformers: Route-level pipeline steps that use a processor, bean, or expression to reshape the body. This includes .transform(expression), .setBody(), .enrich(), and custom Processors.

// Type converter (implicit, no code needed in route):
String body = exchange.getIn().getBody(String.class); // auto-converts byte[]

// Data format: JSON marshal/unmarshal
from("direct:in")
    .unmarshal().json(Order.class)   // JSON bytes -> Order POJO
    .process(new OrderProcessor())
    .marshal().json()               // Order POJO -> JSON bytes
    .to("direct:out");

// Transformer using expression:
from("direct:transform")
    .transform(simple("${body.toUpperCase()}"));

Type Converters are always implicit — they run without any route configuration. Data Formats require explicit marshal()/unmarshal() calls and add the conversion to the pipeline. Transformers are explicit processing steps. Choosing between them: if you need structural format change (JSON to XML), use Data Formats; if you need business-level object manipulation, use Processors or Beans; implicit type coercion uses converters.