44.3. Accessing Message Content
Accessing message headers
Message headers typically contain the most useful message content from the perspective of a router, because headers are often intended to be processed in a router service. To access header data, you must first get the message from the exchange object (for example, using
Exchange.getIn()), and then use the Message interface to retrieve the individual headers (for example, using Message.getHeader()).
Example 44.4, “Accessing an Authorization Header” shows an example of a custom processor that accesses the value of a header named
Authorization. This example uses the ExchangeHelper.getMandatoryHeader() method, which eliminates the need to test for a null header value.
Example 44.4. Accessing an Authorization Header
import org.apache.camel.*;
import org.apache.camel.util.ExchangeHelper;
public class MyProcessor implements Processor {
public void process(Exchange exchange) {
String auth = ExchangeHelper.getMandatoryHeader(
exchange,
"Authorization",
String.class
);
// process the authorization string...
// ...
}
}
For full details of the
Message interface, see Section 43.2, “Messages”.
Accessing the message body
You can also access the message body. For example, to append a string to the end of the In message, you can use the processor shown in Example 44.5, “Accessing the Message Body”.
Example 44.5. Accessing the Message Body
import org.apache.camel.*;
import org.apache.camel.util.ExchangeHelper;
public class MyProcessor implements Processor {
public void process(Exchange exchange) {
Message in = exchange.getIn();
in.setBody(in.getBody(String.class) + " World!");
}
}Accessing message attachments
You can access a message's attachments using either the
Message.getAttachment() method or the Message.getAttachments() method. See Example 43.2, “Message Interface” for more details.
