38.6. TypeConverter for CXFPayload

Overview

Apache Camel supports a type converter mechanism, which is used to perform implicit and explicit type conversions of message bodies and message headers. The payload demonstration requires a customer type converter that can convert String objects to CXFPayload objects. This type converter automatically gets invoked at the end of the Camel route, when the generated response message (which is a String type) gets converted into a CXFPayload object.

String to CXFPayload type converter

The String to CXFPayload type converter is implemented in the AdditionalCxfPayloadConverters class, as follows: 
// Java
package com.fusesource.customerwscamelcxfpayload;

import java.io.ByteArrayInputStream;
import java.io.StringWriter;
import java.util.ArrayList;
import java.util.List;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.apache.camel.Converter;
import org.apache.camel.component.cxf.CxfPayload;
import org.apache.cxf.binding.soap.SoapHeader;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;

@Converter
public class AdditionalCxfPayloadConverters {
    ...
    @Converter
    public static CxfPayload<SoapHeader> toCxfPayload(String xml) {
        // System.out.println("To CxfPayload " + xml);
        List<Element> elements = new ArrayList<Element>();
        try {
            Document doc = b.newDocumentBuilder().parse(new ByteArrayInputStream(xml.getBytes()));
            elements.add(doc.getDocumentElement());
        } catch (Exception ex) {
            log.warn("Exception while converting String payload to CxfPayload; resulting payload will be empty.");
        }
        // The CxfPayload is changed to use Source object under layer, the elements API only work if we already setup the list before creating the CxfPayload
        CxfPayload<SoapHeader> ret = new CxfPayload<SoapHeader>(null, elements);
        return ret;
    }
    ...
}

Reference

For full details of the type converter mechanism in Apache Camel, see Section 42.3, “Built-In Type Converters” and Chapter 44, Type Converters.