Camel Velocity Template - access java object properties - apache-camel

Question

I have a camel route which uses Velocity template and in the body I have an object defined as following:
class MailImpl extends AbstractMail{
private BodyContext bodyContext;
public BodyContext getBodyContext() {
return bodyContext;
}
public void setBodyContext(BodyContext bodyContext) {
this.bodyContext = bodyContext;
}
private String test;
public String getTest() {
return test;
}
public void setTest(String test) {
this.test = test;
}
#Override
public String toString() {
return "MailImpl{" +
"bodyContext=" + bodyContext +
'}';
}
}
class BodyContext{
private String value;
public BodyContext(String value) {
this.value = value;
}
public BodyContext() {
}
public String getValue() {
return value;
}
public void setValue(String value) {
this.value = value;
}
#Override
public String toString() {
return "BodyContext{" +
"value='" + value + '\'' +
'}';
}
In the velocity template I would like to access the MailImpl object properties, for example I use ${body.test} and ${body.bodyContext.value} but velocity template does not transform those values (it returns as string ${body.test} and ${body.bodyContext.value}).
One solution could be creating headers for each of of the value I need to use in the template, but as my route is dynamic (I select velocity template based on header) I would like to access the body properties in the velocity context. Is this somehow possible?

Answer 1

You can setup a custom Velocity Context by setting the message header "CamelVelocityContext" (since Camel v2.14). From Camel's test case:
Map<String, Object> variableMap = new HashMap<String, Object>();
Map<String, Object> headersMap = new HashMap<String, Object>();
headersMap.put("name", "Willem");
variableMap.put("headers", headersMap);
variableMap.put("body", "Monday");
variableMap.put("exchange", exchange);
VelocityContext velocityContext = new VelocityContext(variableMap);
exchange.getIn().setHeader(VelocityConstants.VELOCITY_CONTEXT, velocityContext);
exchange.setProperty("item", "7");
With following template:
Dear ${headers.name}. You ordered item ${exchange.properties.item} on ${body}.
You get:
Dear Willem. You ordered item 7 on Monday.