I've spent quite a while trying to figure this out. I am working on writing a service which receives a user name and password. It then uses a processor to generate an authentication token which is returned in the Out part of the message. I want to accept JSON formatted parameters, and am trying to get type conversion to work correctly. I've reduced the problem to a self contained unit test which is below:
import org.apache.camel.Exchange;
import org.apache.camel.Processor;
import org.apache.camel.builder.RouteBuilder;
import org.apache.camel.model.dataformat.JsonDataFormat;
import org.apache.camel.model.dataformat.JsonLibrary;
import org.apache.camel.test.junit4.CamelTestSupport;
import org.junit.Test;
import com.thoughtworks.xstream.annotations.XStreamAlias;
public class BasicJsonMarshallingTest extends CamelTestSupport {
@Override
protected RouteBuilder createRouteBuilder() throws Exception {
final Processor simpleProcessor = new Processor() {
@Override public void process(Exchange exchange) throws Exception {
SimpleBean bean = exchange.getIn().getBody(SimpleBean.class);
if(bean == null){
return;
}
exchange.getOut().setBody("a=" + bean.getA() + " b=" + bean.getB());
}
};
return new RouteBuilder() {
@Override public void configure() throws Exception {
JsonDataFormat jsonFormat = new JsonDataFormat(JsonLibrary.XStream);
jsonFormat.setUnmarshalType(SimpleBean.class);
from("direct:service").unmarshal(jsonFormat).process(simpleProcessor);
}
};
}
@Test
public void testSuccessfulAuthentication(){
Exchange lAuthRequest = createExchangeWithBody("{\"simple\":{\"a\":\"v1\",\"b\":\"v2\"}}");
template.send("direct:service", lAuthRequest);
assertEquals("a=v1 b=v2", lAuthRequest.getOut().getBody());
}
@XStreamAlias("simple")
public static final class SimpleBean {
private String a;
private String b;
public void setA(String a) {
this.a = a;
}
public String getA() {
return a;
}
public void setB(String b) {
this.b = b;
}
public String getB() {
return b;
}
}
}
When I run this test, I get this exception in the console:
com.thoughtworks.xstream.mapper.CannotResolveClassException: simple
at com.thoughtworks.xstream.mapper.DefaultMapper.realClass(DefaultMapper.java:56)[xstream-1.4.1.jar:]
at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30)[xstream-1.4.1.jar:]
<snip>
Am I approaching this wrong somehow? Please Help!
I found one way to make this work. I switched to Jackson as my JSON parser and it worked. To do this, all I had to do was change the RouteBuilder to this:
return new RouteBuilder() {
@Override public void configure() throws Exception {
from("direct:service").unmarshal().json(JsonLibrary.Jackson, SimpleBean.class).process(simpleProcessor);
}
};
I also had to change the format of the JSON being sent over the wire from this:
{"simple":{"a":"v1","b":"v2"}}
to this (which I like more anyway):
{"a":"v1", "b":"v2"}