I'm working against a very large API, most of whose return values look like:
<{APIMethodName}Resp>
<ResponseCode></ResponseCode>
<ResponseMessage></ResponseMessage>
</{APIMethodName}Resp>
Is there any sort of JAXB fu that will let me do this with just one class? I'm ok if JAXB ignores the root, just throws it away.
Thanks.
You could use the unmarshal method that take a class parameter. This causes the JAXB implementation to ignore the root element.
Related
I defined objects with XSD model and I used Jaxb to create corresponding classes, to be able to load XML files on instance of classes and to generate XML files from instance of classes.
My elements defined on the XSD model are complex with several hierarchical level, using list, ID and IDREF.
One command of my program is to duplicate elements.
I can't use the clone method cause classes of element are generated by JAXB.
So i have tried to do deep copy with BeanUtils.cloneBean, next with SerializationUtils.clone from Apache but both methods don't work correctly with all my objects because of their complexity.
I found a solution that work, using JAXB to create a clone unmarshalling my element :
public ObjectXML duplicate(ObjectXML objectXML) throws JAXBException {
JAXBContext sourceJaxbContext = JAXBContext.newInstance(objectXML.getClass());
JAXBContext targetJaxbContext = JAXBContext.newInstance(objectXML.getClass());
Unmarshaller unmarshaller = targetJaxbContext.createUnmarshaller();
ObjectXML objectCopy = (ObjectXML) unmarshaller.unmarshal(new JAXBSource(sourceJaxbContext, objectXML));
return objectCopy;
}
ObjectXML is my parent class from all elements generated by JAXB. All elements inherit directly or indirectly from this class.
This method work fine except with IDREF attributes that link to another object : JAXB don't know the element that have the corresponding ID when I unmarshall an individual object, so it assign null to the attribute.
Have someone a solution to keep IDREF on the copy when linked object are not supplied to the unmarshal of JAXB?
Thank you for advance.
Few hints.
Try the copyable plugin from JAXB2-Basics. This plugin generates deep reflection-free copying methods which handle JAXB structures very well, and you can also specify your own copying strategy. Disclaimer: I'm the author.
Implement and register your own IDResolver, see this blog post. This would allow you to plug your own ID resolution strategy.
I was wondering whether one can influence the "style" of the code that JAXB generates from XML schema (.xsd) fles. E.g. I would like to:
emit a comment inside newly generated classes, specifically if the class is empty, since that triggers warnings in my environment.
change all setter-methods to return the object instead of "void", so one can do call-chaining like:
X someMethod() {
return new X().setFoo(5).setBar("something");
}
instead of the tedious:
X someMethod() {
X x = new (X);
x.setFoo(5);
x.setBar("something");
return x;
}
Is there some "template" anywhere that JAXB uses and that one could tweak, to achieve such things? Or is that all hard-coded?
M.
There is no template for modifying the generated code easily.
There is, however, a number of plugins. For instance: https://java.net/projects/jaxb2-commons/pages/Fluent-api which is just what you want according to your 2nd bullet.
There are other plugins, e.g. for annotations suppressing warnings - that may help against the 1st bullet.
As an extra, I'd like to mention that not generating Java classes from an XML schema but writing them by hand (plus annotations, of course) is a plausible alternative, provided the XML schema isn't too complex. It may have other advantages besides solving #1 and #2.
I am using SI 4.0 and trying to use object-to-map-transformer as below
<integration:object-to-map-transformer input-channel="inputChannel"
output-channel="outChannel" >
</integration:object-to-map-transformer>
I am sending a object like Person class on the inputChannel. But the moment I fire my test it fails with following error
Caused by: java.lang.IllegalStateException: Neither jackson-databind.jar,
nor jackson-mapper-asl.jar aren't presented in the classpath. at
org.springframework.integration.support.json.JacksonJsonUtils.<clinit>(JacksonJsonUtils.java:41)
I dont understand why it needs jackson. I looked at SI code and can see it needs Jackson class but why is this need - when I simply need to map a simple object to Map?
Thanks
The code to convert object to map looks like:
Map<String,Object> result = this.jsonObjectMapper.fromJson(this.jsonObjectMapper.toJson(payload), Map.class);
Since the out of the box implementation for the JsonObjectMapper is Jackson, it requires that the last one should be presented in the classpath.
We decided to use JSON notation for the Map presentation, since any object in JSON has map-based structure.
If you have another algorithm to do the same, the contribution is welcome!
Or you can simply implement your own Transformer with that logic and use it from generic <transformer>.
I'm working to create some services with JAX-RS, and am relatively new to JAXB (actually XML in general) so please don't assume I know the pre-requisites that I probably should know! Here's the questions: I want to send and receive "partial" objects in XML. That is, imagine one has an object (Java form, obviously) with:
class Thing { int x, String y, Customer z }
I want to be able to send an XML output that contains (dynamically chosen, so I can't use XmlTransient) just x, or just z, or x and y, but not z, or any other combination that suits my client. The point, obviously, is that sometimes the client doesn't need everything, so I can save some bandwidth (particularly with lists of deep, complex objects, which this example clearly doesn't illustrate!).
Also, for input, the same bandwidth argument applies; I would like to be able to have the client send just the particular fields that should be updated in, say, a PUT operation, and ignore the rest, then have the server "merge" those new values onto existing objects and leave the un-mentioned fields unchanged.
This seems to be supported in the Jackson JSON libraries (though I'm still working on it), but I'm having trouble finding it in JAXB. Any ideas?
One thought that I was pondering is whether one can do this in some way via Maps. If I created a Map (potentially nested Maps, for nested coplex objects) of what I want to send, could JAXB send that with a plausible structure? And if it could create such a map on input, I guess I could work through it to make the updates. Not perfect, but maybe?
And yes, I know that the "documents" that will be flying around will probably fail to comply with schemas, having missing fields and all that, but I'm ok with that, provided the infrastructure can be made to work.
Oh, and I know I could do this "manually" with SAX, StAX, or DOM parsing, but I'm hoping there's a rather more automatic way, particularly since JAXB handles the whole objects so effortlessly.
Cheers,
Toby
Note: I'm the EclipseLink JAXB (MOXy) lead and a member of the JAXB (JSR-222) expert group.
EclipseLink JAXB (MOXy) offerst this support through its object graph extension. Object graphs allow you to specify a subset of properties for the purposes of marshalling an unmarshalling. They may be created at runtime programatically:
// Create the Object Graph
ObjectGraph contactInfo = JAXBHelper.getJAXBContext(jc).createObjectGraph(Customer.class);
contactInfo.addAttributeNodes("name");
Subgraph location = contactInfo.addSubgraph("billingAddress");
location.addAttributeNodes("city", "province");
Subgraph simple = contactInfo.addSubgraph("phoneNumbers");
simple.addAttributeNodes("value");
// Output XML - Based on Object Graph
marshaller.setProperty(MarshallerProperties.OBJECT_GRAPH, contactInfo);
marshaller.marshal(customer, System.out);
or statically on the class through annotations:
#XmlNamedObjectGraph(
name="contact info",
attributeNodes={
#XmlNamedAttributeNode("name"),
#XmlNamedAttributeNode(value="billingAddress", subgraph="location"),
#XmlNamedAttributeNode(value="phoneNumbers", subgraph="simple")
},
subgraphs={
#XmlNamedSubgraph(
name="location",
attributeNodes = {
#XmlNamedAttributeNode("city"),
#XmlNamedAttributeNode("province")
}
)
}
)
#XmlRootElement
#XmlAccessorType(XmlAccessType.FIELD)
public class Customer {
For More Information
http://blog.bdoughan.com/2013/03/moxys-object-graphs-partial-models-on.html
http://blog.bdoughan.com/2013/03/moxys-object-graphs-inputoutput-partial.html
http://blog.bdoughan.com/2011/05/specifying-eclipselink-moxy-as-your.html
Basically, I have some models which all use JAXB. However, I have some highly custom functionality to convert to JSON and back so I want to write my own MessageBodyReader/Writer to do the job for me.
Right now, the writing portion is done: if i return one of my models from a REST resource, it goes through my writer. But when I try and accept a model as a FormParam, it doesnt use my MessageBodyReader and instead attempts to unmarshal it using JAXB (which fails).
So how I can tell Jersey to use my Reader instead?
public TestModel testProvider(#FormParam("model") TestModel input){ //doesnt work
return new TestModel(); //this part works!
}
Mark as #Provider
Add the configuration to your web.xml EX:
<init-param><param-name>com.sun.jersey.config.property.packages</param-name> <param-value> your.package.that.contains.the.provider </param-value> </init-param>
Since your writer works, but your reader does not, I'm guessing you have just missed something in your configuration. Some things to check:
Do you have the #Provider annotation on your reader?
Did you correctly implement the isReadable method on your reader?
Do you have the appropriate #Consumes annotation on the reader, does its media type match the media type specified on your service method?