I'm trying to inject JAXB annotation at runtime using Javassist. I have written following code:

public class AssistAnnotationInjector { 
   public static void addAnnotationRunTime(String className, String fieldName) throws NotFoundException, CannotCompileException, IOException, ClassNotFoundException{
  CtClass ctClass = ClassPool.getDefault().get(className);
 ClassFile ccFile = ctClass.getClassFile(); 
ConstPool constPool = ccFile.getConstPool();
 AnnotationsAttribute attr = new AnnotationsAttribute(constPool, AnnotationsAttribute.visibleTag);
 Annotation annot = new Annotation("javax.xml.bind.annotation.XmlTransient",constPool); attr.addAnnotation(annot);
 CtField field = ctClass.getDeclaredField(fieldName); 
field.getFieldInfo().addAttribute(attr);
 System.out.println(field.getAnnotation(XmlTransient.class));
 ccFile.setVersionToJava5(); ctClass.writeFile(); 
}  

public static void main (String args[]) throws CannotCompileException, NotFoundException, IOException, SecurityException, NoSuchMethodException, ClassNotFoundException, JAXBException, NoSuchFieldException
{
   Person<Student> p = new Person<Student>();
 p.setName("XYZ"); 
Student s = new Student(); 
s.setName("ABC"); 
s.setId("239423"); 
p.setPayload(s);  
addAnnotationRunTime("RuntimeAnnotation.Person", "name");
  Field f = p.getClass().getDeclaredField("name"); 
System.out.println(f.getAnnotation(XmlTransient.class)); 
 JAXBContext context = JAXBContext.newInstance(p.getClass());
  Marshaller mr = context.createMarshaller(); 
mr.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE); 
 mr.marshal(p, System.out); 
} } 

And Person.java class is:

@XmlRootElement(name="Person")
 @XmlAccessorType(XmlAccessType.FIELD)
 @XmlSeeAlso({Student.class}) 
public class Person <T>
{  
private T payload;
  private String name;  
public void setPayload(T payload)
{
 this.payload = payload; 
} 
 public T getPayload()
{ 
return payload; 
}  
public void setName(String name)
{
 this.name = name; 
}
  public String getName()
{
 return name; 
} 
} 

In AssistAnnotationInjector.java, I am trying to add XmlTransient annotation to 'name' field. But the name field is still coming in marshalling output. Why is it so?

PS: marshal output is :

@javax.xml.bind.annotation.XmlTransient null <?xml version="1.0" encoding="UTF-8" standalone="yes"?> 
<Person> 
<payload xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:type="student"> 
<name>ABC</name> 
<id>239423</id>
 </payload> 
**<name>XYZ</name>** 
</Person> 

name tag was not expected to present in output..