java - JAXB Marshall XML Profile Filter -

i have need marshall object xml using jaxb.

the marshall / unmarshall code works fine, want filter resulting xml based on annotation.

xmlprofile.java

@retention (runtime) @target({type, method, field}) public @interface xmlprofile {     string[] value(); } 

foopojo.java

@xmlrootelement @xmlaccessortype(xmlaccesstype.field) public class foopojo {      @xmlelement     @xmlprofile("config")     public string bar;      @xmlelement     @xmlprofile("operational")     public string bartender;      @xmlelement     @xmlprofile({"config", "operational"})     public string spy;  } 

i read jaxb documentation, have not found examples / topics on how inject code marshall process, different adapter or eventhandlers.

in particular read event handlers, found support of before marshal / after marshal events.

i expected found beforefieldmarshal event not possible, figured write piece of code scans current entity , set null properties not matching current profile:

private class profilelistener extends marshaller.listener {      private string profile;      public profilelistener(string profile) {         this.profile = profile;     }      @override     public void beforemarshal(object source) {         if (source == null || profile == null || profile.length() == 0) return;          field[] fields = source.getclass().getfields();         (field f : fields){             xmlprofile xmlprofile = f.getannotation(xmlprofile.class);             if (xmlprofile == null) continue;              string[] annvalues = xmlprofile.value();             if (annvalues == null                  || annvalues.length == 0                  || findinarray(annvalues)) {                 continue;             }              // remove object             f.setaccessible(true);             try {                 f.set(source, null);             } catch (exception e) {                 e.printstacktrace();             }         }          super.beforemarshal(source); //to change body of generated methods, choose tools | templates.     }      private boolean findinarray(string[] annvalues){         (string annval : annvalues) {             if (profile.equalsignorecase(annval)){                 return true;             }         }         return false;     }  } 

the code works fine, nested object, code obtain:

working pojo

foopojo foopojo = new foopojo(); foopojo.bar = "tijuana cafe"; foopojo.bartender = "cynthia"; foopojo.spy = "antony fisco"; foopojo.phone = "555 555 555"; 

** resulting xml config profile:**

<foopojo>     <bar>tijuana cafe</bar>     <spy>antony fisco</spy>     <phone>555 555 555</phone> </foopojo> 

** resulting xml operational profile:**

<foopojo>     <bartender>cynthia</bartender>     <spy>antony fisco</spy>     <phone>555 555 555</phone> </foopojo> 

but has functional bug don't know how solve: pojo updated code, setting null properties.

is there better way that? can clone object , work on it, i'm not sure right way.