Create XML (or JSON, HTML, ...) view for converters

I want to use a specific view for my object to render xml (or json or others)
Sample :
class MyClass{
String param1
String param2
Set param3
}

I want to render only param1 and 2 .
At this time, Ican create an object view :
class MyClassView1 {
String param1
String param2
mapping =

}

class MyClassView2

But why not :

class MyClass{
...
static rendering1 =

static rendering2 =

}

or better, create a outside class to do this mechanism.

Thanks a lot.