listings "escapeoutsides"

Question

I know, it's escapeinsides. But how can I show only the part of code? Not by linerange? But by "word" range?

For example i will show only code from //<B> to //<qB>

//<A>
class A{
public A(){
  System.out.println("Hello from A");
}
//<qA>

//<B>
class B extends A{
  System.out.println("Hello from B");
}
//<qB>

//<C>
class C extends B{ 
 System.out.println("Hello from C");
}
//<qC>