What is subclassing?
Subclassing means to define a new class that has the properties of an old class (the "superclass") with some changes.
In this case, your original responder is saying something like this:
Say you have a base class Base
which has a method getTwo
like so:
class Base { public int getTwo(){ return 2;}}
You decide you want a new class that still have a method getTwo
but that returns the string "two" instead of the number 2. You could define it as
class Subclass extends Base { public String getTwo() { return "two"; }}
We say Subclass
is a subclass of -- or more commonly, "is a kind of" -- Base
.
Beyond that, you'd be best off to read a book on object-oriented programming with Java. I'm fond of Thinking in Java, which has the added advantage that it's available freely on line.
@Charlie Martin has explained what subclassing means.
However, it is not clear that you've been given good advice. If you are creating the XML document by assembling a DOM in memory, a better approach would be to create a helper class with static methods that perform the sequence of DOM node operations that you need to do.
In short Answer : A Superclass can be Subclassed - That means for a specific class we can find/create a subclass that extend it.