Need help: Mysterious initialization behaviour
I subclassed a class UI_ProgressDialog with the class
UI_MultiProcessProgressDialog.
This class defines the following constructor:
public UI_MultiProcessProgressDialog(Frame owner, String title, String header,boolean showTextArea, boolean showProgressLabel,boolean autoClose)
{
super(owner, title, header, showTextArea,showProgressLabel, autoClose);
}
This constructor calls the superclass constructor which calls a method named initGUI. This method is overriden in the subclass UI_MUltiProcessProgressDialog and is being called within the call to the super class constructor of the superclass UI_ProgressDialog.
This initGUI method initializes a class attribute defined in
the subclass UI_MultiProcessProgressDialog. Everything works fine but when the constructor is being processed,
the regarding attribute is reset to null.
If the class attribute is defined as shown here:
Object o;
everything works as it should.
But if the regarding attribute is defined as :
Object o = null;
then the class crashes with a null pointer exception although the attribute has been initialized in the initGUI method.
What's the difference between these two initializations ?
It seems that the initialization of the class attributes is being processed after the constructor respective superclass constructor call. Can someone explain this to me ? Its urgent !!!
