What is the difference between removeAllElements() and clear() for DefaultListModel?
What is the difference between removeAllElements()
and clear()
method of DefaultListModel
in java swing?
The java docs for DefaultListModel says :-
public void clear()
Removes all of the elements from this list. T开发者_C百科he list will be empty after this call returns (unless it throws an exception).
and
public void removeAllElements()
Removes all components from this list and sets its size to zero.
So both basically removes all elements from list so what is the difference? How to decide when to use which?
They are both same.
DefaultListModel
uses a Vector
under the hood.
The clear() method was added later when Vector was re-written to fit into the Collection API's.
With version 1.3 the Collections API
made its' entrance so the Vector
was re-written to fit into the List
interface.
In order for it to be backwards compatible, they simply forwarded the calls to the old existing methods where available & possible.
EDIT
From Java Source:
/** * Removes all components from this list and sets its size to zero. * <blockquote> * <b>Note:</b> Although this method is not deprecated, the preferred * method to use is <code>clear</code>, which implements the * <code>List</code> interface defined in the 1.2 Collections framework. * </blockquote> * * @see #clear() * @see Vector#removeAllElements() */
public void removeAllElements() {
int index1 = delegate.size()-1;
delegate.removeAllElements();
if (index1 >= 0) {
fireIntervalRemoved(this, 0, index1);
}
}
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