Bug 54737 Libraries dialog doesn't remember status of items in library tree
Preferences > Java > Build Path > User Libraries: The dialog does not seem to correctly remember the status of the items in the "Defined user libraries" tree. When I leave the dialog I close (un-cascade) all items. When I open the dialog again, most of the items are open (cascaded) again. This is disturbing because I cannot overview the items. It's like opening the Windows explorer with not only the drives shown but all folders being open.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/dialogfields/TreeListDialogField.java
*/
	public void setElements(List elements) {
		fElements= new ArrayList(elements);
		refresh();
		if (fTree != null) {
			fTree.expandToLevel(fTreeExpandLevel);
		}
		dialogFieldChanged();
	}
	/**
	* Gets the elements shown in the list.
	* The list returned is a copy, so it can be modified by the user.
	*/
	public List getElements() {
		return new ArrayList(fElements);
	}
	/**
	* Gets the element shown at the given index.
	*/
	public Object getElement(int index) {
		return fElements.get(index);
	}
	
	/**
	* Gets the index of an element in the list or -1 if element is not in list.
    */
	public int getIndexOfElement(Object elem) {
		return fElements.indexOf(elem);
	}	
	/**