Bug 30630 nested source folders: unclear error message
20030129 create a jproject, a source folder s1 and a nested in it source folder s2 delete s1 open the 'new' wizard and try creating a source folder s1 the error message is very long and compilicated while it should be a simple warning saying 'You have a folder s1 - I will turn it into a source folder fo you' (and then it could automagically add excelusion filter so that s2 is still a source folder)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/buildpaths/SourceContainerWorkbookPage.java
fFoldersList.enableButton(IDX_EDIT, canEdit(selected));
		fFoldersList.enableButton(IDX_REMOVE, canRemove(selected));
	}
	
	private void removeEntry() {
		List selElements= fFoldersList.getSelectedElements();
		for (int i= selElements.size() - 1; i >= 0 ; i--) {
			Object elem= selElements.get(i);
			if (elem instanceof CPListElementAttribute) {
				CPListElementAttribute attrib= (CPListElementAttribute) elem;
				String key= attrib.getKey();
				Object value= key.equals(CPListElement.EXCLUSION) ? new Path[0] : null;
				attrib.getParent().setAttribute(key, value);
				selElements.remove(i);
			}
		}
		if (selElements.isEmpty()) {
			fFoldersList.refresh();
			fClassPathList.dialogFieldChanged(); 
		} else {
			fFoldersList.removeElements(selElements);
		}
	}
	
	private boolean canRemove(List selElements) {
		if (selElements.size() == 0) {
			return false;
		}
		for (int i= 0; i < selElements.size(); i++) {
			Object elem= (Object) selElements.get(i);