Bug 30727 exclusion filters: cannot remove [build path]
20030129 create a jproject and a src folder in it add 2 packages to it a.b and c.d exclude c/d/ from the classpath open the java build path dialog, select the source folders expand the tree node select 'Exclusion filter: /c/d/' press 'Remove' seems to be removed, right? wrong. open the dialog again - the filter for /c/d is still there
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/buildpaths/LibrariesWorkbookPage.java
if (!cplist.contains(curr) && !elementsToAdd.contains(curr)) {
					elementsToAdd.add(curr);
					addAttachmentsFromExistingLibs(curr);
				}
			}
			fLibrariesList.addElements(elementsToAdd);
			fLibrariesList.postSetSelection(new StructuredSelection(libentries));
		}
	}
	
	protected void libaryPageDoubleClicked(TreeListDialogField field) {
		List selection= fLibrariesList.getSelectedElements();
		if (canEdit(selection)) {
			editEntry();
		}
	}
	private void removeEntry() {
		List selElements= fLibrariesList.getSelectedElements();
		for (int i= selElements.size() - 1; i >= 0 ; i--) {
			Object elem= selElements.get(i);
			if (elem instanceof CPListElementAttribute) {
				CPListElementAttribute attrib= (CPListElementAttribute) elem;
				attrib.setValue(null);
				selElements.remove(i);
			}
		}
		if (selElements.isEmpty()) {
			fLibrariesList.refresh();
		} else {
			fLibrariesList.removeElements(selElements);