OnlineUtils { public static String getPostContingencyId(String stateId, String contingencyId) { Objects.requireNonNull(stateId, "state id is null"); Objects.requireNonNull(contingencyId, "contingency id is null"); return stateId + "-post-" + contingencyId; } private  OnlineUtils(); static Collection<Contingency> filterContingencies(List<Contingency> contingencies, List<String> contingenciesIds); static Set<String> getContingencyIds(List<Contingency> contingencies); static boolean isSafe(Collection<SecurityIndex> securityIndexes); static String getPostContingencyId(String stateId, String contingencyId); static UnitEnum getUnit(LimitViolationType type); static DateTime toCetDate(DateTime date); static LinkedHashMap<String, Double> getBranchesData(Network network);  }
@Test public void getPostContingencyIdTest() { assertEquals("state-post-contingency", OnlineUtils.getPostContingencyId("state", "contingency")); }