### Question:
LiquibaseHelper { static List<ChangeSet> filterChangeSets(final List<ChangeSet> changeSets) { final List<ChangeSet> result = new ArrayList<>(); for (final ChangeSet changeSet : changeSets) { if (!isIgnoredChangeSet(changeSet)) { result.add(changeSet); } } return result; } LiquibaseHelper(final Map<String, String> props);   LiquibaseHelper(
            final Map<String, String> props,
            final ResourceAccessor resourceAccessor,
            final File resourcesDir,
            final String masterChangeLogName); File getResourcesDir(); File getMasterChangeLogFile(); void migrate(); File generateMigrations();  }### Answer:
@Test public void testFilterChangeSets() { final DropTableChange c1 = new DropTableChange(); c1.setTableName("foo"); final ChangeSet cs1 = new ChangeSet(null); cs1.addChange(c1); final DropTableChange c2 = new DropTableChange(); c2.setTableName("JGROUPSPING"); final ChangeSet cs2 = new ChangeSet(null); cs2.addChange(c2); final List<ChangeSet> original = Arrays.asList(cs1, cs2); final List<ChangeSet> filtered = LiquibaseHelper.filterChangeSets(original); assertEquals(1, filtered.size()); assertEquals(c1, filtered.get(0).getChanges().get(0)); }