assertEquals(1, ChangeLogParserFactory.getInstance().getParsers().size());
}
@Test
public void unregister_instance() {
ChangeLogParserFactory factory = ChangeLogParserFactory.getInstance();
factory.getParsers().clear();
assertEquals(0, factory.getParsers().size());
ChangeLogParser mockChangeLogParser = new MockChangeLogParser();
factory.register(new XMLChangeLogSAXParser());
factory.register(mockChangeLogParser);
factory.register(new SqlChangeLogParser());
assertEquals(3, factory.getParsers().size());
factory.unregister(mockChangeLogParser);
assertEquals(2, factory.getParsers().size());
}