public boolean containsDatabase(final String databaseName) {
        return databases.containsKey(databaseName);
    }
@Test
    void assertContainsDatabase() {
        ShardingSphereRule globalRule = mock(ShardingSphereRule.class);
        ShardingSphereDatabase database = mockDatabase(mock(ResourceMetaData.class, RETURNS_DEEP_STUBS), new MockedDataSource(), globalRule);
        Map<String, ShardingSphereDatabase> databases = new HashMap<>(Collections.singletonMap("foo_db", database));
        ConfigurationProperties configProps = new ConfigurationProperties(new Properties());
        ShardingSphereMetaData metaData = new ShardingSphereMetaData(databases, mock(ResourceMetaData.class), new RuleMetaData(Collections.singleton(globalRule)), configProps);
        assertTrue(metaData.containsDatabase("foo_db"));
    }