public static PartitionGroupReleaseStrategy.Factory loadPartitionGroupReleaseStrategyFactory(
            final Configuration configuration) {
        final boolean partitionReleaseDuringJobExecution =
                configuration.get(JobManagerOptions.PARTITION_RELEASE_DURING_JOB_EXECUTION);
        if (partitionReleaseDuringJobExecution) {
            return new RegionPartitionGroupReleaseStrategy.Factory();
        } else {
            return new NotReleasingPartitionGroupReleaseStrategy.Factory();
        }
    }
@Test
    public void featureEnabledByDefault() {
        final Configuration emptyConfiguration = new Configuration();
        final PartitionGroupReleaseStrategy.Factory factory =
                PartitionGroupReleaseStrategyFactoryLoader.loadPartitionGroupReleaseStrategyFactory(
                        emptyConfiguration);

        assertThat(factory).isInstanceOf(RegionPartitionGroupReleaseStrategy.Factory.class);
    }