### Question:
FileOverrideSource extends AbstractSource implements OverrideSource, PollableSource<byte[]>, WatchableSource<Path> { public static Builder builder() { return new Builder(); } FileOverrideSource(Builder builder); @Override boolean exists(); @Override Optional<ConfigContent.OverrideContent> load(); @Override boolean isModified(byte[] stamp); @Override Optional<PollingStrategy> pollingStrategy(); @Override Path target(); @Override Optional<ChangeWatcher<Object>> changeWatcher(); @Override Class<Path> targetType(); static FileOverrideSource create(Config metaConfig); static Builder builder();  }### Answer:
@Test public void testBuilder() { OverrideSource overrideSource = OverrideSources.file("overrides.properties").build(); assertThat(overrideSource, notNullValue()); }