private final SerializableFunction<Input, Iterable<Output>> javaImplementation;
private ProbabilisticDoubleInterval selectivity;
public FlatMapDescriptor(SerializableFunction<Input, Iterable<Output>> javaImplementation,
Class<Input> inputTypeClass,
Class<Output> outputTypeClass) {
<BUG>this(javaImplementation, inputTypeClass, outputTypeClass, null);
</BUG>
}
public FlatMapDescriptor(SerializableFunction<Input, Iterable<Output>> javaImplementation,
Class<Input> inputTypeClass,

private final SerializableFunction<Input, Iterable<Output>> javaImplementation;
private ProbabilisticDoubleInterval selectivity;
public FlatMapDescriptor(SerializableFunction<Input, Iterable<Output>> javaImplementation,
Class<Input> inputTypeClass,
Class<Output> outputTypeClass) {
this(javaImplementation, inputTypeClass, outputTypeClass, (ProbabilisticDoubleInterval) null);
}
public FlatMapDescriptor(SerializableFunction<Input, Iterable<Output>> javaImplementation,
Class<Input> inputTypeClass,
