Examples with Twister2EmptySource org.apache.beam.runners.twister2.translation.wrappers.Twister2EmptySource used on opensource projects

Example 1 with Twister2EmptySource

use of org.apache.beam.runners.twister2.translation.wrappers.Twister2EmptySource in project beam by apache.

the class FlattenTranslatorBatch method translateNode.

@Override
public void translateNode(Flatten.PCollections<T> transform, Twister2BatchTranslationContext context) {
    Collection<PCollection<?>> pcs = context.getInputs().values();
    List<BatchTSetImpl<WindowedValue<T>>> tSets = new ArrayList<>();
    BatchTSetImpl<WindowedValue<T>> unionTSet;
    if (pcs.isEmpty()) {
        final TSetEnvironment tsetEnv = context.getEnvironment();
        unionTSet = ((BatchTSetEnvironment) tsetEnv).createSource(new Twister2EmptySource(), context.getOptions().getParallelism());
    } else {
        for (PValue pc : pcs) {
            BatchTSetImpl<WindowedValue<T>> curr = context.getInputDataSet(pc);
            tSets.add(curr);
        }
        BatchTSetImpl<WindowedValue<T>> first = tSets.remove(0);
        Collection<TSet<WindowedValue<T>>> others = new ArrayList<>();
        others.addAll(tSets);
        if (tSets.size() > 0) {
            unionTSet = first.union(others);
        } else {
            unionTSet = first;
        }
    }
    context.setOutputDataSet(context.getOutput(transform), unionTSet);
}