/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.beam.runners.direct;
import org.apache.beam.runners.direct.DirectGroupByKey.DirectGroupByKeyOnly;
import org.apache.beam.sdk.transforms.PTransform;
import org.apache.beam.sdk.values.PCollection;
/**
* A factory that creates {@link UncommittedBundle UncommittedBundles}.
*/
interface BundleFactory {
/**
* Create an {@link UncommittedBundle} from an empty input. Elements added to the bundle do not
* belong to a {@link PCollection}.
*
* <p>For use in creating inputs to root transforms.
*/
<T> UncommittedBundle<T> createRootBundle();
/**
* Create an {@link UncommittedBundle} from the specified input. Elements added to the bundle
* belong to the {@code output} {@link PCollection}.
*/
<T> UncommittedBundle<T> createBundle(PCollection<T> output);
/**
* Create an {@link UncommittedBundle} with the specified keys at the specified step. For use by
* {@link DirectGroupByKeyOnly} {@link PTransform PTransforms}. Elements added to the bundle
* belong to the {@code output} {@link PCollection}.
*/
<K, T> UncommittedBundle<T> createKeyedBundle(
StructuralKey<K> key, PCollection<T> output);
}