org.apache.kafka.streams.kstream.internals.graph.NodesWithRelaxedNullKeyJoinDownstream Maven / Gradle / Ivy
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* 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.kafka.streams.kstream.internals.graph;
import java.util.HashSet;
import java.util.Set;
import java.util.stream.Collectors;
public class NodesWithRelaxedNullKeyJoinDownstream {
private final HashSet visited;
private final HashSet nonOptimizable;
private final GraphNode start;
public NodesWithRelaxedNullKeyJoinDownstream(final GraphNode root) {
this.start = root;
this.visited = new HashSet<>();
this.nonOptimizable = new HashSet<>();
}
public Set> find() {
traverseGraph(this.start);
return visited.stream()
.filter(node -> node instanceof BaseRepartitionNode && !nonOptimizable.contains(node))
.map(node -> (BaseRepartitionNode) node)
.collect(Collectors.toSet());
}
private void traverseGraph(final GraphNode node) {
if (!visited.contains(node)) {
for (final GraphNode child : node.children()) {
traverseGraph(child);
if (child.labels().contains(GraphNode.Label.NULL_KEY_RELAXED_JOIN) || nonOptimizable.contains(child)) {
nonOptimizable.add(node);
}
}
visited.add(node);
}
}
}