org.apache.calcite.interpreter.UnionNode.java Source code

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Here is the source code for org.apache.calcite.interpreter.UnionNode.java

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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.calcite.interpreter;

import org.apache.calcite.rel.core.Union;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.Sets;

import java.util.Set;

/**
 * Interpreter node that implements a
 * {@link org.apache.calcite.rel.core.Union}.
 */
public class UnionNode implements Node {
    private final ImmutableList<Source> sources;
    private final Sink sink;
    private final Union rel;

    public UnionNode(Interpreter interpreter, Union rel) {
        ImmutableList.Builder<Source> builder = ImmutableList.builder();
        for (int i = 0; i < rel.getInputs().size(); i++) {
            builder.add(interpreter.source(rel, i));
        }
        this.sources = builder.build();
        this.sink = interpreter.sink(rel);
        this.rel = rel;
    }

    public void run() throws InterruptedException {
        final Set<Row> rows = rel.all ? null : Sets.<Row>newHashSet();
        for (Source source : sources) {
            Row row;
            while ((row = source.receive()) != null) {
                if (rows == null || rows.add(row)) {
                    sink.send(row);
                }
            }
        }
    }
}

// End UnionNode.java