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

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Here is the source code for org.apache.calcite.interpreter.ProjectNode.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.Project;
import org.apache.calcite.rex.RexNode;

import com.google.common.collect.ImmutableList;

/**
 * Interpreter node that implements a
 * {@link org.apache.calcite.rel.logical.LogicalFilter}.
 */
public class ProjectNode implements Node {
    private final ImmutableList<Scalar> projects;
    private final Source source;
    private final Sink sink;
    private final Context context;

    public ProjectNode(Interpreter interpreter, Project rel) {
        ImmutableList.Builder<Scalar> builder = ImmutableList.builder();
        for (RexNode node : rel.getProjects()) {
            builder.add(interpreter.compile(node));
        }
        this.projects = builder.build();
        this.source = interpreter.source(rel, 0);
        this.sink = interpreter.sink(rel);
        this.context = interpreter.createContext();
    }

    public void run() throws InterruptedException {
        Row row;
        while ((row = source.receive()) != null) {
            context.values = row.getValues();
            Object[] values = new Object[projects.size()];
            for (int i = 0; i < projects.size(); i++) {
                Scalar scalar = projects.get(i);
                values[i] = scalar.execute(context);
            }
            sink.send(new Row(values));
        }
    }
}

// End ProjectNode.java