hyracks-dataflow-std/src/main/java/edu/uci/ics/hyracks/dataflow/std/connectors/OneToOneConnectorDescriptor.java

/*
 * Copyright 2009-2010 by The Regents of the University of California
 * Licensed 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 from
 * 
 *     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 edu.uci.ics.hyracks.dataflow.std.connectors;

import edu.uci.ics.hyracks.api.comm.IConnectionDemultiplexer;
import edu.uci.ics.hyracks.api.comm.IFrameReader;
import edu.uci.ics.hyracks.api.comm.IFrameWriter;
import edu.uci.ics.hyracks.api.constraints.IConstraintExpressionAcceptor;
import edu.uci.ics.hyracks.api.constraints.expressions.PartitionCountExpression;
import edu.uci.ics.hyracks.api.constraints.expressions.RelationalExpression;
import edu.uci.ics.hyracks.api.context.IHyracksStageletContext;
import edu.uci.ics.hyracks.api.dataflow.IEndpointDataWriterFactory;
import edu.uci.ics.hyracks.api.dataflow.IOperatorDescriptor;
import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor;
import edu.uci.ics.hyracks.api.exceptions.HyracksDataException;
import edu.uci.ics.hyracks.api.job.JobPlan;
import edu.uci.ics.hyracks.api.job.JobSpecification;
import edu.uci.ics.hyracks.dataflow.common.comm.NonDeterministicFrameReader;
import edu.uci.ics.hyracks.dataflow.std.base.AbstractConnectorDescriptor;

public class OneToOneConnectorDescriptor extends AbstractConnectorDescriptor {
    private static final long serialVersionUID = 1L;

    public OneToOneConnectorDescriptor(JobSpecification spec) {
        super(spec);
    }

    @Override
    public IFrameWriter createSendSideWriter(IHyracksStageletContext ctx, RecordDescriptor recordDesc,
            IEndpointDataWriterFactory edwFactory, int index, int nProducerPartitions, int nConsumerPartitions)
            throws HyracksDataException {
        return edwFactory.createFrameWriter(index);
    }

    @Override
    public IFrameReader createReceiveSideReader(IHyracksStageletContext ctx, RecordDescriptor recordDesc,
            IConnectionDemultiplexer demux, int index, int nProducerPartitions, int nConsumerPartitions)
            throws HyracksDataException {
        return new NonDeterministicFrameReader(ctx, demux);
    }

    @Override
    public void contributeSchedulingConstraints(IConstraintExpressionAcceptor constraintAcceptor, JobPlan plan) {
        JobSpecification jobSpec = plan.getJobSpecification();
        IOperatorDescriptor consumer = jobSpec.getConsumer(this);
        IOperatorDescriptor producer = jobSpec.getProducer(this);

        constraintAcceptor.addConstraintExpression(new RelationalExpression(new PartitionCountExpression(consumer
                .getOperatorId()), new PartitionCountExpression(producer.getOperatorId()),
                RelationalExpression.Operator.EQUAL));
    }
}