| /* |
| * Copyright 2009-2011 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.asterix.external.data.operator; |
| |
| import java.util.Map; |
| |
| import edu.uci.ics.asterix.external.data.adapter.api.IDatasourceReadAdapter; |
| import edu.uci.ics.asterix.om.types.IAType; |
| import edu.uci.ics.hyracks.api.application.ICCApplicationContext; |
| import edu.uci.ics.hyracks.api.constraints.IConstraintAcceptor; |
| import edu.uci.ics.hyracks.api.context.IHyracksTaskContext; |
| import edu.uci.ics.hyracks.api.dataflow.IOperatorNodePushable; |
| import edu.uci.ics.hyracks.api.dataflow.value.IRecordDescriptorProvider; |
| import edu.uci.ics.hyracks.api.dataflow.value.RecordDescriptor; |
| import edu.uci.ics.hyracks.api.exceptions.HyracksDataException; |
| import edu.uci.ics.hyracks.api.job.JobSpecification; |
| import edu.uci.ics.hyracks.dataflow.std.base.AbstractSingleActivityOperatorDescriptor; |
| import edu.uci.ics.hyracks.dataflow.std.base.AbstractUnaryOutputSourceOperatorNodePushable; |
| |
| public class ExternalDataScanOperatorDescriptor extends AbstractSingleActivityOperatorDescriptor { |
| private static final long serialVersionUID = 1L; |
| |
| private final String adapter; |
| private final Map<String, String> adapterConfiguration; |
| private final IAType atype; |
| private IDatasourceReadAdapter datasourceReadAdapter; |
| |
| public ExternalDataScanOperatorDescriptor(JobSpecification spec, String adapter, Map<String, String> arguments, |
| IAType atype, RecordDescriptor rDesc) { |
| super(spec, 0, 1); |
| recordDescriptors[0] = rDesc; |
| this.adapter = adapter; |
| this.adapterConfiguration = arguments; |
| this.atype = atype; |
| } |
| |
| @Override |
| public void contributeSchedulingConstraints(IConstraintAcceptor constraintAcceptor, ICCApplicationContext appCtx) { |
| |
| /* |
| Comment: The following code is commented out. This is because constraints are being set at compile time so that they can |
| be propagated to upstream Asterix operators. Hyracks has to provide a way to propagate constraints to upstream operators. |
| Once it is there, we will uncomment the following code. |
| |
| AlgebricksPartitionConstraint constraint = datasourceReadAdapter.getPartitionConstraint(); |
| switch (constraint.getPartitionConstraintType()) { |
| case ABSOLUTE: |
| String[] locations = ((AlgebricksAbsolutePartitionConstraint) constraint).getLocations(); |
| for (int i = 0; i < locations.length; ++i) { |
| constraintAcceptor.addConstraint(new Constraint(new PartitionLocationExpression(this.odId, i), |
| new ConstantExpression(locations[i]))); |
| } |
| constraintAcceptor.addConstraint(new Constraint(new PartitionCountExpression(this.odId), |
| new ConstantExpression(locations.length))); |
| |
| break; |
| case COUNT: |
| constraintAcceptor.addConstraint(new Constraint(new PartitionCountExpression(this.odId), |
| new ConstantExpression(((AlgebricksCountPartitionConstraint) constraint).getCount()))); |
| break; |
| default: |
| throw new IllegalStateException(" Constraint type :" + constraint.getPartitionConstraintType() |
| + " not supported"); |
| |
| }*/ |
| |
| } |
| |
| public IOperatorNodePushable createPushRuntime(IHyracksTaskContext ctx, |
| IRecordDescriptorProvider recordDescProvider, final int partition, int nPartitions) |
| throws HyracksDataException { |
| |
| try { |
| //datasourceReadAdapter = (IDatasourceReadAdapter) Class.forName(adapter).newInstance(); |
| datasourceReadAdapter.configure(adapterConfiguration, atype); |
| datasourceReadAdapter.initialize(ctx); |
| } catch (Exception e) { |
| throw new HyracksDataException("initialization of adapter failed", e); |
| } |
| return new AbstractUnaryOutputSourceOperatorNodePushable() { |
| @Override |
| public void initialize() throws HyracksDataException { |
| writer.open(); |
| try { |
| datasourceReadAdapter.getDataParser(partition).parse(writer); |
| } catch (Exception e) { |
| throw new HyracksDataException("exception during reading from external data source", e); |
| } finally { |
| writer.close(); |
| } |
| } |
| }; |
| } |
| |
| public void setDatasourceAdapter(IDatasourceReadAdapter adapterInstance) { |
| this.datasourceReadAdapter = adapterInstance; |
| } |
| } |