| package edu.uci.ics.asterix.runtime.evaluators.functions; |
| |
| import java.io.DataOutput; |
| import java.io.IOException; |
| |
| import edu.uci.ics.asterix.common.exceptions.AsterixException; |
| import edu.uci.ics.asterix.common.functions.FunctionConstants; |
| import edu.uci.ics.asterix.dataflow.data.nontagged.serde.ARecordSerializerDeserializer; |
| import edu.uci.ics.asterix.formats.nontagged.AqlSerializerDeserializerProvider; |
| import edu.uci.ics.asterix.om.base.ANull; |
| import edu.uci.ics.asterix.om.functions.IFunctionDescriptor; |
| import edu.uci.ics.asterix.om.functions.IFunctionDescriptorFactory; |
| import edu.uci.ics.asterix.om.types.ATypeTag; |
| import edu.uci.ics.asterix.om.types.BuiltinType; |
| import edu.uci.ics.asterix.om.types.EnumDeserializer; |
| import edu.uci.ics.asterix.om.util.NonTaggedFormatUtil; |
| import edu.uci.ics.asterix.runtime.evaluators.base.AbstractScalarFunctionDynamicDescriptor; |
| import edu.uci.ics.hyracks.algebricks.common.exceptions.AlgebricksException; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.functions.FunctionIdentifier; |
| import edu.uci.ics.hyracks.algebricks.runtime.base.ICopyEvaluator; |
| import edu.uci.ics.hyracks.algebricks.runtime.base.ICopyEvaluatorFactory; |
| import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer; |
| import edu.uci.ics.hyracks.dataflow.common.data.accessors.ArrayBackedValueStorage; |
| import edu.uci.ics.hyracks.dataflow.common.data.accessors.IDataOutputProvider; |
| import edu.uci.ics.hyracks.dataflow.common.data.accessors.IFrameTupleReference; |
| |
| public class FieldAccessByNameDescriptor extends AbstractScalarFunctionDynamicDescriptor { |
| |
| private static final long serialVersionUID = 1L; |
| private static final FunctionIdentifier FID = new FunctionIdentifier(FunctionConstants.ASTERIX_NS, |
| "field-access-by-name", 2, true); |
| public static final IFunctionDescriptorFactory FACTORY = new IFunctionDescriptorFactory() { |
| public IFunctionDescriptor createFunctionDescriptor() { |
| return new FieldAccessByNameDescriptor(); |
| } |
| }; |
| |
| @Override |
| public FunctionIdentifier getIdentifier() { |
| return FID; |
| } |
| |
| @Override |
| public ICopyEvaluatorFactory createEvaluatorFactory(ICopyEvaluatorFactory[] args) { |
| return new FieldAccessByNameEvalFactory(args[0], args[1]); |
| } |
| |
| private static class FieldAccessByNameEvalFactory implements ICopyEvaluatorFactory { |
| |
| private static final long serialVersionUID = 1L; |
| |
| private ICopyEvaluatorFactory recordEvalFactory; |
| private ICopyEvaluatorFactory fldNameEvalFactory; |
| |
| private final static byte SER_NULL_TYPE_TAG = ATypeTag.NULL.serialize(); |
| private final static byte SER_RECORD_TYPE_TAG = ATypeTag.RECORD.serialize(); |
| |
| public FieldAccessByNameEvalFactory(ICopyEvaluatorFactory recordEvalFactory, ICopyEvaluatorFactory fldNameEvalFactory) { |
| this.recordEvalFactory = recordEvalFactory; |
| this.fldNameEvalFactory = fldNameEvalFactory; |
| } |
| |
| @Override |
| public ICopyEvaluator createEvaluator(final IDataOutputProvider output) throws AlgebricksException { |
| return new ICopyEvaluator() { |
| |
| private DataOutput out = output.getDataOutput(); |
| |
| private ArrayBackedValueStorage outInput0 = new ArrayBackedValueStorage(); |
| private ArrayBackedValueStorage outInput1 = new ArrayBackedValueStorage(); |
| private ICopyEvaluator eval0 = recordEvalFactory.createEvaluator(outInput0); |
| private ICopyEvaluator eval1 = fldNameEvalFactory.createEvaluator(outInput1); |
| @SuppressWarnings("unchecked") |
| private ISerializerDeserializer<ANull> nullSerde = AqlSerializerDeserializerProvider.INSTANCE |
| .getSerializerDeserializer(BuiltinType.ANULL); |
| private int fieldValueOffset; |
| private int fieldValueLength; |
| private ATypeTag fieldValueTypeTag = ATypeTag.NULL; |
| |
| @Override |
| public void evaluate(IFrameTupleReference tuple) throws AlgebricksException { |
| |
| try { |
| outInput0.reset(); |
| eval0.evaluate(tuple); |
| outInput1.reset(); |
| eval1.evaluate(tuple); |
| byte[] serRecord = outInput0.getByteArray(); |
| |
| if (serRecord[0] == SER_NULL_TYPE_TAG) { |
| nullSerde.serialize(ANull.NULL, out); |
| return; |
| } |
| |
| if (serRecord[0] != SER_RECORD_TYPE_TAG) { |
| throw new AlgebricksException("Field accessor is not defined for values of type" |
| + EnumDeserializer.ATYPETAGDESERIALIZER.deserialize(serRecord[0])); |
| } |
| |
| byte[] serFldName = outInput1.getByteArray(); |
| fieldValueOffset = ARecordSerializerDeserializer.getFieldOffsetByName(serRecord, serFldName); |
| if (fieldValueOffset < 0) { |
| out.writeByte(ATypeTag.NULL.serialize()); |
| return; |
| } |
| |
| fieldValueTypeTag = EnumDeserializer.ATYPETAGDESERIALIZER |
| .deserialize(serRecord[fieldValueOffset]); |
| fieldValueLength = NonTaggedFormatUtil.getFieldValueLength(serRecord, fieldValueOffset, |
| fieldValueTypeTag, true) + 1; |
| out.write(serRecord, fieldValueOffset, fieldValueLength); |
| |
| } catch (IOException e) { |
| throw new AlgebricksException(e); |
| } catch (AsterixException e) { |
| throw new AlgebricksException(e); |
| } |
| } |
| }; |
| } |
| |
| } |
| } |