| 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.AOrderedListSerializerDeserializer; |
| 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; |
| import edu.uci.ics.hyracks.dataflow.common.data.marshalling.IntegerSerializerDeserializer; |
| |
| public class GetItemDescriptor extends AbstractScalarFunctionDynamicDescriptor { |
| |
| private static final long serialVersionUID = 1L; |
| private final static FunctionIdentifier FID = new FunctionIdentifier(FunctionConstants.ASTERIX_NS, "get-item", 2, |
| true); |
| public static final IFunctionDescriptorFactory FACTORY = new IFunctionDescriptorFactory() { |
| public IFunctionDescriptor createFunctionDescriptor() { |
| return new GetItemDescriptor(); |
| } |
| }; |
| |
| @Override |
| public ICopyEvaluatorFactory createEvaluatorFactory(final ICopyEvaluatorFactory[] args) { |
| return new GetItemEvalFactory(args); |
| } |
| |
| @Override |
| public FunctionIdentifier getIdentifier() { |
| return FID; |
| } |
| |
| private static class GetItemEvalFactory implements ICopyEvaluatorFactory { |
| |
| private static final long serialVersionUID = 1L; |
| |
| private ICopyEvaluatorFactory listEvalFactory; |
| private ICopyEvaluatorFactory indexEvalFactory; |
| private final static byte SER_ORDEREDLIST_TYPE_TAG = ATypeTag.ORDEREDLIST.serialize(); |
| private final static byte SER_NULL_TYPE_TAG = ATypeTag.NULL.serialize(); |
| private byte serItemTypeTag; |
| private ATypeTag itemTag; |
| private boolean selfDescList = false; |
| |
| public GetItemEvalFactory(ICopyEvaluatorFactory[] args) { |
| this.listEvalFactory = args[0]; |
| this.indexEvalFactory = args[1]; |
| } |
| |
| @Override |
| public ICopyEvaluator createEvaluator(final IDataOutputProvider output) throws AlgebricksException { |
| return new ICopyEvaluator() { |
| |
| private DataOutput out = output.getDataOutput(); |
| private ArrayBackedValueStorage outInputList = new ArrayBackedValueStorage(); |
| private ArrayBackedValueStorage outInputIdx = new ArrayBackedValueStorage(); |
| private ICopyEvaluator evalList = listEvalFactory.createEvaluator(outInputList); |
| private ICopyEvaluator evalIdx = indexEvalFactory.createEvaluator(outInputIdx); |
| @SuppressWarnings("unchecked") |
| private ISerializerDeserializer<ANull> nullSerde = AqlSerializerDeserializerProvider.INSTANCE |
| .getSerializerDeserializer(BuiltinType.ANULL); |
| private int itemIndex; |
| private int itemOffset; |
| private int itemLength; |
| |
| @Override |
| public void evaluate(IFrameTupleReference tuple) throws AlgebricksException { |
| |
| try { |
| outInputList.reset(); |
| evalList.evaluate(tuple); |
| outInputIdx.reset(); |
| evalIdx.evaluate(tuple); |
| byte[] serOrderedList = outInputList.getByteArray(); |
| |
| if (serOrderedList[0] == SER_NULL_TYPE_TAG) { |
| nullSerde.serialize(ANull.NULL, out); |
| return; |
| } |
| |
| if (serOrderedList[0] != SER_ORDEREDLIST_TYPE_TAG) { |
| throw new AlgebricksException("List's get-item can not be called on values of type" |
| + EnumDeserializer.ATYPETAGDESERIALIZER.deserialize(serOrderedList[0])); |
| } |
| |
| itemIndex = IntegerSerializerDeserializer.getInt(outInputIdx.getByteArray(), 1); |
| if (itemIndex >= AOrderedListSerializerDeserializer.getNumberOfItems(serOrderedList)) { |
| out.writeByte(SER_NULL_TYPE_TAG); |
| return; |
| } |
| if (itemIndex < 0) |
| throw new AlgebricksException("Item index can be negative !!"); |
| |
| itemTag = EnumDeserializer.ATYPETAGDESERIALIZER.deserialize(serOrderedList[1]); |
| if (itemTag == ATypeTag.ANY) |
| selfDescList = true; |
| else |
| serItemTypeTag = serOrderedList[1]; |
| |
| itemOffset = AOrderedListSerializerDeserializer.getItemOffset(serOrderedList, itemIndex); |
| |
| if (selfDescList) { |
| itemTag = EnumDeserializer.ATYPETAGDESERIALIZER.deserialize(serOrderedList[itemOffset]); |
| itemLength = NonTaggedFormatUtil.getFieldValueLength(serOrderedList, itemOffset, itemTag, |
| true) + 1; |
| out.write(serOrderedList, itemOffset, itemLength); |
| } else { |
| itemLength = NonTaggedFormatUtil.getFieldValueLength(serOrderedList, itemOffset, itemTag, |
| false); |
| out.writeByte(serItemTypeTag); |
| out.write(serOrderedList, itemOffset, itemLength); |
| } |
| } catch (IOException e) { |
| throw new AlgebricksException(e); |
| } catch (AsterixException e) { |
| throw new AlgebricksException(e); |
| } |
| } |
| }; |
| } |
| |
| } |
| |
| } |