| package edu.uci.ics.asterix.runtime.evaluators.functions; |
| |
| import edu.uci.ics.asterix.common.functions.FunctionConstants; |
| import edu.uci.ics.asterix.formats.nontagged.AqlSerializerDeserializerProvider; |
| import edu.uci.ics.asterix.om.base.AInt32; |
| import edu.uci.ics.asterix.om.base.AMutableInt32; |
| 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.runtime.evaluators.base.AbstractScalarFunctionDynamicDescriptor; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.functions.FunctionIdentifier; |
| import edu.uci.ics.hyracks.algebricks.common.exceptions.AlgebricksException; |
| 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.data.std.primitive.UTF8StringPointable; |
| 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 java.io.DataOutput; |
| import java.io.IOException; |
| |
| public class StringLengthDescriptor extends AbstractScalarFunctionDynamicDescriptor { |
| |
| private static final long serialVersionUID = 1L; |
| public final static FunctionIdentifier FID = new FunctionIdentifier(FunctionConstants.ASTERIX_NS, "string-length", |
| 1); |
| public static final IFunctionDescriptorFactory FACTORY = new IFunctionDescriptorFactory() { |
| public IFunctionDescriptor createFunctionDescriptor() { |
| return new StringLengthDescriptor(); |
| } |
| }; |
| private final static byte SER_STRING_TYPE_TAG = ATypeTag.STRING.serialize(); |
| private final static byte SER_NULL_TYPE_TAG = ATypeTag.NULL.serialize(); |
| |
| @Override |
| public ICopyEvaluatorFactory createEvaluatorFactory(final ICopyEvaluatorFactory[] args) { |
| return new ICopyEvaluatorFactory() { |
| private static final long serialVersionUID = 1L; |
| |
| @Override |
| public ICopyEvaluator createEvaluator(final IDataOutputProvider output) throws AlgebricksException { |
| return new ICopyEvaluator() { |
| private AMutableInt32 result = new AMutableInt32(0); |
| private DataOutput out = output.getDataOutput(); |
| private ArrayBackedValueStorage outInput = new ArrayBackedValueStorage(); |
| private ICopyEvaluator eval = args[0].createEvaluator(outInput); |
| private String errorMessage = "This can not be an instance of string"; |
| @SuppressWarnings("unchecked") |
| private ISerializerDeserializer<ANull> nullSerde = AqlSerializerDeserializerProvider.INSTANCE |
| .getSerializerDeserializer(BuiltinType.ANULL); |
| @SuppressWarnings("unchecked") |
| private ISerializerDeserializer<AInt32> intSerde = AqlSerializerDeserializerProvider.INSTANCE |
| .getSerializerDeserializer(BuiltinType.AINT32); |
| |
| @Override |
| public void evaluate(IFrameTupleReference tuple) throws AlgebricksException { |
| |
| try { |
| outInput.reset(); |
| eval.evaluate(tuple); |
| byte[] serString = outInput.getByteArray(); |
| if (serString[0] == SER_STRING_TYPE_TAG) { |
| int len = UTF8StringPointable.getUTFLength(outInput.getByteArray(), 1); |
| result.setValue(len); |
| intSerde.serialize(result, out); |
| } else if (serString[0] == SER_NULL_TYPE_TAG) |
| nullSerde.serialize(ANull.NULL, out); |
| else { |
| throw new AlgebricksException(errorMessage); |
| } |
| } catch (IOException e1) { |
| throw new AlgebricksException(errorMessage); |
| } |
| } |
| }; |
| } |
| }; |
| } |
| |
| @Override |
| public FunctionIdentifier getIdentifier() { |
| return FID; |
| } |
| |
| } |