| package edu.uci.ics.asterix.runtime.evaluators.functions; |
| |
| import edu.uci.ics.asterix.om.functions.AsterixBuiltinFunctions; |
| import edu.uci.ics.asterix.om.functions.IFunctionDescriptor; |
| import edu.uci.ics.asterix.om.functions.IFunctionDescriptorFactory; |
| import edu.uci.ics.asterix.om.types.BuiltinType; |
| import edu.uci.ics.asterix.runtime.evaluators.base.AbstractScalarFunctionDynamicDescriptor; |
| import edu.uci.ics.asterix.runtime.evaluators.common.GramTokensEvaluator; |
| 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.data.std.api.IDataOutputProvider; |
| import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.HashedUTF8NGramTokenFactory; |
| import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.ITokenFactory; |
| import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.NGramUTF8StringBinaryTokenizer; |
| |
| public class CountHashedGramTokensDescriptor extends AbstractScalarFunctionDynamicDescriptor { |
| |
| private static final long serialVersionUID = 1L; |
| public static final IFunctionDescriptorFactory FACTORY = new IFunctionDescriptorFactory() { |
| public IFunctionDescriptor createFunctionDescriptor() { |
| return new CountHashedGramTokensDescriptor(); |
| } |
| }; |
| |
| @Override |
| public FunctionIdentifier getIdentifier() { |
| return AsterixBuiltinFunctions.COUNTHASHED_GRAM_TOKENS; |
| } |
| |
| @Override |
| public ICopyEvaluatorFactory createEvaluatorFactory(final ICopyEvaluatorFactory[] args) throws AlgebricksException { |
| return new ICopyEvaluatorFactory() { |
| private static final long serialVersionUID = 1L; |
| |
| @Override |
| public ICopyEvaluator createEvaluator(IDataOutputProvider output) throws AlgebricksException { |
| ITokenFactory tokenFactory = new HashedUTF8NGramTokenFactory(); |
| NGramUTF8StringBinaryTokenizer tokenizer = new NGramUTF8StringBinaryTokenizer(3, true, false, true, |
| tokenFactory); |
| return new GramTokensEvaluator(args, output, tokenizer, BuiltinType.AINT32); |
| } |
| }; |
| } |
| |
| } |