| 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.ITokenFactory; |
| import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.NGramUTF8StringBinaryTokenizer; |
| import edu.uci.ics.hyracks.storage.am.invertedindex.tokenizers.UTF8NGramTokenFactory; |
| |
| public class GramTokensDescriptor extends AbstractScalarFunctionDynamicDescriptor { |
| |
| private static final long serialVersionUID = 1L; |
| public static final IFunctionDescriptorFactory FACTORY = new IFunctionDescriptorFactory() { |
| public IFunctionDescriptor createFunctionDescriptor() { |
| return new GramTokensDescriptor(); |
| } |
| }; |
| |
| @Override |
| public FunctionIdentifier getIdentifier() { |
| return AsterixBuiltinFunctions.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 UTF8NGramTokenFactory(); |
| NGramUTF8StringBinaryTokenizer tokenizer = new NGramUTF8StringBinaryTokenizer(3, true, true, true, |
| tokenFactory); |
| return new GramTokensEvaluator(args, output, tokenizer, BuiltinType.ASTRING); |
| } |
| }; |
| } |
| |
| } |