asterix-runtime/src/main/java/edu/uci/ics/asterix/runtime/evaluators/functions/FieldAccessByIndexDescriptor.java

package edu.uci.ics.asterix.runtime.evaluators.functions;

import edu.uci.ics.asterix.common.functions.FunctionConstants;
import edu.uci.ics.asterix.om.functions.IFunctionDescriptor;
import edu.uci.ics.asterix.om.functions.IFunctionDescriptorFactory;
import edu.uci.ics.asterix.om.types.ARecordType;
import edu.uci.ics.asterix.runtime.evaluators.base.AbstractScalarFunctionDynamicDescriptor;
import edu.uci.ics.asterix.runtime.evaluators.common.FieldAccessByIndexEvalFactory;
import edu.uci.ics.hyracks.algebricks.core.algebra.functions.FunctionIdentifier;
import edu.uci.ics.hyracks.algebricks.runtime.base.ICopyEvaluatorFactory;

public class FieldAccessByIndexDescriptor extends AbstractScalarFunctionDynamicDescriptor {

    private static final long serialVersionUID = 1L;
    private static final FunctionIdentifier FID = new FunctionIdentifier(FunctionConstants.ASTERIX_NS,
            "field-access-by-index", 2);
    public static final IFunctionDescriptorFactory FACTORY = new IFunctionDescriptorFactory() {
        public IFunctionDescriptor createFunctionDescriptor() {
            return new FieldAccessByIndexDescriptor();
        }
    };

    private ARecordType recType;

    public void reset(ARecordType recType) {
        this.recType = recType;
    }

    @Override
    public FunctionIdentifier getIdentifier() {
        return FID;
    }

    @Override
    public ICopyEvaluatorFactory createEvaluatorFactory(ICopyEvaluatorFactory[] args) {
        return new FieldAccessByIndexEvalFactory(args[0], args[1], recType);
    }

}