First Transformations

[Dan Davis]

Hi guys, I'm writing my first Transform, and I'm having trouble with a
count query.
arq.qparse doesn't parse and print my count query, so  I cannot get much
feedback whether I'm doing the right thing or not.

A limit query seems simple enough, however:


package gov.nih.nlm.lode.service;

import com.hp.hpl.jena.sparql.algebra.Op;
import com.hp.hpl.jena.sparql.algebra.TransformBase;
import com.hp.hpl.jena.sparql.algebra.op.OpProject;
import com.hp.hpl.jena.sparql.algebra.op.OpSlice;

public class LimitTransform extends TransformBase {
    private long offset;
    private long limit;

    public LimitTransform(long limit, long offset) {
        this.limit = limit;
        this.offset = offset;
    }
    public LimitTransform(long limit) {
        this(limit, 0);
    }

    @Override
    public Op transform(OpProject opProject, Op subOp) {
        return new OpSlice(opProject, offset, limit);
    }
}