Examples with QueryIterator org.apache.jena.sparql.engine.QueryIterator used on opensource projects

Example 46 with QueryIterator

use of org.apache.jena.sparql.engine.QueryIterator in project jena by apache.

the class EvaluatorSimple method groupBy.

@Override
public Table groupBy(Table table, VarExprList groupVars, List<ExprAggregator> aggregators) {
    QueryIterator qIter = table.iterator(getExecContext());
    qIter = new QueryIterGroup(qIter, groupVars, aggregators, getExecContext());
    return new TableN(qIter);
}

Example 47 with QueryIterator

use of org.apache.jena.sparql.engine.QueryIterator in project jena by apache.

the class EvaluatorSimple method filter.

@Override
public Table filter(ExprList expressions, Table table) {
    if (debug) {
        System.out.println("Restriction");
        System.out.println(expressions);
        dump(table);
    }
    QueryIterator iter = table.iterator(execCxt);
    List<Binding> output = new ArrayList<>();
    for (; iter.hasNext(); ) {
        Binding b = iter.nextBinding();
        if (expressions.isSatisfied(b, execCxt))
            output.add(b);
    }
    return new TableN(new QueryIterPlainWrapper(output.iterator(), execCxt));
}

Example 48 with QueryIterator

use of org.apache.jena.sparql.engine.QueryIterator in project jena by apache.

the class EvaluatorSimple method minusWorker.

private Table minusWorker(Table tableLeft, Table tableRight) {
    // Minus(Ω1, Ω2) = { μ | μ in Ω1 such that for all μ' in Ω2, either μ and μ' are not compatible or dom(μ) and dom(μ') are disjoint }
    TableN results = new TableN();
    QueryIterator iterLeft = tableLeft.iterator(execCxt);
    for (; iterLeft.hasNext(); ) {
        Binding bindingLeft = iterLeft.nextBinding();
        boolean includeThisRow = true;
        // Find a reason not to include the row.
        // That's is not disjoint and not compatible.
        QueryIterator iterRight = tableRight.iterator(execCxt);
        for (; iterRight.hasNext(); ) {
            Binding bindingRight = iterRight.nextBinding();
            if (Algebra.disjoint(bindingLeft, bindingRight))
                // Disjoint - not a reason to exclude
                continue;
            if (!Algebra.compatible(bindingLeft, bindingRight))
                // Compatible - not a reason to exclude.
                continue;
            includeThisRow = false;
            break;
        }
        iterRight.close();
        if (includeThisRow)
            results.addBinding(bindingLeft);
    }
    iterLeft.close();
    return results;
}

Example 49 with QueryIterator

use of org.apache.jena.sparql.engine.QueryIterator in project jena by apache.

the class OpExecutor method execute.

protected QueryIterator execute(OpGroup opGroup, QueryIterator input) {
    QueryIterator qIter = exec(opGroup.getSubOp(), input);
    qIter = new QueryIterGroup(qIter, opGroup.getGroupVars(), opGroup.getAggregators(), execCxt);
    return qIter;
}

Example 50 with QueryIterator

use of org.apache.jena.sparql.engine.QueryIterator in project jena by apache.

the class OpExecutor method execute.

protected QueryIterator execute(OpSlice opSlice, QueryIterator input) {
    QueryIterator qIter = exec(opSlice.getSubOp(), input);
    qIter = new QueryIterSlice(qIter, opSlice.getStart(), opSlice.getLength(), execCxt);
    return qIter;
}