org.apache.jena.sparql.syntax.ElementData Java Examples

@Override
public void visit(ElementData el) {
    final NodeExprNormalizer nenzer = new NodeExprNormalizer();
    final ElementData nzed = new ElementData();
    final List<Var> vars = el.getVars();
    vars.forEach((v) -> {
        nzed.add(v);
    });
    el.getRows().forEach((b) -> {
        final BindingHashMap binding = new BindingHashMap();
        vars.forEach((v) -> {
            final Node n = b.get(v);
            if (n != null) {
                n.visitWith(nenzer);
                binding.add(v, nenzer.getResult());
            }
        });
        nzed.add(binding);
    });
    endVisit(nzed, nenzer);
}
 

private ElementData mergeValues(final ElementData qData, final List<Var> variables, final List<Binding> values) {
	if (values.isEmpty()) {
		return qData;
	}
	List<Var> vars = qData.getVars();
	if (!Collections.disjoint(vars, variables)) {
		throw new SPARQLExtException("Variables " + vars.retainAll(variables) + "were already bound.");
	}
	ElementData data = new ElementData();
	qData.getVars().forEach(data::add);
	variables.forEach(data::add);
	qData.getRows().forEach((qbinding) -> {
		values.forEach((binding) -> {
			BindingHashMap newb = new BindingHashMap(qbinding);
			variables.forEach((v) -> newb.add(v, binding.get(v)));
			data.add(newb);
		});
	});
	return data;
}
 

private static ElementData compress(List<Binding> input) {
    ElementData el = new ElementData();

    if (input.size() < 10) {
        input.forEach((b) -> {
            addCompressedToElementData(el, b);
        });
        return el;
    }
    for (int i = 0; i < 5; i++) {
        addCompressedToElementData(el, input.get(i));
    }
    BindingMap binding = BindingFactory.create();
    Node n = NodeFactory.createLiteral("[ " + (input.size() - 10) + " more ]");
    el.getVars().forEach((v) -> binding.add(v, n));
    el.add(binding);
    for (int i = input.size() - 5; i < input.size(); i++) {
        addCompressedToElementData(el, input.get(i));
    }
    return el;
}
 

private static ElementData compress(List<Var> variables, List<Binding> input) {
    ElementData el = new ElementData();
    variables.forEach(el::add);
    if (input.size() < 10) {
        input.forEach((b) -> el.add(compress(variables, b)));
        return el;
    }
    for (int i = 0; i < 5; i++) {
        el.add(compress(variables, input.get(i)));
    }
    BindingMap binding = BindingFactory.create();
    Node n = NodeFactory.createLiteral("[ " + (input.size() - 10) + " more ]");
    variables.forEach((v) -> binding.add(v, n));
    el.add(binding);
    for (int i = input.size() - 5; i < input.size(); i++) {
        el.add(compress(variables, input.get(i)));
    }
    return el;
}
 

@Test
public void testQueryAddValuesInQueryPattern() {
	List<Var> header = vars("a", "b");
	Binding b1 = binding(header, "1", "2");
	Binding b2 = binding(header, "3", "4");

	Query q = QueryFactory.create("SELECT * {}");
	ElementGroup group = new ElementGroup();
	ElementData table = new ElementData();
	table.add(Var.alloc("a"));
	table.add(Var.alloc("b"));
	table.add(b1);
	table.add(b2);
	group.addElement(q.getQueryPattern());
	group.addElement(table);
	q.setQueryPattern(group);
	ResultSet rs = QueryExecutionFactory.create(q, 
			ModelFactory.createDefaultModel()).execSelect();

	assertEquals(Arrays.asList(new String[]{"a","b"}), rs.getResultVars());
	assertTrue(rs.hasNext());
	assertEquals(b1, rs.nextBinding());
	assertTrue(rs.hasNext());
	assertEquals(b2, rs.nextBinding());
	assertFalse(rs.hasNext());
}
 

private void augmentQuery(final Query q, final List<Var> variables, final List<Binding> values) {
	if (variables.isEmpty()) {
		return;
	}
	ElementGroup old = (ElementGroup) q.getQueryPattern();
	ElementGroup newQueryPattern = new ElementGroup();
	q.setQueryPattern(newQueryPattern);
	if (old.size() >= 1 && old.get(0) instanceof ElementData) {
		ElementData qData = (ElementData) old.get(0);
		int oldSize = qData.getRows().size();
		qData = mergeValues(qData, variables, values);
		newQueryPattern.addElement(qData);
		for (int i = 1; i < old.size(); i++) {
			newQueryPattern.addElement(old.get(i));
		}
		LOG.debug("New query has " + qData.getRows().size() + " initial values. It had " + oldSize
				+ " values before");
	} else {
		ElementData data = new ElementData();
		variables.forEach(data::add);
		values.forEach(data::add);
		newQueryPattern.addElement(data);
		old.getElements().forEach(newQueryPattern::addElement);
		// unexplainable, but did happen
		check(data, values);
	}
}
 

private void check(ElementData data, Collection<Binding> values) {
	if (data.getRows().size() != values.size()) {
		LOG.warn("Different size for the values block here.\n Was " + values.size() + ": \n" + values + "\n now is "
				+ data.getRows().size() + ": \n" + data.getRows());
		StringBuilder sb = new StringBuilder(
				"Different size for the values block here.\n Was " + values.size() + ": \n" + values + "\n\n");
		int i = 0;
		for (Binding b : values) {
			sb.append("\nbinding ").append(i++).append(" is ").append(b);
		}
		LOG.warn(sb.toString());
	}
}
 

private static void addCompressedToElementData(ElementData el, Binding b) {
    final Binding compressed = compress(b);
    final Iterator<Var> varsIterator = compressed.vars();
    while (varsIterator.hasNext()) {
        el.add(varsIterator.next());
    }
    el.add(compressed);
}
 

@Override
public void visit(ElementData el) {
    LOG.warn("Should not reach this point");
}
 

@Override
public void visit(ElementData el) {
    LOG.warn("Should not reach this point");
}
 

@Override
public void visit(ElementData el) {
}
 

@Override
public void visit(ElementData el) {
    QuerySerializer.outputDataBlock(out, el.getVars(), el.getRows(), new SerializationContext(context.getPrologue()));
}
 

@Override
public void visit(ElementData e) {
	result = e;
	
}
 

@Override
public void visit(ElementData e) {
	result = e;
}
 

@Override
public void visit(ElementData ed) {
	vars.addAll(ed.getVars());
	
}
 

/**
 * Modifies a query so that it operates onto a table. This is achieved
 * by appending the table as a VALUES block to the end of the main
 * query pattern.
 * 
 * @param query Original query; will be modified in place
 * @param table Data table to be added into the query
 */
private void modifyQuery(Query query, final Table table) {
	ElementData tableElement = new ElementData() {
		@Override
		public Table getTable() {
			return table;
		}
	};
	for (Var var: table.getVars()) {
		// Skip ?ROWNUM for "SELECT *" queries -- see further below
		if (query.isSelectType() && query.isQueryResultStar() 
				&& var.equals(TarqlQuery.ROWNUM)) continue;
		tableElement.add(var);
	}
	ElementGroup groupElement = new ElementGroup();
	groupElement.addElement(tableElement);
	if (query.getQueryPattern() instanceof ElementGroup) {
		for (Element element: ((ElementGroup) query.getQueryPattern()).getElements()) {
			groupElement.addElement(element);
		}
	} else {
		groupElement.addElement(query.getQueryPattern());
	}
	query.setQueryPattern(groupElement);
	
	// For SELECT * queries, we don't want to include pseudo
	// columns such as ?ROWNUM that may exist in the table.
	// That's why we skipped ?ROWNUM further up.
	if (query.isSelectType() && query.isQueryResultStar()) {
		// Force expansion of "SELECT *" to actual projection list
		query.setResultVars();
		// Tell ARQ that it actually needs to pay attention to
		// the projection list
		query.setQueryResultStar(false);
		// And now we can add ?ROWNUM to the table, as the "*"
		// has already been expanded.
		tableElement.add(TarqlQuery.ROWNUM);
	}
	// Data can only be added to table after we've finished the
	// ?ROWNUM shenangians
	/*for (Binding binding: table.getRows()) {
		tableElement.add(binding);
	}*/
}