Examples with Pair org.apache.jena.atlas.lib.Pair used on opensource projects

Example 1 with Pair

use of org.apache.jena.atlas.lib.Pair in project jena by apache.

the class NodeTableTrans method append.

/** Copy from the journal file to the real file */
/*package*/
void append() {
    Iterator<Pair<NodeId, Node>> iter = nodeTableJournal.all();
    Pair<NodeId, Node> firstPair = null;
    Pair<NodeId, Node> lastPair = null;
    for (; iter.hasNext(); ) {
        Pair<NodeId, Node> x = iter.next();
        if (firstPair == null)
            firstPair = x;
        lastPair = x;
        NodeId nodeId = x.getLeft();
        Node node = x.getRight();
        debug("  append: %s -> %s", x, mapFromJournal(nodeId));
        // This does the write.
        NodeId nodeId2 = base.getAllocateNodeId(node);
        if (!nodeId2.equals(mapFromJournal(nodeId)))
            inconsistent(node, nodeId, nodeId2);
    }
}

Example 2 with Pair

use of org.apache.jena.atlas.lib.Pair in project jena by apache.

the class TransformFilterEquality method preprocessFilterEquality.

// --- find and extract
private static Pair<List<Pair<Var, NodeValue>>, ExprList> preprocessFilterEquality(ExprList exprs) {
    List<Pair<Var, NodeValue>> exprsFilterEquality = new ArrayList<>();
    ExprList exprsOther = new ExprList();
    for (Expr e : exprs.getList()) {
        Pair<Var, NodeValue> p = preprocess(e);
        if (p != null)
            exprsFilterEquality.add(p);
        else
            exprsOther.add(e);
    }
    if (exprsFilterEquality.size() == 0)
        return null;
    return Pair.create(exprsFilterEquality, exprsOther);
}

Example 3 with Pair

use of org.apache.jena.atlas.lib.Pair in project jena by apache.

the class TransformFilterInequality method apply.

private static Op apply(ExprList exprs, Op subOp) {
    // ---- Find and extract any inequality filters.
    Pair<List<Pair<Var, NodeValue>>, ExprList> p = preprocessFilterInequality(exprs);
    if (p == null || p.getLeft().size() == 0)
        return null;
    List<Pair<Var, NodeValue>> inequalities = p.getLeft();
    Collection<Var> varsMentioned = varsMentionedInInequalityFilters(inequalities);
    ExprList remaining = p.getRight();
    // If any of the conditions overlap the optimization is unsafe
    // (the query is also likely incorrect but that isn't our problem)
    // TODO There is actually a special case here, if the inequality
    // constraints are conflicting then we can special case to table empty.
    // ---- Check if the subOp is the right shape to transform.
    Op op = subOp;
    // hence eliminate all rows. Return the empty table.
    if (testSpecialCaseUnused(subOp, inequalities, remaining))
        return OpTable.empty();
    // { OPTIONAL{P1} OPTIONAL{P2} ... FILTER(?x = :x) }
    if (testSpecialCase1(subOp, inequalities, remaining)) {
        // Find backbone of ops
        List<Op> ops = extractOptionals(subOp);
        ops = processSpecialCase1(ops, inequalities);
        // Put back together
        op = rebuild((Op2) subOp, ops);
        // Put all filters - either we optimized, or we left alone.
        // Either way, the complete set of filter expressions.
        op = OpFilter.filterBy(exprs, op);
        return op;
    }
    if (!safeToTransform(varsMentioned, op))
        return null;
    op = processFilterWorker(op, inequalities);
    // ---- Place any filter expressions around the processed sub op.
    if (remaining.size() > 0)
        op = OpFilter.filterBy(remaining, op);
    return op;
}

Example 4 with Pair

use of org.apache.jena.atlas.lib.Pair in project jena by apache.

the class NodeTableLib method print.

public static void print(String label, NodeTable nodeTable) {
    if (label != null)
        System.out.println(label);
    Iterator<Pair<NodeId, Node>> iter = nodeTable.all();
    for (; iter.hasNext(); ) {
        Pair<NodeId, Node> x = iter.next();
        NodeId nodeId = x.getLeft();
        Node node = x.getRight();
        System.out.println(nodeId + " " + node);
    }
}

Example 5 with Pair

use of org.apache.jena.atlas.lib.Pair in project jena by apache.

the class QueryIterGroup method calc.

private static Iterator<Binding> calc(final QueryIterator iter, final VarExprList groupVarExpr, final List<ExprAggregator> aggregators, final ExecutionContext execCxt) {
    return new IteratorDelayedInitialization<Binding>() {

        @Override
        protected Iterator<Binding> initializeIterator() {
            boolean noAggregators = (aggregators == null || aggregators.isEmpty());
            // Phase 1 : assign bindings to buckets by key and pump through the aggregators.
            Multimap<Binding, Pair<Var, Accumulator>> accumulators = HashMultimap.create();
            while (iter.hasNext()) {
                Binding b = iter.nextBinding();
                Binding key = genKey(groupVarExpr, b, execCxt);
                if (noAggregators) {
                    // Put in a dummy to remember the input.
                    accumulators.put(key, placeholder);
                    continue;
                }
                // Create if does not exist.
                if (!accumulators.containsKey(key)) {
                    for (ExprAggregator agg : aggregators) {
                        Accumulator x = agg.getAggregator().createAccumulator();
                        Var v = agg.getVar();
                        accumulators.put(key, Pair.create(v, x));
                    }
                }
                // Do the per-accumulator calculation.
                for (Pair<Var, Accumulator> pair : accumulators.get(key)) pair.getRight().accumulate(b, execCxt);
            }
            if (accumulators.isEmpty()) {
                if (noAggregators) {
                    // ==> No result rows.
                    return Iter.nullIterator();
                }
                BindingMap binding = BindingFactory.create();
                for (ExprAggregator agg : aggregators) {
                    Var v = agg.getVar();
                    Node value = agg.getAggregator().getValueEmpty();
                    if (value != null) {
                        binding.add(v, value);
                    }
                }
                if (binding == null)
                    // This does not happen if there are any aggregators. 
                    return Iter.nullIterator();
                // cast to get the static type inference to work.
                return Iter.singletonIter((Binding) binding);
            }
            if (noAggregators)
                // We used placeholder so there are always the key. 
                return accumulators.keySet().iterator();
            List<Binding> results = new ArrayList<>();
            for (Binding k : accumulators.keySet()) {
                Collection<Pair<Var, Accumulator>> accs = accumulators.get(k);
                BindingMap b = BindingFactory.create(k);
                for (Pair<Var, Accumulator> pair : accs) {
                    Var v = pair.getLeft();
                    NodeValue value = pair.getRight().getValue();
                    Node n = (value == null) ? null : value.asNode();
                    if (v == null || n == null) {
                    } else
                        b.add(v, n);
                }
                results.add(b);
            }
            return results.iterator();
        }
    };
}