Examples with ContextItem org.exist.dom.persistent.ContextItem used on opensource projects

Example 1 with ContextItem

use of org.exist.dom.persistent.ContextItem in project exist by eXist-db.

the class Predicate method selectByPosition.

/**
 * @param outerSequence the outer sequence
 * @param contextSequence the context sequence
 * @param mode the mode
 * @param innerSeq the inner sequence
 *
 * @return The result of the positional evaluation of the predicate.
 *
 * @throws XPathException if an error occurs
 */
private Sequence selectByPosition(final Sequence outerSequence, final Sequence contextSequence, final int mode, final Sequence innerSeq) throws XPathException {
    if (outerSequence != null && !outerSequence.isEmpty() && Type.subTypeOf(contextSequence.getItemType(), Type.NODE) && contextSequence.isPersistentSet() && outerSequence.isPersistentSet()) {
        final Sequence result = new NewArrayNodeSet();
        final NodeSet contextSet = contextSequence.toNodeSet();
        switch(mode) {
            case Constants.CHILD_AXIS:
            case Constants.ATTRIBUTE_AXIS:
            case Constants.DESCENDANT_AXIS:
            case Constants.DESCENDANT_SELF_AXIS:
            case Constants.DESCENDANT_ATTRIBUTE_AXIS:
                {
                    final NodeSet outerNodeSet = outerSequence.toNodeSet();
                    // TODO: in some cases, especially with in-memory nodes,
                    // outerSequence.toNodeSet() will generate a document
                    // which will be different from the one(s) in contextSet
                    // ancestors will thus be empty :-(
                    // A special treatment of VirtualNodeSet does not seem to be
                    // required anymore
                    final Sequence ancestors = outerNodeSet.selectAncestors(contextSet, true, getExpressionId());
                    if (contextSet.getDocumentSet().intersection(outerNodeSet.getDocumentSet()).getDocumentCount() == 0) {
                        LOG.info("contextSet and outerNodeSet don't share any document");
                    }
                    final NewArrayNodeSet temp = new NewArrayNodeSet();
                    for (final SequenceIterator i = ancestors.iterate(); i.hasNext(); ) {
                        NodeProxy p = (NodeProxy) i.nextItem();
                        ContextItem contextNode = p.getContext();
                        temp.reset();
                        while (contextNode != null) {
                            if (contextNode.getContextId() == getExpressionId()) {
                                temp.add(contextNode.getNode());
                            }
                            contextNode = contextNode.getNextDirect();
                        }
                        p.clearContext(getExpressionId());
                        // TODO : understand why we sort here...
                        temp.sortInDocumentOrder();
                        for (final SequenceIterator j = innerSeq.iterate(); j.hasNext(); ) {
                            final NumericValue v = (NumericValue) j.nextItem();
                            // Non integers return... nothing, not even an error !
                            if (!v.hasFractionalPart() && !v.isZero()) {
                                // ... whereas we don't want a sorted array here
                                // TODO : rename this method as getInDocumentOrder ? -pb
                                p = temp.get(v.getInt() - 1);
                                if (p != null) {
                                    result.add(p);
                                }
                            // TODO : does null make sense here ? Well... sometimes ;-)
                            }
                        }
                    }
                    break;
                }
            default:
                for (final SequenceIterator i = outerSequence.iterate(); i.hasNext(); ) {
                    NodeProxy p = (NodeProxy) i.nextItem();
                    Sequence temp;
                    boolean reverseAxis = true;
                    switch(mode) {
                        case Constants.ANCESTOR_AXIS:
                            temp = contextSet.selectAncestors(p, false, Expression.IGNORE_CONTEXT);
                            break;
                        case Constants.ANCESTOR_SELF_AXIS:
                            temp = contextSet.selectAncestors(p, true, Expression.IGNORE_CONTEXT);
                            break;
                        case Constants.PARENT_AXIS:
                            // TODO : understand why the contextSet is not involved
                            // here
                            // NodeProxy.getParent returns a *theoretical* parent
                            // which is *not* guaranteed to be in the context set !
                            temp = p.getParents(Expression.NO_CONTEXT_ID);
                            break;
                        case Constants.PRECEDING_AXIS:
                            temp = contextSet.selectPreceding(p, Expression.IGNORE_CONTEXT);
                            break;
                        case Constants.PRECEDING_SIBLING_AXIS:
                            temp = contextSet.selectPrecedingSiblings(p, Expression.IGNORE_CONTEXT);
                            break;
                        case Constants.FOLLOWING_SIBLING_AXIS:
                            temp = contextSet.selectFollowingSiblings(p, Expression.IGNORE_CONTEXT);
                            reverseAxis = false;
                            break;
                        case Constants.FOLLOWING_AXIS:
                            temp = contextSet.selectFollowing(p, Expression.IGNORE_CONTEXT);
                            reverseAxis = false;
                            break;
                        case Constants.SELF_AXIS:
                            temp = p;
                            reverseAxis = false;
                            break;
                        default:
                            throw new IllegalArgumentException("Tried to test unknown axis");
                    }
                    if (!temp.isEmpty()) {
                        for (final SequenceIterator j = innerSeq.iterate(); j.hasNext(); ) {
                            final NumericValue v = (NumericValue) j.nextItem();
                            // Non integers return... nothing, not even an error !
                            if (!v.hasFractionalPart() && !v.isZero()) {
                                final int pos = (reverseAxis ? temp.getItemCount() - v.getInt() : v.getInt() - 1);
                                // Other positions are ignored
                                if (pos >= 0 && pos < temp.getItemCount()) {
                                    final NodeProxy t = (NodeProxy) temp.itemAt(pos);
                                    // for the current context: filter out those
                                    // context items not selected by the positional predicate
                                    ContextItem ctx = t.getContext();
                                    t.clearContext(Expression.IGNORE_CONTEXT);
                                    while (ctx != null) {
                                        if (ctx.getContextId() == outerContextId) {
                                            if (ctx.getNode().getNodeId().equals(p.getNodeId())) {
                                                t.addContextNode(outerContextId, ctx.getNode());
                                            }
                                        } else {
                                            t.addContextNode(ctx.getContextId(), ctx.getNode());
                                        }
                                        ctx = ctx.getNextDirect();
                                    }
                                    result.add(t);
                                }
                            }
                        }
                    }
                }
        }
        return result;
    } else {
        final boolean reverseAxis = Type.subTypeOf(contextSequence.getItemType(), Type.NODE) && (mode == Constants.ANCESTOR_AXIS || mode == Constants.ANCESTOR_SELF_AXIS || mode == Constants.PARENT_AXIS || mode == Constants.PRECEDING_AXIS || mode == Constants.PRECEDING_SIBLING_AXIS);
        final Set<NumericValue> set = new TreeSet<>();
        final ValueSequence result = new ValueSequence();
        for (final SequenceIterator i = innerSeq.iterate(); i.hasNext(); ) {
            final NumericValue v = (NumericValue) i.nextItem();
            // Non integers return... nothing, not even an error !
            if (!v.hasFractionalPart() && !v.isZero()) {
                final int pos = (reverseAxis ? contextSequence.getItemCount() - v.getInt() : v.getInt() - 1);
                // Other positions are ignored
                if (pos >= 0 && pos < contextSequence.getItemCount() && !set.contains(v)) {
                    result.add(contextSequence.itemAt(pos));
                    set.add(v);
                }
            }
        }
        return result;
    }
}

Example 2 with ContextItem

use of org.exist.dom.persistent.ContextItem in project exist by eXist-db.

the class ValueComparison method nodeSetCompare.

protected Sequence nodeSetCompare(NodeSet nodes, Sequence contextSequence) throws XPathException {
    if (context.getProfiler().isEnabled()) {
        context.getProfiler().message(this, Profiler.OPTIMIZATION_FLAGS, "OPTIMIZATION CHOICE", "nodeSetCompare");
    }
    final NodeSet result = new ExtArrayNodeSet();
    final Collator collator = getCollator(contextSequence);
    if (contextSequence != null && !contextSequence.isEmpty()) {
        for (final NodeProxy current : nodes) {
            ContextItem context = current.getContext();
            if (context == null) {
                throw new XPathException(this, ErrorCodes.XPDY0002, "Context is missing for node set comparison");
            }
            do {
                final AtomicValue lv = current.atomize();
                final Sequence rs = getRight().eval(context.getNode().toSequence());
                if (!rs.hasOne()) {
                    throw new XPathException(this, ErrorCodes.XPTY0004, "Type error: sequence with less or more than one item is not allowed here");
                }
                if (compareAtomic(collator, lv, rs.itemAt(0).atomize(), StringTruncationOperator.NONE, relation)) {
                    result.add(current);
                }
            } while ((context = context.getNextDirect()) != null);
        }
    } else {
        final Sequence rs = getRight().eval(null);
        if (!rs.hasOne()) {
            throw new XPathException(this, ErrorCodes.XPTY0004, "Type error: sequence with less or more than one item is not allowed here");
        }
        final AtomicValue rv = rs.itemAt(0).atomize();
        for (final NodeProxy current : nodes) {
            final AtomicValue lv = current.atomize();
            if (compareAtomic(collator, lv, rv, StringTruncationOperator.NONE, Comparison.EQ)) {
                result.add(current);
            }
        }
    }
    return result;
}

Example 3 with ContextItem

use of org.exist.dom.persistent.ContextItem in project exist by eXist-db.

the class PreorderedValueSequence method processAll.

private void processAll() throws XPathException {
    for (int i = 0; i < orderSpecs.length; i++) {
        final Expression expr = orderSpecs[i].getSortExpression();
        final NodeSet result = expr.eval(null).toNodeSet();
        for (final NodeProxy p : result) {
            ContextItem context = p.getContext();
            // TODO : review to consider transverse context
            while (context != null) {
                if (context.getNode() instanceof OrderedNodeProxy) {
                    final OrderedNodeProxy cp = (OrderedNodeProxy) context.getNode();
                    cp.values[i] = p.atomize();
                }
                context = context.getNextDirect();
            }
        }
    }
}

Example 4 with ContextItem

use of org.exist.dom.persistent.ContextItem in project exist by eXist-db.

the class Predicate method selectByNodeSet.

/**
 * @param contextSequence the context sequence
 *
 * @return The result of the node set evaluation of the predicate.
 *
 * @throws XPathException if an error occurs
 */
private Sequence selectByNodeSet(final Sequence contextSequence) throws XPathException {
    final NewArrayNodeSet result = new NewArrayNodeSet();
    final NodeSet contextSet = contextSequence.toNodeSet();
    final boolean contextIsVirtual = contextSet instanceof VirtualNodeSet;
    contextSet.setTrackMatches(false);
    final NodeSet nodes = super.eval(contextSet, null).toNodeSet();
    /*
         * if the predicate expression returns results from the cache we can
         * also return the cached result.
         */
    if (cached != null && cached.isValid(contextSequence, null) && nodes.isCached()) {
        if (context.getProfiler().isEnabled()) {
            context.getProfiler().message(this, Profiler.OPTIMIZATIONS, "Using cached results", result);
        }
        return cached.getResult();
    }
    DocumentImpl lastDoc = null;
    for (final NodeProxy currentNode : nodes) {
        int sizeHint = Constants.NO_SIZE_HINT;
        if (lastDoc == null || currentNode.getOwnerDocument() != lastDoc) {
            lastDoc = currentNode.getOwnerDocument();
            sizeHint = nodes.getSizeHint(lastDoc);
        }
        ContextItem contextItem = currentNode.getContext();
        if (contextItem == null) {
            throw new XPathException(this, "Internal evaluation error: context is missing for node " + currentNode.getNodeId() + " !");
        }
        // TODO : review to consider transverse context
        while (contextItem != null) {
            if (contextItem.getContextId() == getExpressionId()) {
                final NodeProxy next = contextItem.getNode();
                if (contextIsVirtual || contextSet.contains(next)) {
                    next.addMatches(currentNode);
                    result.add(next, sizeHint);
                }
            }
            contextItem = contextItem.getNextDirect();
        }
    }
    if (contextSequence.isCacheable()) {
        cached = new CachedResult(contextSequence, null, result);
    }
    contextSet.setTrackMatches(true);
    return result;
}

Example 5 with ContextItem

use of org.exist.dom.persistent.ContextItem in project exist by eXist-db.

the class GeneralComparison method nodeSetCompare.

/**
 * Optimized implementation, which can be applied if the left operand returns a node set. In this case, the left expression is executed first. All
 * matching context nodes are then passed to the right expression.
 *
 * @param   nodes            DOCUMENT ME!
 * @param   contextSequence  DOCUMENT ME!
 *
 * @return  DOCUMENT ME!
 *
 * @throws  XPathException  DOCUMENT ME!
 */
protected Sequence nodeSetCompare(NodeSet nodes, Sequence contextSequence) throws XPathException {
    if (context.getProfiler().isEnabled()) {
        context.getProfiler().message(this, Profiler.OPTIMIZATION_FLAGS, "OPTIMIZATION CHOICE", "nodeSetCompare");
    }
    if (LOG.isTraceEnabled()) {
        LOG.trace("No index: fall back to nodeSetCompare");
    }
    final long start = System.currentTimeMillis();
    final NodeSet result = new NewArrayNodeSet();
    final Collator collator = getCollator(contextSequence);
    if ((contextSequence != null) && !contextSequence.isEmpty() && !contextSequence.getDocumentSet().contains(nodes.getDocumentSet())) {
        for (final NodeProxy item : nodes) {
            ContextItem context = item.getContext();
            if (context == null) {
                throw (new XPathException(this, "Internal error: context node missing"));
            }
            final AtomicValue lv = item.atomize();
            do {
                final Sequence rs = getRight().eval(context.getNode().toSequence());
                for (final SequenceIterator i2 = Atomize.atomize(rs).iterate(); i2.hasNext(); ) {
                    final AtomicValue rv = i2.nextItem().atomize();
                    if (compareAtomic(collator, lv, rv)) {
                        result.add(item);
                    }
                }
            } while ((context = context.getNextDirect()) != null);
        }
    } else {
        for (final NodeProxy item : nodes) {
            final AtomicValue lv = item.atomize();
            final Sequence rs = getRight().eval(contextSequence);
            for (final SequenceIterator i2 = Atomize.atomize(rs).iterate(); i2.hasNext(); ) {
                final AtomicValue rv = i2.nextItem().atomize();
                if (compareAtomic(collator, lv, rv)) {
                    result.add(item);
                }
            }
        }
    }
    if (context.getProfiler().traceFunctions()) {
        context.getProfiler().traceIndexUsage(context, PerformanceStats.RANGE_IDX_TYPE, this, PerformanceStats.NO_INDEX, System.currentTimeMillis() - start);
    }
    return (result);
}