2 * Copyright (c) 2020 PANTHEON.tech, s.r.o. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.yangtools.yang.model.util;
10 import static com.google.common.base.Preconditions.checkArgument;
11 import static com.google.common.base.Preconditions.checkState;
12 import static com.google.common.base.Verify.verify;
13 import static com.google.common.base.Verify.verifyNotNull;
14 import static java.util.Objects.requireNonNull;
16 import com.google.common.annotations.Beta;
17 import com.google.common.base.MoreObjects;
18 import com.google.common.base.VerifyException;
19 import com.google.common.collect.ImmutableList;
20 import com.google.common.collect.Iterators;
21 import java.util.ArrayDeque;
22 import java.util.Deque;
23 import java.util.Iterator;
24 import java.util.List;
25 import java.util.NoSuchElementException;
26 import java.util.Optional;
27 import org.eclipse.jdt.annotation.NonNull;
28 import org.eclipse.jdt.annotation.Nullable;
29 import org.opendaylight.yangtools.concepts.Mutable;
30 import org.opendaylight.yangtools.yang.common.AbstractQName;
31 import org.opendaylight.yangtools.yang.common.QName;
32 import org.opendaylight.yangtools.yang.common.QNameModule;
33 import org.opendaylight.yangtools.yang.common.UnqualifiedQName;
34 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
35 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContextProvider;
36 import org.opendaylight.yangtools.yang.model.api.EffectiveStatementInference;
37 import org.opendaylight.yangtools.yang.model.api.LeafSchemaNode;
38 import org.opendaylight.yangtools.yang.model.api.PathExpression;
39 import org.opendaylight.yangtools.yang.model.api.PathExpression.DerefSteps;
40 import org.opendaylight.yangtools.yang.model.api.PathExpression.LocationPathSteps;
41 import org.opendaylight.yangtools.yang.model.api.PathExpression.Steps;
42 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
43 import org.opendaylight.yangtools.yang.model.api.SchemaTreeInference;
44 import org.opendaylight.yangtools.yang.model.api.TypeAware;
45 import org.opendaylight.yangtools.yang.model.api.TypeDefinition;
46 import org.opendaylight.yangtools.yang.model.api.TypedDataSchemaNode;
47 import org.opendaylight.yangtools.yang.model.api.meta.EffectiveStatement;
48 import org.opendaylight.yangtools.yang.model.api.stmt.CaseEffectiveStatement;
49 import org.opendaylight.yangtools.yang.model.api.stmt.ChoiceEffectiveStatement;
50 import org.opendaylight.yangtools.yang.model.api.stmt.DataTreeAwareEffectiveStatement;
51 import org.opendaylight.yangtools.yang.model.api.stmt.DataTreeEffectiveStatement;
52 import org.opendaylight.yangtools.yang.model.api.stmt.GroupingEffectiveStatement;
53 import org.opendaylight.yangtools.yang.model.api.stmt.ModuleEffectiveStatement;
54 import org.opendaylight.yangtools.yang.model.api.stmt.SchemaNodeIdentifier;
55 import org.opendaylight.yangtools.yang.model.api.stmt.SchemaNodeIdentifier.Absolute;
56 import org.opendaylight.yangtools.yang.model.api.stmt.SchemaTreeAwareEffectiveStatement;
57 import org.opendaylight.yangtools.yang.model.api.stmt.SchemaTreeEffectiveStatement;
58 import org.opendaylight.yangtools.yang.model.api.stmt.TypedefEffectiveStatement;
59 import org.opendaylight.yangtools.yang.model.api.type.InstanceIdentifierTypeDefinition;
60 import org.opendaylight.yangtools.yang.model.api.type.LeafrefTypeDefinition;
61 import org.opendaylight.yangtools.yang.model.spi.AbstractEffectiveStatementInference;
62 import org.opendaylight.yangtools.yang.model.spi.DefaultSchemaTreeInference;
63 import org.opendaylight.yangtools.yang.xpath.api.YangLocationPath;
64 import org.opendaylight.yangtools.yang.xpath.api.YangLocationPath.AxisStep;
65 import org.opendaylight.yangtools.yang.xpath.api.YangLocationPath.QNameStep;
66 import org.opendaylight.yangtools.yang.xpath.api.YangLocationPath.Step;
67 import org.opendaylight.yangtools.yang.xpath.api.YangXPathAxis;
70 * A state tracking utility for walking {@link EffectiveModelContext}'s contents along schema/grouping namespaces. This
71 * is conceptually a stack, tracking {@link EffectiveStatement}s encountered along traversal.
74 * This is meant to be a replacement concept for the use of {@link SchemaPath} in various places, notably
75 * in {@link SchemaContextUtil} methods.
78 * This class is designed for single-threaded uses and does not make any guarantees around concurrent access.
81 public final class SchemaInferenceStack implements Mutable, EffectiveModelContextProvider, LeafrefResolver {
83 * Semantic binding of {@link EffectiveStatementInference} produced by {@link SchemaInferenceStack}. Sequence of
84 * {@link #statementPath()} is implementation-specific.
87 public static final class Inference extends AbstractEffectiveStatementInference<EffectiveStatement<?, ?>> {
88 private final ArrayDeque<EffectiveStatement<?, ?>> deque;
89 private final ModuleEffectiveStatement currentModule;
90 private final int groupingDepth;
91 private final boolean clean;
93 Inference(final @NonNull EffectiveModelContext modelContext, final ArrayDeque<EffectiveStatement<?, ?>> deque,
94 final ModuleEffectiveStatement currentModule, final int groupingDepth, final boolean clean) {
96 this.deque = requireNonNull(deque);
97 this.currentModule = currentModule;
98 this.groupingDepth = groupingDepth;
103 * Create a new stack backed by an effective model and set up to point and specified data tree node.
105 * @param effectiveModel EffectiveModelContext to which this stack is attached
106 * @param qnames Data tree path qnames
107 * @return A new stack
108 * @throws NullPointerException if any argument is null or path contains a null element
109 * @throws IllegalArgumentException if a path element cannot be found
111 public static @NonNull Inference ofDataTreePath(final EffectiveModelContext effectiveModel,
112 final QName... qnames) {
113 return SchemaInferenceStack.ofDataTreePath(effectiveModel, qnames).toInference();
117 public List<EffectiveStatement<?, ?>> statementPath() {
118 return ImmutableList.copyOf(deque.descendingIterator());
122 * Convert this inference into a {@link SchemaInferenceStack}.
124 * @return A new stack
126 public @NonNull SchemaInferenceStack toSchemaInferenceStack() {
127 return new SchemaInferenceStack(getEffectiveModelContext(), deque, currentModule, groupingDepth, clean);
131 private final @NonNull EffectiveModelContext effectiveModel;
132 private final ArrayDeque<EffectiveStatement<?, ?>> deque;
134 private @Nullable ModuleEffectiveStatement currentModule;
135 private int groupingDepth;
137 // True if there were only steps along grouping and schema tree, hence it is consistent with SchemaNodeIdentifier
138 // False if we have evidence of a data tree lookup succeeding
139 private boolean clean;
141 private SchemaInferenceStack(final EffectiveModelContext effectiveModel, final int expectedSize) {
142 this.deque = new ArrayDeque<>(expectedSize);
143 this.effectiveModel = requireNonNull(effectiveModel);
147 private SchemaInferenceStack(final SchemaInferenceStack source) {
148 this.deque = source.deque.clone();
149 this.effectiveModel = source.effectiveModel;
150 this.currentModule = source.currentModule;
151 this.groupingDepth = source.groupingDepth;
152 this.clean = source.clean;
155 private SchemaInferenceStack(final EffectiveModelContext effectiveModel,
156 final ArrayDeque<EffectiveStatement<?, ?>> deque, final ModuleEffectiveStatement currentModule,
157 final int groupingDepth, final boolean clean) {
158 this.effectiveModel = requireNonNull(effectiveModel);
159 this.deque = deque.clone();
160 this.currentModule = currentModule;
161 this.groupingDepth = groupingDepth;
165 private SchemaInferenceStack(final EffectiveModelContext effectiveModel) {
166 this.effectiveModel = requireNonNull(effectiveModel);
167 this.deque = new ArrayDeque<>();
172 * Create a new empty stack backed by an effective model.
174 * @param effectiveModel EffectiveModelContext to which this stack is attached
175 * @return A new stack
176 * @throws NullPointerException if {@code effectiveModel} is null
178 public static @NonNull SchemaInferenceStack of(final EffectiveModelContext effectiveModel) {
179 return new SchemaInferenceStack(effectiveModel);
183 * Create a new stack backed by an effective model, pointing to specified schema node identified by
186 * @param effectiveModel EffectiveModelContext to which this stack is attached
187 * @return A new stack
188 * @throws NullPointerException if {@code effectiveModel} is null
189 * @throws IllegalArgumentException if {@code path} cannot be resolved in the effective model
191 public static @NonNull SchemaInferenceStack of(final EffectiveModelContext effectiveModel, final Absolute path) {
192 final SchemaInferenceStack ret = new SchemaInferenceStack(effectiveModel);
193 path.getNodeIdentifiers().forEach(ret::enterSchemaTree);
198 * Create a new stack from an {@link EffectiveStatementInference}.
200 * @param inference Inference to use for initialization
201 * @return A new stack
202 * @throws NullPointerException if {@code inference} is null
203 * @throws IllegalArgumentException if {@code inference} implementation is not supported
205 public static @NonNull SchemaInferenceStack ofInference(final EffectiveStatementInference inference) {
206 if (inference.statementPath().isEmpty()) {
207 return new SchemaInferenceStack(inference.getEffectiveModelContext());
208 } else if (inference instanceof SchemaTreeInference) {
209 return ofInference((SchemaTreeInference) inference);
210 } else if (inference instanceof Inference) {
211 return ((Inference) inference).toSchemaInferenceStack();
213 throw new IllegalArgumentException("Unsupported Inference " + inference);
218 * Create a new stack from an {@link SchemaTreeInference}.
220 * @param inference SchemaTreeInference to use for initialization
221 * @return A new stack
222 * @throws NullPointerException if {@code inference} is null
223 * @throws IllegalArgumentException if {@code inference} cannot be resolved to a valid stack
225 public static @NonNull SchemaInferenceStack ofInference(final SchemaTreeInference inference) {
226 return of(inference.getEffectiveModelContext(), inference.toSchemaNodeIdentifier());
230 * Create a new stack backed by an effective model and set up to point and specified data tree node.
232 * @param effectiveModel EffectiveModelContext to which this stack is attached
233 * @return A new stack
234 * @throws NullPointerException if any argument is null or path contains a null element
235 * @throws IllegalArgumentException if a path element cannot be found
237 public static @NonNull SchemaInferenceStack ofDataTreePath(final EffectiveModelContext effectiveModel,
238 final QName... path) {
239 final SchemaInferenceStack ret = new SchemaInferenceStack(effectiveModel);
240 for (QName qname : path) {
241 ret.enterDataTree(qname);
247 * Create a new stack backed by an effective model, pointing to specified schema node identified by an absolute
248 * {@link SchemaPath} and its {@link SchemaPath#getPathFromRoot()} interpreted as a schema node identifier.
250 * @param effectiveModel EffectiveModelContext to which this stack is attached
251 * @return A new stack
252 * @throws NullPointerException {@code effectiveModel} is null
253 * @throws IllegalArgumentException if {@code path} cannot be resolved in the effective model or if it is not an
257 public static @NonNull SchemaInferenceStack ofInstantiatedPath(final EffectiveModelContext effectiveModel,
258 final SchemaPath path) {
259 checkArgument(path.isAbsolute(), "Cannot operate on relative path %s", path);
260 final SchemaInferenceStack ret = new SchemaInferenceStack(effectiveModel);
261 path.getPathFromRoot().forEach(ret::enterSchemaTree);
266 * Create a new stack backed by an effective model, pointing to specified schema node identified by an absolute
267 * {@link SchemaPath} and its {@link SchemaPath#getPathFromRoot()}, interpreted as a series of steps along primarily
268 * schema tree, with grouping namespace being the alternative lookup.
270 * @param effectiveModel EffectiveModelContext to which this stack is attached
271 * @return A new stack
272 * @throws NullPointerException {@code effectiveModel} is null
273 * @throws IllegalArgumentException if {@code path} cannot be resolved in the effective model or if it is not an
277 public static @NonNull SchemaInferenceStack ofSchemaPath(final EffectiveModelContext effectiveModel,
278 final SchemaPath path) {
279 checkArgument(path.isAbsolute(), "Cannot operate on relative path %s", path);
280 final SchemaInferenceStack ret = new SchemaInferenceStack(effectiveModel);
282 for (QName step : path.getPathFromRoot()) {
284 ret.enterSchemaTree(step);
285 } catch (IllegalArgumentException schemaEx) {
287 ret.enterGrouping(step);
288 } catch (IllegalArgumentException ex) {
289 ex.addSuppressed(schemaEx);
299 public EffectiveModelContext getEffectiveModelContext() {
300 return effectiveModel;
304 * Create a deep copy of this object.
306 * @return An isolated copy of this object
308 public @NonNull SchemaInferenceStack copy() {
309 return new SchemaInferenceStack(this);
313 * Check if this stack is empty.
315 * @return True if this stack has not entered any node.
317 public boolean isEmpty() {
318 return deque.isEmpty();
322 * Return the statement at the top of the stack.
324 * @return Top statement
325 * @throws IllegalStateException if the stack is empty
327 public @NonNull EffectiveStatement<?, ?> currentStatement() {
328 return checkNonNullState(deque.peekFirst());
332 * Return current module the stack has entered.
334 * @return Current module
335 * @throws IllegalStateException if the stack is empty
337 public @NonNull ModuleEffectiveStatement currentModule() {
338 return checkNonNullState(currentModule);
342 * Check if the stack is in instantiated context. This indicates the stack is non-empty and there are only screma
343 * tree statements in the stack.
345 * @return False if the stack is empty or contains a statement which is not a {@link SchemaTreeEffectiveStatement},
348 public boolean inInstantiatedContext() {
349 return groupingDepth == 0 && !deque.isEmpty()
350 && deque.stream().allMatch(SchemaTreeEffectiveStatement.class::isInstance);
354 * Check if the stack is in a {@code grouping} context.
356 * @return False if the stack contains a grouping.
358 public boolean inGrouping() {
359 return groupingDepth != 0;
363 * Reset this stack to empty state.
365 public void clear() {
367 currentModule = null;
373 * Lookup a {@code choice} by its node identifier and push it to the stack. This step is very similar to
374 * {@link #enterSchemaTree(QName)}, except it handles the use case where traversal ignores actual {@code case}
375 * intermediate schema tree children.
377 * @param nodeIdentifier Node identifier of the choice to enter
378 * @return Resolved choice
379 * @throws NullPointerException if {@code nodeIdentifier} is null
380 * @throws IllegalArgumentException if the corresponding choice cannot be found
382 public @NonNull ChoiceEffectiveStatement enterChoice(final QName nodeIdentifier) {
383 final EffectiveStatement<?, ?> parent = deque.peek();
384 if (parent instanceof ChoiceEffectiveStatement) {
385 return enterChoice((ChoiceEffectiveStatement) parent, nodeIdentifier);
388 // Fall back to schema tree lookup. Note if it results in non-choice, we rewind before reporting an error
389 final SchemaTreeEffectiveStatement<?> result = enterSchemaTree(nodeIdentifier);
390 if (result instanceof ChoiceEffectiveStatement) {
391 return (ChoiceEffectiveStatement) result;
394 throw new IllegalArgumentException("Choice " + nodeIdentifier + " not present");
397 // choice -> choice transition, we have to deal with intermediate case nodes
398 private @NonNull ChoiceEffectiveStatement enterChoice(final ChoiceEffectiveStatement parent,
399 final QName nodeIdentifier) {
400 for (EffectiveStatement<?, ?> stmt : parent.effectiveSubstatements()) {
401 if (stmt instanceof CaseEffectiveStatement) {
402 final Optional<ChoiceEffectiveStatement> optMatch = ((CaseEffectiveStatement) stmt)
403 .findSchemaTreeNode(nodeIdentifier)
404 .filter(ChoiceEffectiveStatement.class::isInstance)
405 .map(ChoiceEffectiveStatement.class::cast);
406 if (optMatch.isPresent()) {
407 final SchemaTreeEffectiveStatement<?> match = optMatch.orElseThrow();
410 return (ChoiceEffectiveStatement) match;
414 throw new IllegalArgumentException("Choice " + nodeIdentifier + " not present");
418 * Lookup a {@code grouping} by its node identifier and push it to the stack.
420 * @param nodeIdentifier Node identifier of the grouping to enter
421 * @return Resolved grouping
422 * @throws NullPointerException if {@code nodeIdentifier} is null
423 * @throws IllegalArgumentException if the corresponding grouping cannot be found
425 public @NonNull GroupingEffectiveStatement enterGrouping(final QName nodeIdentifier) {
426 return pushGrouping(requireNonNull(nodeIdentifier));
430 * Lookup a {@code schema tree} child by its node identifier and push it to the stack.
432 * @param nodeIdentifier Node identifier of the schema tree child to enter
433 * @return Resolved schema tree child
434 * @throws NullPointerException if {@code nodeIdentifier} is null
435 * @throws IllegalArgumentException if the corresponding child cannot be found
437 public @NonNull SchemaTreeEffectiveStatement<?> enterSchemaTree(final QName nodeIdentifier) {
438 return pushSchema(requireNonNull(nodeIdentifier));
442 * Lookup a {@code schema tree} node by its schema node identifier and push it to the stack.
444 * @param nodeIdentifier Schema node identifier of the schema tree node to enter
445 * @return Resolved schema tree node
446 * @throws NullPointerException if {@code nodeIdentifier} is null
447 * @throws IllegalArgumentException if the corresponding node cannot be found
449 public @NonNull SchemaTreeEffectiveStatement<?> enterSchemaTree(final SchemaNodeIdentifier nodeIdentifier) {
450 if (nodeIdentifier instanceof Absolute) {
454 final Iterator<QName> it = nodeIdentifier.getNodeIdentifiers().iterator();
455 SchemaTreeEffectiveStatement<?> ret;
457 ret = enterSchemaTree(it.next());
458 } while (it.hasNext());
464 * Lookup a {@code schema tree} child by its node identifier and push it to the stack.
466 * @param nodeIdentifier Node identifier of the date tree child to enter
467 * @return Resolved date tree child
468 * @throws NullPointerException if {@code nodeIdentifier} is null
469 * @throws IllegalArgumentException if the corresponding child cannot be found
471 public @NonNull DataTreeEffectiveStatement<?> enterDataTree(final QName nodeIdentifier) {
472 return pushData(requireNonNull(nodeIdentifier));
476 * Lookup a {@code typedef} by its node identifier and push it to the stack.
478 * @param nodeIdentifier Node identifier of the typedef to enter
479 * @return Resolved typedef
480 * @throws NullPointerException if {@code nodeIdentifier} is null
481 * @throws IllegalArgumentException if the corresponding typedef cannot be found
483 public @NonNull TypedefEffectiveStatement enterTypedef(final QName nodeIdentifier) {
484 return pushTypedef(requireNonNull(nodeIdentifier));
488 * Pop the current statement from the stack.
490 * @return Previous statement
491 * @throws NoSuchElementException if this stack is empty
493 public @NonNull EffectiveStatement<?, ?> exit() {
494 final EffectiveStatement<?, ?> prev = deque.pop();
495 if (prev instanceof GroupingEffectiveStatement) {
498 if (deque.isEmpty()) {
499 currentModule = null;
506 * Pop the current statement from the stack, asserting it is a {@link DataTreeEffectiveStatement} and that
507 * subsequent {@link #enterDataTree(QName)} will find it again.
509 * @return Previous statement
510 * @throws NoSuchElementException if this stack is empty
511 * @throws IllegalStateException if current statement is not a DataTreeEffectiveStatement or if its parent is not
512 * a {@link DataTreeAwareEffectiveStatement}
514 public @NonNull DataTreeEffectiveStatement<?> exitToDataTree() {
515 final EffectiveStatement<?, ?> child = exit();
516 checkState(child instanceof DataTreeEffectiveStatement, "Unexpected current %s", child);
517 EffectiveStatement<?, ?> parent = deque.peekFirst();
518 while (parent instanceof ChoiceEffectiveStatement || parent instanceof CaseEffectiveStatement) {
520 parent = deque.peekFirst();
523 checkState(parent == null || parent instanceof DataTreeAwareEffectiveStatement, "Unexpected parent %s", parent);
524 return (DataTreeEffectiveStatement<?>) child;
529 public TypeDefinition<?> resolveLeafref(final LeafrefTypeDefinition type) {
530 final SchemaInferenceStack tmp = copy();
532 LeafrefTypeDefinition current = type;
534 final EffectiveStatement<?, ?> resolved = tmp.resolvePathExpression(current.getPathStatement());
535 checkState(resolved instanceof TypeAware, "Unexpected result %s resultion of %s", resolved, type);
536 final TypeDefinition<?> result = ((TypedDataSchemaNode) resolved).getType();
537 if (result instanceof LeafrefTypeDefinition) {
538 checkArgument(result != type, "Resolution of %s loops back onto itself via %s", type, current);
539 current = (LeafrefTypeDefinition) result;
547 * Resolve a {@link PathExpression}.
550 * Note if this method throws, this stack may be in an undefined state.
552 * @param path Requested path
553 * @return Resolved schema tree child
554 * @throws NullPointerException if {@code path} is null
555 * @throws IllegalArgumentException if the target node cannot be found
556 * @throws VerifyException if path expression is invalid
558 public @NonNull EffectiveStatement<?, ?> resolvePathExpression(final PathExpression path) {
559 final Steps steps = path.getSteps();
560 if (steps instanceof LocationPathSteps) {
561 return resolveLocationPath(((LocationPathSteps) steps).getLocationPath());
562 } else if (steps instanceof DerefSteps) {
563 return resolveDeref((DerefSteps) steps);
565 throw new VerifyException("Unhandled steps " + steps);
569 private @NonNull EffectiveStatement<?, ?> resolveDeref(final DerefSteps deref) {
570 final EffectiveStatement<?, ?> leafRefSchemaNode = currentStatement();
571 final YangLocationPath.Relative derefArg = deref.getDerefArgument();
572 final EffectiveStatement<?, ?> derefStmt = resolveLocationPath(derefArg);
573 checkArgument(derefStmt != null, "Cannot find deref(%s) target node %s in context of %s",
574 derefArg, leafRefSchemaNode);
575 checkArgument(derefStmt instanceof TypedDataSchemaNode, "deref(%s) resolved to non-typed %s", derefArg,
578 // We have a deref() target, decide what to do about it
579 final TypeDefinition<?> targetType = ((TypedDataSchemaNode) derefStmt).getType();
580 if (targetType instanceof InstanceIdentifierTypeDefinition) {
581 // Static inference breaks down, we cannot determine where this points to
582 // FIXME: dedicated exception, users can recover from it, derive from IAE
583 throw new UnsupportedOperationException("Cannot infer instance-identifier reference " + targetType);
586 // deref() is defined only for instance-identifier and leafref types, handle the latter
587 checkArgument(targetType instanceof LeafrefTypeDefinition, "Illegal target type %s", targetType);
589 final PathExpression dereferencedLeafRefPath = ((LeafrefTypeDefinition) targetType).getPathStatement();
590 EffectiveStatement<?, ?> derefNode = resolvePathExpression(dereferencedLeafRefPath);
591 checkArgument(derefStmt != null, "Can not find target node of dereferenced node %s", derefStmt);
592 checkArgument(derefNode instanceof LeafSchemaNode, "Unexpected %s reference in %s", deref,
593 dereferencedLeafRefPath);
594 return resolveLocationPath(deref.getRelativePath());
597 private @NonNull EffectiveStatement<?, ?> resolveLocationPath(final YangLocationPath path) {
598 // get the default namespace before we clear and loose our deque
599 final QNameModule defaultNamespace = deque.isEmpty() ? null : ((QName) deque.peek().argument()).getModule();
600 if (path.isAbsolute()) {
604 EffectiveStatement<?, ?> current = null;
605 for (Step step : path.getSteps()) {
606 final YangXPathAxis axis = step.getAxis();
609 verify(step instanceof AxisStep, "Unexpected parent step %s", step);
611 current = exitToDataTree();
612 } catch (IllegalStateException | NoSuchElementException e) {
613 throw new IllegalArgumentException("Illegal parent access in " + path, e);
617 verify(step instanceof QNameStep, "Unexpected child step %s", step);
618 current = enterChild((QNameStep) step, defaultNamespace);
621 throw new VerifyException("Unexpected step " + step);
625 return verifyNotNull(current);
628 private @NonNull EffectiveStatement<?, ?> enterChild(final QNameStep step, final QNameModule defaultNamespace) {
629 final AbstractQName toResolve = step.getQName();
631 if (toResolve instanceof QName) {
632 qname = (QName) toResolve;
633 } else if (toResolve instanceof UnqualifiedQName) {
634 checkArgument(defaultNamespace != null, "Can not find target module of step %s", step);
635 qname = ((UnqualifiedQName) toResolve).bindTo(defaultNamespace);
637 throw new VerifyException("Unexpected child step QName " + toResolve);
639 return enterDataTree(qname);
643 * Return an {@link Inference} equivalent of current state.
645 * @return An {@link Inference}
647 public @NonNull Inference toInference() {
648 return new Inference(effectiveModel, deque.clone(), currentModule, groupingDepth, clean);
652 * Return an {@link SchemaTreeInference} equivalent of current state.
654 * @return An {@link SchemaTreeInference}
655 * @throws IllegalStateException if current state cannot be converted to a {@link SchemaTreeInference}
657 public @NonNull SchemaTreeInference toSchemaTreeInference() {
658 return DefaultSchemaTreeInference.of(getEffectiveModelContext(), toSchemaNodeIdentifier());
662 * Convert current state into an absolute schema node identifier.
664 * @return Absolute schema node identifier representing current state
665 * @throws IllegalStateException if current state is not instantiated
667 public @NonNull Absolute toSchemaNodeIdentifier() {
668 checkState(inInstantiatedContext(), "Cannot convert uninstantiated context %s", this);
669 return Absolute.of(ImmutableList.<QName>builderWithExpectedSize(deque.size())
670 .addAll(simplePathFromRoot())
675 * Convert current state into a SchemaPath.
677 * @return Absolute SchemaPath representing current state
678 * @throws IllegalStateException if current state is not instantiated
679 * @deprecated This method is meant only for interoperation with SchemaPath-based APIs.
682 public @NonNull SchemaPath toSchemaPath() {
683 SchemaPath ret = SchemaPath.ROOT;
684 final Iterator<QName> it = simplePathFromRoot();
685 while (it.hasNext()) {
686 ret = ret.createChild(it.next());
692 * Return an iterator along {@link SchemaPath#getPathFromRoot()}. This method is a faster equivalent of
693 * {@code toSchemaPath().getPathFromRoot().iterator()}.
695 * @return An unmodifiable iterator
698 public @NonNull Iterator<QName> schemaPathIterator() {
699 return Iterators.unmodifiableIterator(simplePathFromRoot());
703 public String toString() {
704 return MoreObjects.toStringHelper(this).add("stack", deque).toString();
707 private @NonNull GroupingEffectiveStatement pushGrouping(final @NonNull QName nodeIdentifier) {
708 final EffectiveStatement<?, ?> parent = deque.peekFirst();
709 return parent != null ? pushGrouping(parent, nodeIdentifier) : pushFirstGrouping(nodeIdentifier);
712 private @NonNull GroupingEffectiveStatement pushGrouping(final @NonNull EffectiveStatement<?, ?> parent,
713 final @NonNull QName nodeIdentifier) {
714 final GroupingEffectiveStatement ret = parent.streamEffectiveSubstatements(GroupingEffectiveStatement.class)
715 .filter(stmt -> nodeIdentifier.equals(stmt.argument()))
717 .orElseThrow(() -> new IllegalArgumentException("Grouping " + nodeIdentifier + " not present"));
723 private @NonNull GroupingEffectiveStatement pushFirstGrouping(final @NonNull QName nodeIdentifier) {
724 final ModuleEffectiveStatement module = getModule(nodeIdentifier);
725 final GroupingEffectiveStatement ret = pushGrouping(module, nodeIdentifier);
726 currentModule = module;
730 private @NonNull SchemaTreeEffectiveStatement<?> pushSchema(final @NonNull QName nodeIdentifier) {
731 final EffectiveStatement<?, ?> parent = deque.peekFirst();
732 return parent != null ? pushSchema(parent, nodeIdentifier) : pushFirstSchema(nodeIdentifier);
735 private @NonNull SchemaTreeEffectiveStatement<?> pushSchema(final EffectiveStatement<?, ?> parent,
736 final @NonNull QName nodeIdentifier) {
737 checkState(parent instanceof SchemaTreeAwareEffectiveStatement, "Cannot descend schema tree at %s", parent);
738 return pushSchema((SchemaTreeAwareEffectiveStatement<?, ?>) parent, nodeIdentifier);
741 private @NonNull SchemaTreeEffectiveStatement<?> pushSchema(
742 final @NonNull SchemaTreeAwareEffectiveStatement<?, ?> parent, final @NonNull QName nodeIdentifier) {
743 final SchemaTreeEffectiveStatement<?> ret = parent.findSchemaTreeNode(nodeIdentifier).orElseThrow(
744 () -> new IllegalArgumentException("Schema tree child " + nodeIdentifier + " not present"));
749 private @NonNull SchemaTreeEffectiveStatement<?> pushFirstSchema(final @NonNull QName nodeIdentifier) {
750 final ModuleEffectiveStatement module = getModule(nodeIdentifier);
751 final SchemaTreeEffectiveStatement<?> ret = pushSchema(module, nodeIdentifier);
752 currentModule = module;
756 private @NonNull DataTreeEffectiveStatement<?> pushData(final @NonNull QName nodeIdentifier) {
757 final EffectiveStatement<?, ?> parent = deque.peekFirst();
758 return parent != null ? pushData(parent, nodeIdentifier) : pushFirstData(nodeIdentifier);
761 private @NonNull DataTreeEffectiveStatement<?> pushData(final EffectiveStatement<?, ?> parent,
762 final @NonNull QName nodeIdentifier) {
763 checkState(parent instanceof DataTreeAwareEffectiveStatement, "Cannot descend data tree at %s", parent);
764 return pushData((DataTreeAwareEffectiveStatement<?, ?>) parent, nodeIdentifier);
767 private @NonNull DataTreeEffectiveStatement<?> pushData(final @NonNull DataTreeAwareEffectiveStatement<?, ?> parent,
768 final @NonNull QName nodeIdentifier) {
769 final DataTreeEffectiveStatement<?> ret = parent.findDataTreeNode(nodeIdentifier).orElseThrow(
770 () -> new IllegalArgumentException("Data tree child " + nodeIdentifier + " not present"));
776 private @NonNull DataTreeEffectiveStatement<?> pushFirstData(final @NonNull QName nodeIdentifier) {
777 final ModuleEffectiveStatement module = getModule(nodeIdentifier);
778 final DataTreeEffectiveStatement<?> ret = pushData(module, nodeIdentifier);
779 currentModule = module;
783 private @NonNull TypedefEffectiveStatement pushTypedef(final @NonNull QName nodeIdentifier) {
784 final EffectiveStatement<?, ?> parent = deque.peekFirst();
785 return parent != null ? pushTypedef(parent, nodeIdentifier) : pushFirstTypedef(nodeIdentifier);
788 private @NonNull TypedefEffectiveStatement pushTypedef(final @NonNull EffectiveStatement<?, ?> parent,
789 final @NonNull QName nodeIdentifier) {
790 // TODO: 8.0.0: revisit this once we have TypedefNamespace working
791 final TypedefEffectiveStatement ret = parent.streamEffectiveSubstatements(TypedefEffectiveStatement.class)
792 .filter(stmt -> nodeIdentifier.equals(stmt.argument()))
794 .orElseThrow(() -> new IllegalArgumentException("Typedef " + nodeIdentifier + " not present"));
799 private @NonNull TypedefEffectiveStatement pushFirstTypedef(final @NonNull QName nodeIdentifier) {
800 final ModuleEffectiveStatement module = getModule(nodeIdentifier);
801 final TypedefEffectiveStatement ret = pushTypedef(module, nodeIdentifier);
802 currentModule = module;
806 private @NonNull ModuleEffectiveStatement getModule(final @NonNull QName nodeIdentifier) {
807 final ModuleEffectiveStatement module = effectiveModel.getModuleStatements().get(nodeIdentifier.getModule());
808 checkArgument(module != null, "Module for %s not found", nodeIdentifier);
812 // Unified access to queue iteration for addressing purposes. Since we keep 'logical' steps as executed by user
813 // at this point, conversion to SchemaNodeIdentifier may be needed. We dispatch based on 'clean'.
814 private Iterator<QName> simplePathFromRoot() {
815 return clean ? iterateQNames() : reconstructQNames();
818 private Iterator<QName> iterateQNames() {
819 return Iterators.transform(deque.descendingIterator(), stmt -> {
820 final Object argument = stmt.argument();
821 verify(argument instanceof QName, "Unexpected statement %s", stmt);
822 return (QName) argument;
826 // So there are some data tree steps in the stack... we essentially need to convert a data tree item into a series
827 // of schema tree items. This means at least N searches, but after they are done, we get an opportunity to set the
829 private Iterator<QName> reconstructQNames() {
830 // Let's walk all statements and decipher them into a temporary stack
831 final SchemaInferenceStack tmp = new SchemaInferenceStack(effectiveModel, deque.size());
832 final Iterator<EffectiveStatement<?, ?>> it = deque.descendingIterator();
833 while (it.hasNext()) {
834 final EffectiveStatement<?, ?> stmt = it.next();
835 // Order of checks is significant
836 if (stmt instanceof DataTreeEffectiveStatement) {
837 tmp.resolveDataTreeSteps(((DataTreeEffectiveStatement<?>) stmt).argument());
838 } else if (stmt instanceof ChoiceEffectiveStatement) {
839 tmp.resolveChoiceSteps(((ChoiceEffectiveStatement) stmt).argument());
840 } else if (stmt instanceof SchemaTreeEffectiveStatement) {
841 tmp.enterSchemaTree(((SchemaTreeEffectiveStatement<?> )stmt).argument());
842 } else if (stmt instanceof GroupingEffectiveStatement) {
843 tmp.enterGrouping(((GroupingEffectiveStatement) stmt).argument());
844 } else if (stmt instanceof TypedefEffectiveStatement) {
845 tmp.enterTypedef(((TypedefEffectiveStatement) stmt).argument());
847 throw new VerifyException("Unexpected statement " + stmt);
851 // if the sizes match, we did not jump through hoops. let's remember that for future.
852 clean = deque.size() == tmp.deque.size();
853 return tmp.iterateQNames();
856 private void resolveChoiceSteps(final @NonNull QName nodeIdentifier) {
857 final EffectiveStatement<?, ?> parent = deque.peekFirst();
858 if (parent instanceof ChoiceEffectiveStatement) {
859 resolveChoiceSteps((ChoiceEffectiveStatement) parent, nodeIdentifier);
861 enterSchemaTree(nodeIdentifier);
865 private void resolveChoiceSteps(final @NonNull ChoiceEffectiveStatement parent,
866 final @NonNull QName nodeIdentifier) {
867 for (EffectiveStatement<?, ?> stmt : parent.effectiveSubstatements()) {
868 if (stmt instanceof CaseEffectiveStatement) {
869 final CaseEffectiveStatement caze = (CaseEffectiveStatement) stmt;
870 final SchemaTreeEffectiveStatement<?> found = caze.findSchemaTreeNode(nodeIdentifier).orElse(null);
871 if (found instanceof ChoiceEffectiveStatement) {
878 throw new VerifyException("Failed to resolve " + nodeIdentifier + " in " + parent);
881 private void resolveDataTreeSteps(final @NonNull QName nodeIdentifier) {
882 final EffectiveStatement<?, ?> parent = deque.peekFirst();
883 if (parent != null) {
884 verify(parent instanceof SchemaTreeAwareEffectiveStatement, "Unexpected parent %s", parent);
885 resolveDataTreeSteps((SchemaTreeAwareEffectiveStatement<?, ?>) parent, nodeIdentifier);
889 final ModuleEffectiveStatement module = getModule(nodeIdentifier);
890 resolveDataTreeSteps(module, nodeIdentifier);
891 currentModule = module;
894 private void resolveDataTreeSteps(final @NonNull SchemaTreeAwareEffectiveStatement<?, ?> parent,
895 final @NonNull QName nodeIdentifier) {
896 // The algebra of identifiers in 'schema tree versus data tree':
897 // - data tree parents are always schema tree parents
898 // - data tree children are always schema tree children
900 // that implies that a data tree parent must satisfy schema tree queries with data tree children,
901 // so a successful lookup of 'data tree parent -> child' and 'schema tree parent -> child' has to be the same
902 // for a direct lookup.
903 final SchemaTreeEffectiveStatement<?> found = parent.findSchemaTreeNode(nodeIdentifier).orElse(null);
904 if (found instanceof DataTreeEffectiveStatement) {
905 // ... and it did, we are done
910 // Alright, so now it's down to filtering choice/case statements. For that we keep some globally-reused state
911 // and employ a recursive match.
912 final Deque<EffectiveStatement<QName, ?>> match = new ArrayDeque<>();
913 for (EffectiveStatement<?, ?> stmt : parent.effectiveSubstatements()) {
914 if (stmt instanceof ChoiceEffectiveStatement
915 && searchChoice(match, (ChoiceEffectiveStatement) stmt, nodeIdentifier)) {
916 match.descendingIterator().forEachRemaining(deque::push);
921 throw new VerifyException("Failed to resolve " + nodeIdentifier + " in " + parent);
924 private static boolean searchCase(final @NonNull Deque<EffectiveStatement<QName, ?>> result,
925 final @NonNull CaseEffectiveStatement parent, final @NonNull QName nodeIdentifier) {
927 for (EffectiveStatement<?, ?> stmt : parent.effectiveSubstatements()) {
928 if (stmt instanceof DataTreeEffectiveStatement && nodeIdentifier.equals(stmt.argument())) {
929 result.push((DataTreeEffectiveStatement<?>) stmt);
932 if (stmt instanceof ChoiceEffectiveStatement
933 && searchChoice(result, (ChoiceEffectiveStatement) stmt, nodeIdentifier)) {
941 private static boolean searchChoice(final @NonNull Deque<EffectiveStatement<QName, ?>> result,
942 final @NonNull ChoiceEffectiveStatement parent, final @NonNull QName nodeIdentifier) {
944 for (EffectiveStatement<?, ?> stmt : parent.effectiveSubstatements()) {
945 if (stmt instanceof CaseEffectiveStatement
946 && searchCase(result, (CaseEffectiveStatement) stmt, nodeIdentifier)) {
954 private static <T> @NonNull T checkNonNullState(final @Nullable T obj) {
956 throw new IllegalStateException("Cannot execute on empty stack");