*/
package org.opendaylight.yangtools.yang.parser.stmt.reactor;
+import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Verify.verify;
+import com.google.common.base.MoreObjects;
+import com.google.common.base.MoreObjects.ToStringHelper;
import com.google.common.base.VerifyException;
import java.util.Collection;
+import java.util.Map;
+import java.util.Optional;
+import java.util.Set;
+import org.eclipse.jdt.annotation.NonNull;
+import org.eclipse.jdt.annotation.Nullable;
+import org.opendaylight.yangtools.yang.common.QName;
+import org.opendaylight.yangtools.yang.common.QNameModule;
+import org.opendaylight.yangtools.yang.common.YangVersion;
+import org.opendaylight.yangtools.yang.model.api.SchemaPath;
import org.opendaylight.yangtools.yang.model.api.meta.DeclaredStatement;
import org.opendaylight.yangtools.yang.model.api.meta.EffectiveStatement;
+import org.opendaylight.yangtools.yang.model.api.meta.StatementDefinition;
+import org.opendaylight.yangtools.yang.model.api.stmt.AugmentStatement;
+import org.opendaylight.yangtools.yang.model.api.stmt.ConfigEffectiveStatement;
+import org.opendaylight.yangtools.yang.model.api.stmt.DeviationStatement;
+import org.opendaylight.yangtools.yang.model.api.stmt.RefineStatement;
+import org.opendaylight.yangtools.yang.model.api.stmt.SchemaNodeIdentifier;
+import org.opendaylight.yangtools.yang.model.api.stmt.UsesStatement;
+import org.opendaylight.yangtools.yang.model.repo.api.SourceIdentifier;
+import org.opendaylight.yangtools.yang.parser.spi.meta.CopyType;
+import org.opendaylight.yangtools.yang.parser.spi.meta.EffectiveStmtCtx.Current;
+import org.opendaylight.yangtools.yang.parser.spi.meta.InferenceException;
+import org.opendaylight.yangtools.yang.parser.spi.meta.ModelActionBuilder;
+import org.opendaylight.yangtools.yang.parser.spi.meta.ModelProcessingPhase;
+import org.opendaylight.yangtools.yang.parser.spi.meta.ModelProcessingPhase.ExecutionOrder;
+import org.opendaylight.yangtools.yang.parser.spi.meta.NamespaceBehaviour.Registry;
+import org.opendaylight.yangtools.yang.parser.spi.meta.ParserNamespace;
+import org.opendaylight.yangtools.yang.parser.spi.meta.StmtContext;
import org.opendaylight.yangtools.yang.parser.spi.meta.StmtContext.Mutable;
+import org.opendaylight.yangtools.yang.parser.spi.meta.StmtContextUtils;
+import org.opendaylight.yangtools.yang.parser.spi.source.SourceException;
+import org.opendaylight.yangtools.yang.parser.spi.source.SupportedFeaturesNamespace;
+import org.opendaylight.yangtools.yang.parser.spi.source.SupportedFeaturesNamespace.SupportedFeatures;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
* @param <E> Effective Statement representation
*/
abstract class ReactorStmtCtx<A, D extends DeclaredStatement<A>, E extends EffectiveStatement<A, D>>
- extends NamespaceStorageSupport implements Mutable<A, D, E> {
+ extends NamespaceStorageSupport implements Mutable<A, D, E>, Current<A, D> {
private static final Logger LOG = LoggerFactory.getLogger(ReactorStmtCtx.class);
/**
* Substatement refcount tracking. This mechanics deals with retaining substatements for the purposes of
* instantiating their lazy copies in InferredStatementContext. It works in concert with {@link #buildEffective()}
- * and {@link #buildDeclared()}: declared/effective statement views hold an implicit reference and refcount-based
+ * and {@link #declared()}: declared/effective statement views hold an implicit reference and refcount-based
* sweep is not activated until they are done (or this statement is not {@link #isSupportedToBuildEffective}).
*
* <p>
*/
private static final int REFCOUNT_SWEPT = Integer.MIN_VALUE;
+ /**
+ * Effective instance built from this context. This field as dual types. Under normal circumstances in matches the
+ * {@link #buildEffective()} instance. If this context is reused, it can be inflated to {@link EffectiveInstances}
+ * and also act as a common instance reuse site.
+ */
+ private @Nullable E effectiveInstance;
+
+ // Master flag controlling whether this context can yield an effective statement
+ // FIXME: investigate the mechanics that are being supported by this, as it would be beneficial if we can get rid
+ // of this flag -- eliminating the initial alignment shadow used by below gap-filler fields.
+ private boolean isSupportedToBuildEffective = true;
+
+ // EffectiveConfig mapping
+ private static final int MASK_CONFIG = 0x03;
+ private static final int HAVE_CONFIG = 0x04;
+ // Effective instantiation mechanics for StatementContextBase: if this flag is set all substatements are known not
+ // change when instantiated. This includes context-independent statements as well as any statements which are
+ // ignored during copy instantiation.
+ private static final int ALL_INDEPENDENT = 0x08;
+ // Flag bit assignments
+ private static final int IS_SUPPORTED_BY_FEATURES = 0x10;
+ private static final int HAVE_SUPPORTED_BY_FEATURES = 0x20;
+ private static final int IS_IGNORE_IF_FEATURE = 0x40;
+ private static final int HAVE_IGNORE_IF_FEATURE = 0x80;
+ // Have-and-set flag constants, also used as masks
+ private static final int SET_SUPPORTED_BY_FEATURES = HAVE_SUPPORTED_BY_FEATURES | IS_SUPPORTED_BY_FEATURES;
+ private static final int SET_IGNORE_IF_FEATURE = HAVE_IGNORE_IF_FEATURE | IS_IGNORE_IF_FEATURE;
+
+ private static final EffectiveConfig[] EFFECTIVE_CONFIGS;
+
+ static {
+ final EffectiveConfig[] values = EffectiveConfig.values();
+ final int length = values.length;
+ verify(length == 4, "Unexpected EffectiveConfig cardinality %s", length);
+ EFFECTIVE_CONFIGS = values;
+ }
+
+ // Flags for use with SubstatementContext. These are hiding in the alignment shadow created by above boolean and
+ // hence improve memory layout.
+ private byte flags;
+
+ // Flag for use by AbstractResumedStatement, ReplicaStatementContext and InferredStatementContext. Each of them
+ // uses it to indicated a different condition. This is hiding in the alignment shadow created by
+ // 'isSupportedToBuildEffective'.
+ // FIXME: move this out once we have JDK15+
+ private boolean boolFlag;
+
+ // SchemaPath cache for use with SubstatementContext and InferredStatementContext. This hurts RootStatementContext
+ // a bit in terms of size -- but those are only a few and SchemaPath is on its way out anyway.
+ // FIXME: this should become 'QName'
+ private SchemaPath schemaPath;
+
+ ReactorStmtCtx() {
+ // Empty on purpose
+ }
+
+ ReactorStmtCtx(final ReactorStmtCtx<A, D, E> original) {
+ isSupportedToBuildEffective = original.isSupportedToBuildEffective;
+ boolFlag = original.boolFlag;
+ flags = original.flags;
+ }
+
+ // Used by ReplicaStatementContext only
+ ReactorStmtCtx(final ReactorStmtCtx<A, D, E> original, final Void dummy) {
+ boolFlag = isSupportedToBuildEffective = original.isSupportedToBuildEffective;
+ flags = original.flags;
+ }
+
+ //
+ //
+ // Common public interface contracts with simple mechanics. Please keep this in one logical block, so we do not end
+ // up mixing concerns and simple details with more complex logic.
+ //
+ //
+
@Override
public abstract StatementContextBase<?, ?, ?> getParentContext();
+ @Override
+ public abstract RootStatementContext<?, ?, ?> getRoot();
+
+ @Override
+ public abstract Collection<? extends StatementContextBase<?, ?, ?>> mutableDeclaredSubstatements();
+
+ @Override
+ public final @NonNull Registry getBehaviourRegistry() {
+ return getRoot().getBehaviourRegistryImpl();
+ }
+
+ @Override
+ public final YangVersion yangVersion() {
+ return getRoot().getRootVersionImpl();
+ }
+
+ @Override
+ public final void setRootVersion(final YangVersion version) {
+ getRoot().setRootVersionImpl(version);
+ }
+
+ @Override
+ public final void addRequiredSource(final SourceIdentifier dependency) {
+ getRoot().addRequiredSourceImpl(dependency);
+ }
+
+ @Override
+ public final void setRootIdentifier(final SourceIdentifier identifier) {
+ getRoot().setRootIdentifierImpl(identifier);
+ }
+
+ @Override
+ public final boolean isEnabledSemanticVersioning() {
+ return getRoot().isEnabledSemanticVersioningImpl();
+ }
+
+ @Override
+ public final ModelActionBuilder newInferenceAction(final ModelProcessingPhase phase) {
+ return getRoot().getSourceContext().newInferenceAction(phase);
+ }
+
+ @Override
+ public final StatementDefinition publicDefinition() {
+ return definition().getPublicView();
+ }
+
+ @Override
+ public final Parent effectiveParent() {
+ return getParentContext();
+ }
+
+ @Override
+ public final QName moduleName() {
+ final RootStatementContext<?, ?, ?> root = getRoot();
+ return QName.create(StmtContextUtils.getRootModuleQName(root), root.getRawArgument());
+ }
+
+ @Override
+ public final EffectiveStatement<?, ?> original() {
+ return getOriginalCtx().map(StmtContext::buildEffective).orElse(null);
+ }
+
+ //
+ // In the next two methods we are looking for an effective statement. If we already have an effective instance,
+ // defer to it's implementation of the equivalent search. Otherwise we search our substatement contexts.
+ //
+ // Note that the search function is split, so as to allow InferredStatementContext to do its own thing first.
+ //
+
+ @Override
+ public final <X, Z extends EffectiveStatement<X, ?>> @NonNull Optional<X> findSubstatementArgument(
+ final @NonNull Class<Z> type) {
+ final E existing = effectiveInstance;
+ return existing != null ? existing.findFirstEffectiveSubstatementArgument(type)
+ : findSubstatementArgumentImpl(type);
+ }
+
+ @Override
+ public final boolean hasSubstatement(final @NonNull Class<? extends EffectiveStatement<?, ?>> type) {
+ final E existing = effectiveInstance;
+ return existing != null ? existing.findFirstEffectiveSubstatement(type).isPresent() : hasSubstatementImpl(type);
+ }
+
+ // Visible due to InferredStatementContext's override. At this point we do not have an effective instance available.
+ <X, Z extends EffectiveStatement<X, ?>> @NonNull Optional<X> findSubstatementArgumentImpl(
+ final @NonNull Class<Z> type) {
+ return allSubstatementsStream()
+ .filter(ctx -> ctx.isSupportedToBuildEffective() && ctx.producesEffective(type))
+ .findAny()
+ .map(ctx -> (X) ctx.getArgument());
+ }
+
+ // Visible due to InferredStatementContext's override. At this point we do not have an effective instance available.
+ boolean hasSubstatementImpl(final @NonNull Class<? extends EffectiveStatement<?, ?>> type) {
+ return allSubstatementsStream()
+ .anyMatch(ctx -> ctx.isSupportedToBuildEffective() && ctx.producesEffective(type));
+ }
+
+ @Override
+ @Deprecated
+ @SuppressWarnings("unchecked")
+ public final <Z extends EffectiveStatement<A, D>> StmtContext<A, D, Z> caerbannog() {
+ return (StmtContext<A, D, Z>) this;
+ }
+
+ @Override
+ public final String toString() {
+ return addToStringAttributes(MoreObjects.toStringHelper(this).omitNullValues()).toString();
+ }
+
+ protected ToStringHelper addToStringAttributes(final ToStringHelper toStringHelper) {
+ return toStringHelper.add("definition", definition()).add("rawArgument", rawArgument());
+ }
+
+ /**
+ * Return the context in which this statement was defined.
+ *
+ * @return statement definition
+ */
+ abstract @NonNull StatementDefinitionContext<A, D, E> definition();
+
+ //
+ //
+ // NamespaceStorageSupport/Mutable integration methods. Keep these together.
+ //
+ //
+
+ @Override
+ public final <K, V, T extends K, N extends ParserNamespace<K, V>> V namespaceItem(final Class<@NonNull N> type,
+ final T key) {
+ return getBehaviourRegistry().getNamespaceBehaviour(type).getFrom(this, key);
+ }
+
+ @Override
+ public final <K, V, N extends ParserNamespace<K, V>> Map<K, V> namespace(final Class<@NonNull N> type) {
+ return getNamespace(type);
+ }
+
+ @Override
+ public final <K, V, N extends ParserNamespace<K, V>>
+ Map<K, V> localNamespacePortion(final Class<@NonNull N> type) {
+ return getLocalNamespace(type);
+ }
+
+ @Override
+ protected <K, V, N extends ParserNamespace<K, V>> void onNamespaceElementAdded(final Class<N> type, final K key,
+ final V value) {
+ // definition().onNamespaceElementAdded(this, type, key, value);
+ }
+
+ /**
+ * Return the effective statement view of a copy operation. This method may return one of:
+ * <ul>
+ * <li>{@code this}, when the effective view did not change</li>
+ * <li>an InferredStatementContext, when there is a need for inference-equivalent copy</li>
+ * <li>{@code null}, when the statement failed to materialize</li>
+ * </ul>
+ *
+ * @param parent Proposed new parent
+ * @param type Copy operation type
+ * @param targetModule New target module
+ * @return {@link ReactorStmtCtx} holding effective view
+ */
+ abstract @Nullable ReactorStmtCtx<?, ?, ?> asEffectiveChildOf(StatementContextBase<?, ?, ?> parent, CopyType type,
+ QNameModule targetModule);
+
+ @Override
+ public final ReactorStmtCtx<A, D, E> replicaAsChildOf(final Mutable<?, ?, ?> parent) {
+ checkArgument(parent instanceof StatementContextBase, "Unsupported parent %s", parent);
+ return replicaAsChildOf((StatementContextBase<?, ?, ?>) parent);
+ }
+
+ abstract @NonNull ReplicaStatementContext<A, D, E> replicaAsChildOf(@NonNull StatementContextBase<?, ?, ?> parent);
+
+ //
+ //
+ // Statement build entry points -- both public and package-private.
+ //
+ //
+
+ @Override
+ public final E buildEffective() {
+ final E existing;
+ return (existing = effectiveInstance) != null ? existing : loadEffective();
+ }
+
+ private @NonNull E loadEffective() {
+ // Creating an effective statement does not strictly require a declared instance -- there are statements like
+ // 'input', which are implicitly defined.
+ // Our implementation design makes an invariant assumption that buildDeclared() has been called by the time
+ // we attempt to create effective statement:
+ declared();
+
+ final E ret = createEffective();
+ effectiveInstance = ret;
+ // we have called createEffective(), substatements are no longer guarded by us. Let's see if we can clear up
+ // some residue.
+ if (refcount == REFCOUNT_NONE) {
+ sweepOnDecrement();
+ }
+ return ret;
+ }
+
+ abstract @NonNull E createEffective();
+
+ /**
+ * Walk this statement's copy history and return the statement closest to original which has not had its effective
+ * statements modified. This statement and returned substatement logically have the same set of substatements, hence
+ * share substatement-derived state.
+ *
+ * @return Closest {@link ReactorStmtCtx} with equivalent effective substatements
+ */
+ abstract @NonNull ReactorStmtCtx<A, D, E> unmodifiedEffectiveSource();
+
+ @Override
+ public final ModelProcessingPhase getCompletedPhase() {
+ return ModelProcessingPhase.ofExecutionOrder(executionOrder());
+ }
+
+ abstract byte executionOrder();
+
+ /**
+ * Try to execute current {@link ModelProcessingPhase} of source parsing. If the phase has already been executed,
+ * this method does nothing. This must not be called with {@link ExecutionOrder#NULL}.
+ *
+ * @param phase to be executed (completed)
+ * @return true if phase was successfully completed
+ * @throws SourceException when an error occurred in source parsing
+ */
+ final boolean tryToCompletePhase(final byte executionOrder) {
+ return executionOrder() >= executionOrder || doTryToCompletePhase(executionOrder);
+ }
+
+ abstract boolean doTryToCompletePhase(byte targetOrder);
+
+ //
+ //
+ // Flags-based mechanics. These include public interfaces as well as all the crud we have lurking in our alignment
+ // shadow.
+ //
+ //
+
+ @Override
+ public final boolean isSupportedToBuildEffective() {
+ return isSupportedToBuildEffective;
+ }
+
+ @Override
+ public final void setIsSupportedToBuildEffective(final boolean isSupportedToBuildEffective) {
+ this.isSupportedToBuildEffective = isSupportedToBuildEffective;
+ }
+
+ @Override
+ public final boolean isSupportedByFeatures() {
+ final int fl = flags & SET_SUPPORTED_BY_FEATURES;
+ if (fl != 0) {
+ return fl == SET_SUPPORTED_BY_FEATURES;
+ }
+ if (isIgnoringIfFeatures()) {
+ flags |= SET_SUPPORTED_BY_FEATURES;
+ return true;
+ }
+
+ /*
+ * If parent is supported, we need to check if-features statements of this context.
+ */
+ if (isParentSupportedByFeatures()) {
+ // If the set of supported features has not been provided, all features are supported by default.
+ final Set<QName> supportedFeatures = getFromNamespace(SupportedFeaturesNamespace.class,
+ SupportedFeatures.SUPPORTED_FEATURES);
+ if (supportedFeatures == null || StmtContextUtils.checkFeatureSupport(this, supportedFeatures)) {
+ flags |= SET_SUPPORTED_BY_FEATURES;
+ return true;
+ }
+ }
+
+ // Either parent is not supported or this statement is not supported
+ flags |= HAVE_SUPPORTED_BY_FEATURES;
+ return false;
+ }
+
+ protected abstract boolean isParentSupportedByFeatures();
+
+ /**
+ * Config statements are not all that common which means we are performing a recursive search towards the root
+ * every time {@link #effectiveConfig()} is invoked. This is quite expensive because it causes a linear search
+ * for the (usually non-existent) config statement.
+ *
+ * <p>
+ * This method maintains a resolution cache, so once we have returned a result, we will keep on returning the same
+ * result without performing any lookups, solely to support {@link #effectiveConfig()}.
+ *
+ * <p>
+ * Note: use of this method implies that {@link #isIgnoringConfig()} is realized with
+ * {@link #isIgnoringConfig(StatementContextBase)}.
+ */
+ final @NonNull EffectiveConfig effectiveConfig(final ReactorStmtCtx<?, ?, ?> parent) {
+ return (flags & HAVE_CONFIG) != 0 ? EFFECTIVE_CONFIGS[flags & MASK_CONFIG] : loadEffectiveConfig(parent);
+ }
+
+ private @NonNull EffectiveConfig loadEffectiveConfig(final ReactorStmtCtx<?, ?, ?> parent) {
+ final EffectiveConfig parentConfig = parent.effectiveConfig();
+
+ final EffectiveConfig myConfig;
+ if (parentConfig != EffectiveConfig.IGNORED && !definition().support().isIgnoringConfig()) {
+ final Optional<Boolean> optConfig = findSubstatementArgument(ConfigEffectiveStatement.class);
+ if (optConfig.isPresent()) {
+ if (optConfig.orElseThrow()) {
+ // Validity check: if parent is config=false this cannot be a config=true
+ InferenceException.throwIf(parentConfig == EffectiveConfig.FALSE, this,
+ "Parent node has config=false, this node must not be specifed as config=true");
+ myConfig = EffectiveConfig.TRUE;
+ } else {
+ myConfig = EffectiveConfig.FALSE;
+ }
+ } else {
+ // If "config" statement is not specified, the default is the same as the parent's "config" value.
+ myConfig = parentConfig;
+ }
+ } else {
+ myConfig = EffectiveConfig.IGNORED;
+ }
+
+ flags = (byte) (flags & ~MASK_CONFIG | HAVE_CONFIG | myConfig.ordinal());
+ return myConfig;
+ }
+
+ protected abstract boolean isIgnoringConfig();
+
+ /**
+ * This method maintains a resolution cache for ignore config, so once we have returned a result, we will
+ * keep on returning the same result without performing any lookups. Exists only to support
+ * {@link SubstatementContext#isIgnoringConfig()}.
+ *
+ * <p>
+ * Note: use of this method implies that {@link #isConfiguration()} is realized with
+ * {@link #effectiveConfig(StatementContextBase)}.
+ */
+ final boolean isIgnoringConfig(final StatementContextBase<?, ?, ?> parent) {
+ return EffectiveConfig.IGNORED == effectiveConfig(parent);
+ }
+
+ protected abstract boolean isIgnoringIfFeatures();
+
+ /**
+ * This method maintains a resolution cache for ignore if-feature, so once we have returned a result, we will
+ * keep on returning the same result without performing any lookups. Exists only to support
+ * {@link SubstatementContext#isIgnoringIfFeatures()}.
+ */
+ final boolean isIgnoringIfFeatures(final StatementContextBase<?, ?, ?> parent) {
+ final int fl = flags & SET_IGNORE_IF_FEATURE;
+ if (fl != 0) {
+ return fl == SET_IGNORE_IF_FEATURE;
+ }
+ if (definition().support().isIgnoringIfFeatures() || parent.isIgnoringIfFeatures()) {
+ flags |= SET_IGNORE_IF_FEATURE;
+ return true;
+ }
+
+ flags |= HAVE_IGNORE_IF_FEATURE;
+ return false;
+ }
+
+ // These two exist only due to memory optimization, should live in AbstractResumedStatement.
+ final boolean fullyDefined() {
+ return boolFlag;
+ }
+
+ final void setFullyDefined() {
+ boolFlag = true;
+ }
+
+ // This exists only due to memory optimization, should live in ReplicaStatementContext. In this context the flag
+ // indicates the need to drop source's reference count when we are being swept.
+ final boolean haveSourceReference() {
+ return boolFlag;
+ }
+
+ // These three exist due to memory optimization, should live in InferredStatementContext. In this context the flag
+ // indicates whether or not this statement's substatement file was modified, i.e. it is not quite the same as the
+ // prototype's file.
+ final boolean isModified() {
+ return boolFlag;
+ }
+
+ final void setModified() {
+ boolFlag = true;
+ }
+
+ final void setUnmodified() {
+ boolFlag = false;
+ }
+
+ // These two exist only for StatementContextBase. Since we are squeezed for size, with only a single bit available
+ // in flags, we default to 'false' and only set the flag to true when we are absolutely sure -- and all other cases
+ // err on the side of caution by taking the time to evaluate each substatement separately.
+ final boolean allSubstatementsContextIndependent() {
+ return (flags & ALL_INDEPENDENT) != 0;
+ }
+
+ final void setAllSubstatementsContextIndependent() {
+ flags |= ALL_INDEPENDENT;
+ }
+
+ //
+ //
+ // Various functionality from AbstractTypeStatementSupport. This used to work on top of SchemaPath, now it still
+ // lives here. Ultimate future is either proper graduation or (more likely) move to AbstractTypeStatementSupport.
+ //
+ //
+
+ @Override
+ public final QName argumentAsTypeQName() {
+ return interpretAsQName(getRawArgument());
+ }
+
+ @Override
+ public final QNameModule effectiveNamespace() {
+ // FIXME: there has to be a better way to do this
+ return getSchemaPath().getLastComponent().getModule();
+ }
+
+ //
+ //
+ // Common SchemaPath cache. All of this is bound to be removed once YANGTOOLS-1066 is done.
+ //
+ //
+
+ // Exists only to support {SubstatementContext,InferredStatementContext}.schemaPath()
+ @Deprecated
+ final @Nullable SchemaPath substatementGetSchemaPath() {
+ if (schemaPath == null) {
+ schemaPath = createSchemaPath((StatementContextBase<?, ?, ?>) coerceParentContext());
+ }
+ return schemaPath;
+ }
+
+ // FIXME: 7.0.0: this method's logic needs to be moved to the respective StatementSupport classes
+ @Deprecated
+ private SchemaPath createSchemaPath(final StatementContextBase<?, ?, ?> parent) {
+ final SchemaPath parentPath = parent.getSchemaPath();
+ if (StmtContextUtils.isUnknownStatement(this)) {
+ return parentPath.createChild(publicDefinition().getStatementName());
+ }
+ final Object argument = argument();
+ if (argument instanceof QName) {
+ final QName qname = (QName) argument;
+ if (producesDeclared(UsesStatement.class)) {
+ return parentPath;
+ }
+
+ return parentPath.createChild(qname);
+ }
+ if (argument instanceof String) {
+ return parentPath.createChild(interpretAsQName((String) argument));
+ }
+ if (argument instanceof SchemaNodeIdentifier
+ && (producesDeclared(AugmentStatement.class) || producesDeclared(RefineStatement.class)
+ || producesDeclared(DeviationStatement.class))) {
+
+ return parentPath.createChild(((SchemaNodeIdentifier) argument).getNodeIdentifiers());
+ }
+
+ // FIXME: this does not look right, investigate more?
+ return parentPath;
+ }
+
+ private @NonNull QName interpretAsQName(final String argument) {
+ // FIXME: This may yield illegal argument exceptions
+ return StmtContextUtils.qnameFromArgument(getOriginalCtx().orElse(this), argument);
+ }
+
+ //
+ //
+ // Reference counting mechanics start. Please keep these methods in one block for clarity. Note this does not
+ // contribute to state visible outside of this package.
+ //
+ //
+
+ /**
+ * Local knowledge of {@link #refcount} values up to statement root. We use this field to prevent recursive lookups
+ * in {@link #noParentRefs(StatementContextBase)} -- once we discover a parent reference once, we keep that
+ * knowledge and update it when {@link #sweep()} is invoked.
+ */
+ private byte parentRef = PARENTREF_UNKNOWN;
+ private static final byte PARENTREF_UNKNOWN = -1;
+ private static final byte PARENTREF_ABSENT = 0;
+ private static final byte PARENTREF_PRESENT = 1;
+
/**
* Acquire a reference on this context. As long as there is at least one reference outstanding,
* {@link #buildEffective()} will not result in {@link #effectiveSubstatements()} being discarded.
}
if (current <= REFCOUNT_NONE) {
// Underflow, become defunct
+ // FIXME: add a global 'warn once' flag
LOG.warn("Statement refcount underflow, reference counting disabled for {}", this, new Throwable());
refcount = REFCOUNT_DEFUNCT;
return;
refcount = current - 1;
LOG.trace("Refcount {} on {}", refcount, this);
- if (isSweepable()) {
+
+ if (refcount == REFCOUNT_NONE) {
+ lastDecRef();
+ }
+ }
+
+ /**
+ * Return {@code true} if this context has no outstanding references.
+ *
+ * @return True if this context has no outstanding references.
+ */
+ final boolean noRefs() {
+ final int local = refcount;
+ return local < REFCOUNT_NONE || local == REFCOUNT_NONE && noParentRef();
+ }
+
+ private void lastDecRef() {
+ if (noImplictRef()) {
// We are no longer guarded by effective instance
sweepOnDecrement();
+ return;
+ }
+
+ final byte prevRefs = parentRef;
+ if (prevRefs == PARENTREF_ABSENT) {
+ // We are the last reference towards root, any children who observed PARENTREF_PRESENT from us need to be
+ // updated
+ markNoParentRef();
+ } else if (prevRefs == PARENTREF_UNKNOWN) {
+ // Noone observed our parentRef, just update it
+ loadParentRefcount();
}
}
- final void releaseImplicitRef() {
- if (refcount == REFCOUNT_NONE) {
- sweepOnDecrement();
+ static final void markNoParentRef(final Collection<? extends ReactorStmtCtx<?, ?, ?>> substatements) {
+ for (ReactorStmtCtx<?, ?, ?> stmt : substatements) {
+ final byte prevRef = stmt.parentRef;
+ stmt.parentRef = PARENTREF_ABSENT;
+ if (prevRef == PARENTREF_PRESENT && stmt.refcount == REFCOUNT_NONE) {
+ // Child thinks it is pinned down, update its perspective
+ stmt.markNoParentRef();
+ }
+ }
+ }
+
+ abstract void markNoParentRef();
+
+ static final void sweep(final Collection<? extends ReactorStmtCtx<?, ?, ?>> substatements) {
+ for (ReactorStmtCtx<?, ?, ?> stmt : substatements) {
+ stmt.sweep();
}
}
* Sweep this statement context as a result of {@link #sweepSubstatements()}, i.e. when parent is also being swept.
*/
private void sweep() {
- if (isSweepable()) {
+ parentRef = PARENTREF_ABSENT;
+ if (refcount == REFCOUNT_NONE && noImplictRef()) {
LOG.trace("Releasing {}", this);
sweepState();
}
}
- static final void sweep(final Collection<? extends ReactorStmtCtx<?, ?, ?>> substatements) {
- for (ReactorStmtCtx<?, ?, ?> stmt : substatements) {
- stmt.sweep();
- }
- }
-
static final int countUnswept(final Collection<? extends ReactorStmtCtx<?, ?, ?>> substatements) {
int result = 0;
for (ReactorStmtCtx<?, ?, ?> stmt : substatements) {
*/
abstract int sweepSubstatements();
- abstract boolean noImplictRef();
-
// Called when this statement does not have an implicit reference and have reached REFCOUNT_NONE
private void sweepOnDecrement() {
LOG.trace("Sweeping on decrement {}", this);
- if (noParentRefcount()) {
+ if (noParentRef()) {
// No further parent references, sweep our state.
sweepState();
}
}
// parent is potentially reclaimable
- if (noParentRefcount()) {
+ if (noParentRef()) {
LOG.trace("Cleanup {} of parent {}", refcount, this);
if (sweepState()) {
final ReactorStmtCtx<?, ?, ?> parent = getParentContext();
}
}
- // FIXME: cache the resolution of this
- private boolean noParentRefcount() {
+ private boolean noImplictRef() {
+ return effectiveInstance != null || !isSupportedToBuildEffective();
+ }
+
+ private boolean noParentRef() {
+ return parentRefcount() == PARENTREF_ABSENT;
+ }
+
+ private byte parentRefcount() {
+ final byte refs;
+ return (refs = parentRef) != PARENTREF_UNKNOWN ? refs : loadParentRefcount();
+ }
+
+ private byte loadParentRefcount() {
+ return parentRef = calculateParentRefcount();
+ }
+
+ private byte calculateParentRefcount() {
final ReactorStmtCtx<?, ?, ?> parent = getParentContext();
- if (parent != null) {
- // There are three possibilities:
- // - REFCOUNT_NONE, in which case we need to search next parent
- // - negative (< REFCOUNT_NONE), meaning parent is in some stage of sweeping, hence it does not have
- // a reference to us
- // - positive (> REFCOUNT_NONE), meaning parent has an explicit refcount which is holding us down
- final int refs = parent.refcount;
- return refs == REFCOUNT_NONE ? parent.noParentRefcount() : refs < REFCOUNT_NONE;
+ if (parent == null) {
+ return PARENTREF_ABSENT;
+ }
+ // There are three possibilities:
+ // - REFCOUNT_NONE, in which case we need to search next parent
+ // - negative (< REFCOUNT_NONE), meaning parent is in some stage of sweeping, hence it does not have
+ // a reference to us
+ // - positive (> REFCOUNT_NONE), meaning parent has an explicit refcount which is holding us down
+ final int refs = parent.refcount;
+ if (refs == REFCOUNT_NONE) {
+ return parent.parentRefcount();
}
- return true;
+ return refs < REFCOUNT_NONE ? PARENTREF_ABSENT : PARENTREF_PRESENT;
}
private boolean isAwaitingChildren() {
return refcount > REFCOUNT_SWEEPING && refcount < REFCOUNT_NONE;
}
- private boolean isSweepable() {
- return refcount == REFCOUNT_NONE && noImplictRef();
- }
-
private void sweepOnChildDone() {
LOG.trace("Sweeping on child done {}", this);
final int current = refcount;
return true;
}
if (childRefs < 0 || childRefs >= REFCOUNT_DEFUNCT) {
+ // FIXME: add a global 'warn once' flag
LOG.warn("Negative child refcount {} cannot be stored, reference counting disabled for {}", childRefs, this,
new Throwable());
refcount = REFCOUNT_DEFUNCT;