Java tutorial
/* * Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved. * * This program and the accompanying materials are made available under the * terms of the Eclipse Public License v1.0 which accompanies this distribution, * and is available at http://www.eclipse.org/legal/epl-v10.html */ package org.opendaylight.yangtools.yang.parser.repo; import com.google.common.base.Function; import com.google.common.base.Preconditions; import com.google.common.cache.Cache; import com.google.common.cache.CacheBuilder; import com.google.common.collect.Collections2; import com.google.common.collect.ImmutableList; import com.google.common.collect.Iterables; import com.google.common.collect.Maps; import com.google.common.util.concurrent.AsyncFunction; import com.google.common.util.concurrent.CheckedFuture; import com.google.common.util.concurrent.FutureCallback; import com.google.common.util.concurrent.Futures; import com.google.common.util.concurrent.ListenableFuture; import java.util.Collection; import java.util.LinkedHashMap; import java.util.LinkedHashSet; import java.util.List; import java.util.Map; import java.util.Map.Entry; import java.util.Set; import javax.annotation.Nonnull; import org.antlr.v4.runtime.ParserRuleContext; import org.opendaylight.yangtools.antlrv4.code.gen.YangStatementParser.StatementContext; import org.opendaylight.yangtools.util.concurrent.ExceptionMapper; import org.opendaylight.yangtools.util.concurrent.ReflectiveExceptionMapper; import org.opendaylight.yangtools.yang.common.QName; import org.opendaylight.yangtools.yang.model.api.SchemaContext; import org.opendaylight.yangtools.yang.model.repo.api.SchemaContextFactory; import org.opendaylight.yangtools.yang.model.repo.api.SchemaResolutionException; import org.opendaylight.yangtools.yang.model.repo.api.SchemaSourceFilter; import org.opendaylight.yangtools.yang.model.repo.api.SourceIdentifier; import org.opendaylight.yangtools.yang.model.repo.api.StatementParserMode; import org.opendaylight.yangtools.yang.parser.impl.util.YangModelDependencyInfo; import org.opendaylight.yangtools.yang.parser.spi.meta.ReactorException; import org.opendaylight.yangtools.yang.parser.spi.source.SourceException; import org.opendaylight.yangtools.yang.parser.stmt.reactor.CrossSourceStatementReactor; import org.opendaylight.yangtools.yang.parser.stmt.rfc6020.YangInferencePipeline; import org.opendaylight.yangtools.yang.parser.stmt.rfc6020.YangStatementSourceImpl; import org.opendaylight.yangtools.yang.parser.util.ASTSchemaSource; import org.slf4j.Logger; import org.slf4j.LoggerFactory; final class SharedSchemaContextFactory implements SchemaContextFactory { private static final ExceptionMapper<SchemaResolutionException> MAPPER = ReflectiveExceptionMapper .create("resolve sources", SchemaResolutionException.class); private static final Logger LOG = LoggerFactory.getLogger(SharedSchemaContextFactory.class); private final Cache<Collection<SourceIdentifier>, SchemaContext> cache = CacheBuilder.newBuilder().weakValues() .build(); private final Cache<Collection<SourceIdentifier>, SchemaContext> semVerCache = CacheBuilder.newBuilder() .weakValues().build(); private final SharedSchemaRepository repository; // FIXME: ignored right now private final SchemaSourceFilter filter; // FIXME SchemaRepository should be the type for repository parameter instead of SharedSchemaRepository (final implementation) public SharedSchemaContextFactory(final SharedSchemaRepository repository, final SchemaSourceFilter filter) { this.repository = Preconditions.checkNotNull(repository); this.filter = Preconditions.checkNotNull(filter); } @Override public CheckedFuture<SchemaContext, SchemaResolutionException> createSchemaContext( final Collection<SourceIdentifier> requiredSources, final StatementParserMode statementParserMode, final Set<QName> supportedFeatures) { return createSchemaContext(requiredSources, statementParserMode == StatementParserMode.SEMVER_MODE ? this.semVerCache : this.cache, new AssembleSources(supportedFeatures, statementParserMode)); } private ListenableFuture<ASTSchemaSource> requestSource(final SourceIdentifier identifier) { return repository.getSchemaSource(identifier, ASTSchemaSource.class); } private CheckedFuture<SchemaContext, SchemaResolutionException> createSchemaContext( final Collection<SourceIdentifier> requiredSources, final Cache<Collection<SourceIdentifier>, SchemaContext> cache, final AsyncFunction<List<ASTSchemaSource>, SchemaContext> assembleSources) { // Make sources unique final List<SourceIdentifier> uniqueSourceIdentifiers = deDuplicateSources(requiredSources); final SchemaContext existing = cache.getIfPresent(uniqueSourceIdentifiers); if (existing != null) { LOG.debug("Returning cached context {}", existing); return Futures.immediateCheckedFuture(existing); } // Request all sources be loaded ListenableFuture<List<ASTSchemaSource>> sf = Futures .allAsList(Collections2.transform(uniqueSourceIdentifiers, this::requestSource)); // Detect mismatch between requested Source IDs and IDs that are extracted from parsed source // Also remove duplicates if present // We are relying on preserved order of uniqueSourceIdentifiers as well as sf sf = Futures.transform(sf, new SourceIdMismatchDetector(uniqueSourceIdentifiers)); // Assemble sources into a schema context final ListenableFuture<SchemaContext> cf = Futures.transform(sf, assembleSources); // Populate cache when successful Futures.addCallback(cf, new FutureCallback<SchemaContext>() { @Override public void onSuccess(final SchemaContext result) { cache.put(uniqueSourceIdentifiers, result); } @Override public void onFailure(@Nonnull final Throwable t) { LOG.debug("Failed to assemble sources", t); } }); return Futures.makeChecked(cf, MAPPER); } /** * @return set (preserving ordering) from the input collection */ private static List<SourceIdentifier> deDuplicateSources(final Collection<SourceIdentifier> requiredSources) { final Set<SourceIdentifier> uniqueSourceIdentifiers = new LinkedHashSet<>(requiredSources); if (uniqueSourceIdentifiers.size() == requiredSources.size()) { // Can potentially reuse input return ImmutableList.copyOf(requiredSources); } LOG.warn("Duplicate sources requested for schema context, removed duplicate sources: {}", Collections2 .filter(uniqueSourceIdentifiers, input -> Iterables.frequency(requiredSources, input) > 1)); return ImmutableList.copyOf(uniqueSourceIdentifiers); } private static final class SourceIdMismatchDetector implements Function<List<ASTSchemaSource>, List<ASTSchemaSource>> { private final List<SourceIdentifier> sourceIdentifiers; public SourceIdMismatchDetector(final List<SourceIdentifier> sourceIdentifiers) { this.sourceIdentifiers = Preconditions.checkNotNull(sourceIdentifiers); } @Override public List<ASTSchemaSource> apply(final List<ASTSchemaSource> input) { final Map<SourceIdentifier, ASTSchemaSource> filtered = new LinkedHashMap<>(); for (int i = 0; i < input.size(); i++) { final SourceIdentifier expectedSId = sourceIdentifiers.get(i); final ASTSchemaSource astSchemaSource = input.get(i); final SourceIdentifier realSId = astSchemaSource.getIdentifier(); if (!expectedSId.equals(realSId)) { LOG.warn( "Source identifier mismatch for module \"{}\", requested as {} but actually is {}. Using actual id", expectedSId.getName(), expectedSId, realSId); } if (filtered.containsKey(realSId)) { LOG.warn("Duplicate source for module {} detected in reactor", realSId); } filtered.put(realSId, astSchemaSource); } return ImmutableList.copyOf(filtered.values()); } } private static final class AssembleSources implements AsyncFunction<List<ASTSchemaSource>, SchemaContext> { private final Set<QName> supportedFeatures; private final StatementParserMode statementParserMode; private final Function<ASTSchemaSource, SourceIdentifier> getIdentifier; private AssembleSources(final Set<QName> supportedFeatures, final StatementParserMode statementParserMode) { this.supportedFeatures = supportedFeatures; this.statementParserMode = Preconditions.checkNotNull(statementParserMode); switch (statementParserMode) { case SEMVER_MODE: this.getIdentifier = ASTSchemaSource::getSemVerIdentifier; break; default: this.getIdentifier = ASTSchemaSource::getIdentifier; } } @Override public ListenableFuture<SchemaContext> apply(@Nonnull final List<ASTSchemaSource> sources) throws SchemaResolutionException, SourceException, ReactorException { final Map<SourceIdentifier, ASTSchemaSource> srcs = Maps.uniqueIndex(sources, getIdentifier); final Map<SourceIdentifier, YangModelDependencyInfo> deps = Maps.transformValues(srcs, ASTSchemaSource::getDependencyInformation); LOG.debug("Resolving dependency reactor {}", deps); final DependencyResolver res = this.statementParserMode == StatementParserMode.SEMVER_MODE ? SemVerDependencyResolver.create(deps) : RevisionDependencyResolver.create(deps); if (!res.getUnresolvedSources().isEmpty()) { LOG.debug("Omitting models {} due to unsatisfied imports {}", res.getUnresolvedSources(), res.getUnsatisfiedImports()); throw new SchemaResolutionException("Failed to resolve required models", res.getResolvedSources(), res.getUnsatisfiedImports()); } final Map<SourceIdentifier, ParserRuleContext> asts = Maps.transformValues(srcs, ASTSchemaSource::getAST); final CrossSourceStatementReactor.BuildAction reactor = YangInferencePipeline.RFC6020_REACTOR .newBuild(statementParserMode, supportedFeatures); for (final Entry<SourceIdentifier, ParserRuleContext> e : asts.entrySet()) { final ParserRuleContext parserRuleCtx = e.getValue(); Preconditions.checkArgument(parserRuleCtx instanceof StatementContext, "Unsupported context class %s for source %s", parserRuleCtx.getClass(), e.getKey()); reactor.addSource(new YangStatementSourceImpl(e.getKey(), (StatementContext) parserRuleCtx)); } final SchemaContext schemaContext; try { schemaContext = reactor.buildEffective(); } catch (final ReactorException ex) { throw new SchemaResolutionException("Failed to resolve required models", ex.getSourceIdentifier(), ex); } return Futures.immediateCheckedFuture(schemaContext); } } }