Java tutorial
/* * SonarQube * Copyright (C) 2009-2016 SonarSource SA * mailto:contact AT sonarsource DOT com * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 3 of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this program; if not, write to the Free Software Foundation, * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ package org.sonar.server.computation.component; import com.google.common.base.Function; import com.google.common.base.Predicate; import com.google.common.collect.ImmutableMap; import com.google.common.collect.Maps; import java.util.List; import java.util.Map; import javax.annotation.Nonnull; import javax.annotation.Nullable; import org.sonar.api.utils.log.Loggers; import org.sonar.core.util.logs.Profiler; import static com.google.common.collect.FluentIterable.from; import static com.google.common.collect.Iterables.concat; import static java.util.Objects.requireNonNull; /** * This crawler make any number of {@link TypeAwareVisitor} or {@link PathAwareVisitor} defined in a list visit a component tree, component per component, in the order of the list */ public class VisitorsCrawler implements ComponentCrawler { private final Map<ComponentVisitor, VisitorDuration> visitorCumulativeDurations; private final List<VisitorWrapper> preOrderVisitorWrappers; private final List<VisitorWrapper> postOrderVisitorWrappers; public VisitorsCrawler(Iterable<ComponentVisitor> visitors) { List<VisitorWrapper> visitorWrappers = from(visitors).transform(ToVisitorWrapper.INSTANCE).toList(); this.preOrderVisitorWrappers = from(visitorWrappers).filter(MathPreOrderVisitor.INSTANCE).toList(); this.postOrderVisitorWrappers = from(visitorWrappers).filter(MatchPostOrderVisitor.INSTANCE).toList(); this.visitorCumulativeDurations = from(visitors).toMap(VisitorWrapperToInitialDuration.INSTANCE); } public Map<ComponentVisitor, Long> getCumulativeDurations() { return ImmutableMap .copyOf(Maps.transformValues(this.visitorCumulativeDurations, VisitorDurationToDuration.INSTANCE)); } @Override public void visit(final Component component) { try { visitImpl(component); } catch (RuntimeException e) { VisitException.rethrowOrWrap(e, "Visit of Component {key=%s,type=%s} failed", component.getKey(), component.getType()); } } private void visitImpl(Component component) { MatchVisitorMaxDepth visitorMaxDepth = MatchVisitorMaxDepth.forComponent(component); List<VisitorWrapper> preOrderVisitorWrappersToExecute = from(preOrderVisitorWrappers) .filter(visitorMaxDepth).toList(); List<VisitorWrapper> postOrderVisitorWrappersToExecute = from(postOrderVisitorWrappers) .filter(visitorMaxDepth).toList(); if (preOrderVisitorWrappersToExecute.isEmpty() && postOrderVisitorWrappersToExecute.isEmpty()) { return; } for (VisitorWrapper visitorWrapper : concat(preOrderVisitorWrappers, postOrderVisitorWrappers)) { visitorWrapper.beforeComponent(component); } for (VisitorWrapper visitorWrapper : preOrderVisitorWrappersToExecute) { visitNode(component, visitorWrapper); } visitChildren(component); for (VisitorWrapper visitorWrapper : postOrderVisitorWrappersToExecute) { visitNode(component, visitorWrapper); } for (VisitorWrapper visitorWrapper : concat(preOrderVisitorWrappersToExecute, postOrderVisitorWrappersToExecute)) { visitorWrapper.afterComponent(component); } } private void visitChildren(Component component) { for (Component child : component.getChildren()) { visit(child); } } private void visitNode(Component component, VisitorWrapper visitor) { Profiler profiler = Profiler.create(Loggers.get(visitor.getWrappedVisitor().getClass())) .startTrace("Visiting component {}", component.getKey()); visitor.visitAny(component); switch (component.getType()) { case PROJECT: visitor.visitProject(component); break; case MODULE: visitor.visitModule(component); break; case DIRECTORY: visitor.visitDirectory(component); break; case FILE: visitor.visitFile(component); break; case VIEW: visitor.visitView(component); break; case SUBVIEW: visitor.visitSubView(component); break; case PROJECT_VIEW: visitor.visitProjectView(component); break; default: throw new IllegalStateException(String.format("Unknown type %s", component.getType().name())); } long duration = profiler.stopTrace(); incrementDuration(visitor, duration); } private void incrementDuration(VisitorWrapper visitorWrapper, long duration) { visitorCumulativeDurations.get(visitorWrapper.getWrappedVisitor()).increment(duration); } private enum ToVisitorWrapper implements Function<ComponentVisitor, VisitorWrapper> { INSTANCE; @Override public VisitorWrapper apply(@Nonnull ComponentVisitor componentVisitor) { if (componentVisitor instanceof TypeAwareVisitor) { return new TypeAwareVisitorWrapper((TypeAwareVisitor) componentVisitor); } else if (componentVisitor instanceof PathAwareVisitor) { return new PathAwareVisitorWrapper((PathAwareVisitor) componentVisitor); } else { throw new IllegalArgumentException("Only TypeAwareVisitor and PathAwareVisitor can be used"); } } } private static class MatchVisitorMaxDepth implements Predicate<VisitorWrapper> { private static final Map<Component.Type, MatchVisitorMaxDepth> INSTANCES = buildInstances(); private static Map<Component.Type, MatchVisitorMaxDepth> buildInstances() { ImmutableMap.Builder<Component.Type, MatchVisitorMaxDepth> builder = ImmutableMap.builder(); for (Component.Type type : Component.Type.values()) { builder.put(type, new MatchVisitorMaxDepth(type)); } return builder.build(); } private final Component.Type type; private MatchVisitorMaxDepth(Component.Type type) { this.type = requireNonNull(type); } public static MatchVisitorMaxDepth forComponent(Component component) { return INSTANCES.get(component.getType()); } @Override public boolean apply(@Nonnull VisitorWrapper visitorWrapper) { CrawlerDepthLimit maxDepth = visitorWrapper.getMaxDepth(); return maxDepth.isSameAs(type) || maxDepth.isDeeperThan(type); } } private enum MathPreOrderVisitor implements Predicate<VisitorWrapper> { INSTANCE; @Override public boolean apply(@Nonnull VisitorWrapper visitorWrapper) { return visitorWrapper.getOrder() == ComponentVisitor.Order.PRE_ORDER; } } private enum MatchPostOrderVisitor implements Predicate<VisitorWrapper> { INSTANCE; @Override public boolean apply(@Nonnull VisitorWrapper visitorWrapper) { return visitorWrapper.getOrder() == ComponentVisitor.Order.POST_ORDER; } } private static final class VisitorDuration { private long duration = 0; public void increment(long duration) { this.duration += duration; } public long getDuration() { return duration; } } private enum VisitorWrapperToInitialDuration implements Function<ComponentVisitor, VisitorDuration> { INSTANCE; @Override @Nonnull public VisitorDuration apply(@Nonnull ComponentVisitor visitorWrapper) { return new VisitorDuration(); } } private enum VisitorDurationToDuration implements Function<VisitorDuration, Long> { INSTANCE; @Nullable @Override public Long apply(VisitorDuration input) { return input.getDuration(); } } }