path: root/platform/projectModel-impl/src/com/intellij/openapi/roots/impl/RootIndex.java

/*
 * Copyright 2000-2014 JetBrains s.r.o.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.intellij.openapi.roots.impl;

import com.intellij.openapi.diagnostic.Logger;
import com.intellij.openapi.extensions.Extensions;
import com.intellij.openapi.fileTypes.FileTypeRegistry;
import com.intellij.openapi.module.Module;
import com.intellij.openapi.module.ModuleManager;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.roots.*;
import com.intellij.openapi.roots.impl.libraries.LibraryEx;
import com.intellij.openapi.roots.libraries.Library;
import com.intellij.openapi.util.Condition;
import com.intellij.openapi.util.Pair;
import com.intellij.openapi.util.text.StringUtil;
import com.intellij.openapi.vfs.VfsUtilCore;
import com.intellij.openapi.vfs.VirtualFile;
import com.intellij.openapi.vfs.newvfs.events.VFileEvent;
import com.intellij.util.CollectionQuery;
import com.intellij.util.Query;
import com.intellij.util.containers.ContainerUtil;
import com.intellij.util.containers.MultiMap;
import gnu.trove.TObjectIntHashMap;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import org.jetbrains.jps.model.module.JpsModuleSourceRootType;

import java.util.*;

public class RootIndex extends DirectoryIndex {
  private static final Logger LOG = Logger.getInstance("#com.intellij.openapi.roots.impl.RootIndex");
  private static final DirectoryInfo NULL_INFO = new DirectoryInfo(null, null, null, null, (byte)0) {
    @NotNull
    @Override
    public OrderEntry[] getOrderEntries() {
      throw new UnsupportedOperationException("Not implemented");
    }
  };

  private final Set<VirtualFile> myProjectExcludedRoots = ContainerUtil.newHashSet();
  private final Set<VirtualFile> myModuleExcludedRoots;
  private final MultiMap<String, VirtualFile> myPackagePrefixRoots = new MultiMap<String, VirtualFile>() {
    @NotNull
    @Override
    protected Collection<VirtualFile> createCollection() {
      return ContainerUtil.newLinkedHashSet();
    }
  };

  private final Map<String, List<VirtualFile>> myDirectoriesByPackageNameCache = ContainerUtil.newConcurrentMap();
  private final InfoCache myInfoCache;
  private final List<JpsModuleSourceRootType<?>> myRootTypes = ContainerUtil.newArrayList();
  private final TObjectIntHashMap<JpsModuleSourceRootType<?>> myRootTypeId = new TObjectIntHashMap<JpsModuleSourceRootType<?>>();
  @NotNull private final Project myProject;
  private volatile Map<VirtualFile, OrderEntry[]> myOrderEntries;

  // made public for Upsource
  public RootIndex(@NotNull Project project, @NotNull InfoCache cache) {
    myProject = project;
    myInfoCache = cache;
    final RootInfo info = buildRootInfo(project);

    Set<VirtualFile> allRoots = info.getAllRoots();
    for (VirtualFile root : allRoots) {
      List<VirtualFile> hierarchy = getHierarchy(root, allRoots, info);
      Pair<DirectoryInfo, String> pair = hierarchy == null ? new Pair<DirectoryInfo, String>(null, null) : calcDirectoryInfo(root, hierarchy, info);
      cacheInfos(root, root, pair.first);
      myPackagePrefixRoots.putValue(pair.second, root);
      if (info.shouldMarkAsProjectExcluded(root, hierarchy)) {
        myProjectExcludedRoots.add(root);
      }
    }

    myModuleExcludedRoots = info.excludedFromModule.keySet();
  }

  @NotNull
  private RootInfo buildRootInfo(@NotNull Project project) {
    final RootInfo info = new RootInfo();
    for (final Module module : ModuleManager.getInstance(project).getModules()) {
      final ModuleRootManager moduleRootManager = ModuleRootManager.getInstance(module);

      for (final VirtualFile contentRoot : moduleRootManager.getContentRoots()) {
        if (!info.contentRootOf.containsKey(contentRoot)) {
          info.contentRootOf.put(contentRoot, module);
        }
      }

      for (ContentEntry contentEntry : moduleRootManager.getContentEntries()) {
        if (!(contentEntry instanceof ContentEntryImpl) || !((ContentEntryImpl)contentEntry).isDisposed()) {
          for (VirtualFile excludeRoot : contentEntry.getExcludeFolderFiles()) {
            info.excludedFromModule.put(excludeRoot, module);
          }
        }

        // Init module sources
        for (final SourceFolder sourceFolder : contentEntry.getSourceFolders()) {
          final VirtualFile sourceFolderRoot = sourceFolder.getFile();
          if (sourceFolderRoot != null) {
            info.rootTypeId.put(sourceFolderRoot, getRootTypeId(sourceFolder.getRootType()));
            info.classAndSourceRoots.add(sourceFolderRoot);
            info.sourceRootOf.putValue(sourceFolderRoot, module);
            info.packagePrefix.put(sourceFolderRoot, sourceFolder.getPackagePrefix());
          }
        }
      }

      for (OrderEntry orderEntry : moduleRootManager.getOrderEntries()) {
        if (orderEntry instanceof LibraryOrSdkOrderEntry) {
          final LibraryOrSdkOrderEntry entry = (LibraryOrSdkOrderEntry)orderEntry;
          final VirtualFile[] sourceRoots = entry.getRootFiles(OrderRootType.SOURCES);
          final VirtualFile[] classRoots = entry.getRootFiles(OrderRootType.CLASSES);

          // Init library sources
          for (final VirtualFile sourceRoot : sourceRoots) {
            info.classAndSourceRoots.add(sourceRoot);
            info.libraryOrSdkSources.add(sourceRoot);
            info.packagePrefix.put(sourceRoot, "");
          }

          // init library classes
          for (final VirtualFile classRoot : classRoots) {
            info.classAndSourceRoots.add(classRoot);
            info.libraryOrSdkClasses.add(classRoot);
            info.packagePrefix.put(classRoot, "");
          }

          if (orderEntry instanceof LibraryOrderEntry) {
            Library library = ((LibraryOrderEntry)orderEntry).getLibrary();
            if (library != null) {
              for (VirtualFile root : ((LibraryEx)library).getExcludedRoots()) {
                info.excludedFromLibraries.putValue(root, library);
              }
              for (VirtualFile root : sourceRoots) {
                info.sourceOfLibraries.putValue(root, library);
              }
              for (VirtualFile root : classRoots) {
                info.classOfLibraries.putValue(root, library);
              }
            }
          }

        }
      }
    }

    for (DirectoryIndexExcludePolicy policy : Extensions.getExtensions(DirectoryIndexExcludePolicy.EP_NAME, project)) {
      Collections.addAll(info.excludedFromProject, policy.getExcludeRootsForProject());
    }
    return info;
  }

  @NotNull
  private Map<VirtualFile, OrderEntry[]> getOrderEntries() {
    Map<VirtualFile, OrderEntry[]> result = myOrderEntries;
    if (result != null) return result;

    MultiMap<VirtualFile, OrderEntry> libClassRootEntries = MultiMap.createSmartList();
    MultiMap<VirtualFile, OrderEntry> libSourceRootEntries = MultiMap.createSmartList();
    MultiMap<VirtualFile, OrderEntry> depEntries = MultiMap.createSmartList();

    for (final Module module : ModuleManager.getInstance(myProject).getModules()) {
      final ModuleRootManager moduleRootManager = ModuleRootManager.getInstance(module);
      for (OrderEntry orderEntry : moduleRootManager.getOrderEntries()) {
        if (orderEntry instanceof ModuleOrderEntry) {
          final Module depModule = ((ModuleOrderEntry)orderEntry).getModule();
          if (depModule != null) {
            VirtualFile[] importedClassRoots = OrderEnumerator.orderEntries(depModule).exportedOnly().recursively().classes().usingCache().getRoots();
            for (VirtualFile importedClassRoot : importedClassRoots) {
              depEntries.putValue(importedClassRoot, orderEntry);
            }
          }
          for (VirtualFile sourceRoot : orderEntry.getFiles(OrderRootType.SOURCES)) {
            depEntries.putValue(sourceRoot, orderEntry);
          }
        }
        else if (orderEntry instanceof LibraryOrSdkOrderEntry) {
          final LibraryOrSdkOrderEntry entry = (LibraryOrSdkOrderEntry)orderEntry;
          for (final VirtualFile sourceRoot : entry.getRootFiles(OrderRootType.SOURCES)) {
            libSourceRootEntries.putValue(sourceRoot, orderEntry);
          }
          for (final VirtualFile classRoot : entry.getRootFiles(OrderRootType.CLASSES)) {
            libClassRootEntries.putValue(classRoot, orderEntry);
          }
        }
      }
    }

    RootInfo rootInfo = buildRootInfo(myProject);
    result = ContainerUtil.newHashMap();
    Set<VirtualFile> allRoots = rootInfo.getAllRoots();
    for (VirtualFile file : allRoots) {
      List<VirtualFile> hierarchy = getHierarchy(file, allRoots, rootInfo);
      result.put(file, hierarchy == null ? OrderEntry.EMPTY_ARRAY : calcOrderEntries(rootInfo, depEntries, libClassRootEntries, libSourceRootEntries, hierarchy));
    }
    myOrderEntries = result;
    return result;
  }

  private static OrderEntry[] calcOrderEntries(@NotNull RootInfo info,
                                               @NotNull MultiMap<VirtualFile, OrderEntry> depEntries,
                                               @NotNull MultiMap<VirtualFile, OrderEntry> libClassRootEntries,
                                               @NotNull MultiMap<VirtualFile, OrderEntry> libSourceRootEntries,
                                               @NotNull List<VirtualFile> hierarchy) {
    @Nullable VirtualFile libraryClassRoot = info.findLibraryRootInfo(hierarchy, false);
    @Nullable VirtualFile librarySourceRoot = info.findLibraryRootInfo(hierarchy, true);
    Set<OrderEntry> orderEntries = ContainerUtil.newLinkedHashSet();
    orderEntries.addAll(info.getLibraryOrderEntries(hierarchy, libraryClassRoot, librarySourceRoot, libClassRootEntries, libSourceRootEntries));
    for (VirtualFile root : hierarchy) {
      orderEntries.addAll(depEntries.get(root));
    }
    VirtualFile moduleContentRoot = info.findModuleRootInfo(hierarchy);
    if (moduleContentRoot != null) {
      ContainerUtil.addIfNotNull(orderEntries, info.getModuleSourceEntry(hierarchy, moduleContentRoot, libClassRootEntries));
    }
    if (orderEntries.isEmpty()) {
      return null;
    }

    OrderEntry[] array = orderEntries.toArray(new OrderEntry[orderEntries.size()]);
    Arrays.sort(array, DirectoryInfo.BY_OWNER_MODULE);
    return array;
  }


  @Override
  public void checkConsistency() {
    for (VirtualFile file : myProjectExcludedRoots) {
      assert file.exists() : file.getPath() + " does not exist";
    }

    for (VirtualFile file : myPackagePrefixRoots.values()) {
      assert file.exists() : file.getPath() + " does not exist";
    }
  }

  private int getRootTypeId(@NotNull JpsModuleSourceRootType<?> rootType) {
    if (myRootTypeId.containsKey(rootType)) {
      return myRootTypeId.get(rootType);
    }

    int id = myRootTypes.size();
    if (id > DirectoryInfo.MAX_ROOT_TYPE_ID) {
      LOG.error("Too many different types of module source roots (" + id  + ") registered: " + myRootTypes);
    }
    myRootTypes.add(rootType);
    myRootTypeId.put(rootType, id);
    return id;
  }

  @Override
  @Nullable
  public DirectoryInfo getInfoForDirectory(@NotNull final VirtualFile dir) {
    if (!dir.isValid()) {
      return null;
    }
    if (!dir.isDirectory()) {
      DirectoryInfo info = myInfoCache.getCachedInfo(dir);
      return info == NULL_INFO ? null : info;
    }

    int count = 0;
    for (VirtualFile root = dir; root != null; root = root.getParent()) {
      if (++count > 1000) {
        throw new IllegalStateException("Possible loop in tree, started at " + dir.getName());
      }
      DirectoryInfo info = myInfoCache.getCachedInfo(root);
      if (info != null) {
        if (!dir.equals(root)) {
          cacheInfos(dir, root, info);
        }
        return info == NULL_INFO ? null : info;
      }

      if (isIgnored(root)) {
        return cacheInfos(dir, root, null);
      }
    }

    return cacheInfos(dir, null, null);
  }

  @Nullable
  private DirectoryInfo cacheInfos(VirtualFile dir, @Nullable VirtualFile stopAt, @Nullable DirectoryInfo info) {
    while (dir != null) {
      myInfoCache.cacheInfo(dir, info == null ? NULL_INFO : info);
      if (dir.equals(stopAt)) {
        break;
      }
      dir = dir.getParent();
    }
    return info;
  }

  @Override
  public boolean isProjectExcludeRoot(@NotNull final VirtualFile dir) {
    return myProjectExcludedRoots.contains(dir);
  }

  @Override
  public boolean isModuleExcludeRoot(@NotNull final VirtualFile dir) {
    return myModuleExcludedRoots.contains(dir);
  }

  @Override
  @NotNull
  public Query<VirtualFile> getDirectoriesByPackageName(@NotNull final String packageName, final boolean includeLibrarySources) {
    List<VirtualFile> result = myDirectoriesByPackageNameCache.get(packageName);
    if (result == null) {
      result = ContainerUtil.newSmartList();
      
      if (StringUtil.isNotEmpty(packageName) && !StringUtil.startsWithChar(packageName, '.')) {
        String shortName = StringUtil.getShortName(packageName);
        for (VirtualFile parentDir : getDirectoriesByPackageName(StringUtil.getPackageName(packageName), true)) {
          VirtualFile child = parentDir.findChild(shortName);
          if (child != null && child.isDirectory() && getInfoForDirectory(child) != null && packageName.equals(getPackageName(child))) {
            result.add(child);
          }
        }
      }

      result.addAll(myPackagePrefixRoots.get(packageName));

      if (!result.isEmpty()) {
        myDirectoriesByPackageNameCache.put(packageName, result);
      }
    }

    if (!includeLibrarySources) {
      result = ContainerUtil.filter(result, new Condition<VirtualFile>() {
        @Override
        public boolean value(VirtualFile file) {
          DirectoryInfo info = getInfoForDirectory(file);
          return info != null && (!info.isInLibrarySource() || info.isInModuleSource() || info.hasLibraryClassRoot());
        }
      });
    }
    return new CollectionQuery<VirtualFile>(result);
  }

  @Override
  @Nullable
  public String getPackageName(@NotNull final VirtualFile dir) {
    if (dir.isDirectory()) {
      if (isIgnored(dir)) {
        return null;
      }

      for (final Map.Entry<String, Collection<VirtualFile>> entry : myPackagePrefixRoots.entrySet()) {
        if (entry.getValue().contains(dir)) {
          return entry.getKey();
        }
      }

      final VirtualFile parent = dir.getParent();
      if (parent != null) {
        return getPackageNameForSubdir(getPackageName(parent), dir.getName());
      }
    }

    return null;
  }

  @Nullable
  protected static String getPackageNameForSubdir(String parentPackageName, @NotNull String subdirName) {
    if (parentPackageName == null) return null;
    return parentPackageName.isEmpty() ? subdirName : parentPackageName + "." + subdirName;
  }

  @Override
  @Nullable
  public JpsModuleSourceRootType<?> getSourceRootType(@NotNull DirectoryInfo directoryInfo) {
    return myRootTypes.get(directoryInfo.getSourceRootTypeId());
  }

  boolean resetOnEvents(@NotNull List<? extends VFileEvent> events) {
    for (VFileEvent event : events) {
      VirtualFile file = event.getFile();
      if (file == null || file.isDirectory()) {
        return true;
      }
    }
    return false;
  }

  @Nullable
  private static List<VirtualFile> getHierarchy(VirtualFile dir, @NotNull Set<VirtualFile> allRoots, @NotNull RootInfo info) {
    List<VirtualFile> hierarchy = ContainerUtil.newArrayList();
    boolean hasContentRoots = false;
    while (dir != null) {
      hasContentRoots |= info.contentRootOf.get(dir) != null;
      if (!hasContentRoots && isIgnored(dir)) {
        return null;
      }
      if (allRoots.contains(dir)) {
        hierarchy.add(dir);
      }
      dir = dir.getParent();
    }
    return hierarchy;
  }

  private static boolean isIgnored(@NotNull VirtualFile dir) {
    return FileTypeRegistry.getInstance().isFileIgnored(dir);
  }

  private static class RootInfo {
    // getDirectoriesByPackageName used to be in this order, some clients might rely on that
    @NotNull final LinkedHashSet<VirtualFile> classAndSourceRoots = ContainerUtil.newLinkedHashSet();

    @NotNull final Set<VirtualFile> libraryOrSdkSources = ContainerUtil.newHashSet();
    @NotNull final Set<VirtualFile> libraryOrSdkClasses = ContainerUtil.newHashSet();
    @NotNull final Map<VirtualFile, Module> contentRootOf = ContainerUtil.newHashMap();
    @NotNull final MultiMap<VirtualFile, Module> sourceRootOf = MultiMap.createSet();
    @NotNull final TObjectIntHashMap<VirtualFile> rootTypeId = new TObjectIntHashMap<VirtualFile>();
    @NotNull final MultiMap<VirtualFile, Library> excludedFromLibraries = MultiMap.createSmartList();
    @NotNull final MultiMap<VirtualFile, Library> classOfLibraries = MultiMap.createSmartList();
    @NotNull final MultiMap<VirtualFile, Library> sourceOfLibraries = MultiMap.createSmartList();
    @NotNull final Set<VirtualFile> excludedFromProject = ContainerUtil.newHashSet();
    @NotNull final Map<VirtualFile, Module> excludedFromModule = ContainerUtil.newHashMap();
    @NotNull final Map<VirtualFile, String> packagePrefix = ContainerUtil.newHashMap();

    @NotNull
    Set<VirtualFile> getAllRoots() {
      LinkedHashSet<VirtualFile> result = ContainerUtil.newLinkedHashSet();
      result.addAll(classAndSourceRoots);
      result.addAll(contentRootOf.keySet());
      result.addAll(excludedFromLibraries.keySet());
      result.addAll(excludedFromModule.keySet());
      result.addAll(excludedFromProject);
      return result;
    }

    private boolean shouldMarkAsProjectExcluded(@NotNull VirtualFile root, @Nullable List<VirtualFile> hierarchy) {
      if (hierarchy == null) return false;
      if (!excludedFromProject.contains(root) && !excludedFromModule.containsKey(root)) return false;
      return ContainerUtil.find(hierarchy, new Condition<VirtualFile>() {
        @Override
        public boolean value(VirtualFile ancestor) {
          return contentRootOf.containsKey(ancestor);
        }
      }) == null;
    }

    @Nullable
    private VirtualFile findModuleRootInfo(@NotNull List<VirtualFile> hierarchy) {
      for (VirtualFile root : hierarchy) {
        Module module = contentRootOf.get(root);
        Module excludedFrom = excludedFromModule.get(root);
        if (module != null && excludedFrom != module) {
          return root;
        }
        if (excludedFrom != null || excludedFromProject.contains(root)) {
          return null;
        }
      }
      return null;
    }

    @Nullable
    private VirtualFile findLibraryRootInfo(@NotNull List<VirtualFile> hierarchy, boolean source) {
      Set<Library> librariesToIgnore = ContainerUtil.newHashSet();
      for (VirtualFile root : hierarchy) {
        librariesToIgnore.addAll(excludedFromLibraries.get(root));
        if (source && libraryOrSdkSources.contains(root) &&
            (!sourceOfLibraries.containsKey(root) || !librariesToIgnore.containsAll(sourceOfLibraries.get(root)))) {
          return root;
        } else if (!source && libraryOrSdkClasses.contains(root) &&
                   (!classOfLibraries.containsKey(root) || !librariesToIgnore.containsAll(classOfLibraries.get(root)))) {
          return root;
        }
      }
      return null;
    }

    private String calcPackagePrefix(@NotNull VirtualFile root,
                                     @NotNull List<VirtualFile> hierarchy,
                                     VirtualFile moduleContentRoot,
                                     VirtualFile libraryClassRoot,
                                     VirtualFile librarySourceRoot) {
      VirtualFile packageRoot = findPackageRootInfo(hierarchy, moduleContentRoot, libraryClassRoot, librarySourceRoot);
      String prefix = packagePrefix.get(packageRoot);
      if (prefix != null && !root.equals(packageRoot)) {
        assert packageRoot != null;
        String relative = VfsUtilCore.getRelativePath(root, packageRoot, '.');
        prefix = StringUtil.isEmpty(prefix) ? relative : prefix + '.' + relative;
      }
      return prefix;
    }

    @Nullable
    private VirtualFile findPackageRootInfo(@NotNull List<VirtualFile> hierarchy,
                                            VirtualFile moduleContentRoot,
                                            VirtualFile libraryClassRoot,
                                            VirtualFile librarySourceRoot) {
      for (VirtualFile root : hierarchy) {
        if (moduleContentRoot != null &&
            sourceRootOf.get(root).contains(contentRootOf.get(moduleContentRoot)) &&
            librarySourceRoot == null) {
          return root;
        }
        if (root.equals(libraryClassRoot) || root.equals(librarySourceRoot)) {
          return root;
        }
        if (root.equals(moduleContentRoot) && !sourceRootOf.containsKey(root) && librarySourceRoot == null && libraryClassRoot == null) {
          return null;
        }
      }
      return null;
    }

    @NotNull
    private LinkedHashSet<OrderEntry> getLibraryOrderEntries(@NotNull List<VirtualFile> hierarchy,
                                                             @Nullable VirtualFile libraryClassRoot,
                                                             @Nullable VirtualFile librarySourceRoot,
                                                             @NotNull MultiMap<VirtualFile, OrderEntry> libClassRootEntries,
                                                             @NotNull MultiMap<VirtualFile, OrderEntry> libSourceRootEntries) {
      LinkedHashSet<OrderEntry> orderEntries = ContainerUtil.newLinkedHashSet();
      for (VirtualFile root : hierarchy) {
        if (root.equals(libraryClassRoot) && !sourceRootOf.containsKey(root)) {
          orderEntries.addAll(libClassRootEntries.get(root));
        }
        if (root.equals(librarySourceRoot) && libraryClassRoot == null) {
          orderEntries.addAll(libSourceRootEntries.get(root));
        }
        if (libClassRootEntries.containsKey(root) || sourceRootOf.containsKey(root) && librarySourceRoot == null) {
          break;
        }
      }
      return orderEntries;
    }

    @Nullable
    private ModuleSourceOrderEntry getModuleSourceEntry(@NotNull List<VirtualFile> hierarchy,
                                                        @NotNull VirtualFile moduleContentRoot,
                                                        @NotNull MultiMap<VirtualFile, OrderEntry> libClassRootEntries) {
      Module module = contentRootOf.get(moduleContentRoot);
      for (VirtualFile root : hierarchy) {
        if (sourceRootOf.get(root).contains(module)) {
          return ContainerUtil.findInstance(ModuleRootManager.getInstance(module).getOrderEntries(), ModuleSourceOrderEntry.class);
        }
        if (libClassRootEntries.containsKey(root)) {
          return null;
        }
      }
      return null;
    }
  }

  @NotNull
  private Pair<DirectoryInfo, String> calcDirectoryInfo(@NotNull final VirtualFile root, @NotNull final List<VirtualFile> hierarchy, @NotNull RootInfo info) {
    VirtualFile moduleContentRoot = info.findModuleRootInfo(hierarchy);
    VirtualFile libraryClassRoot = info.findLibraryRootInfo(hierarchy, false);
    VirtualFile librarySourceRoot = info.findLibraryRootInfo(hierarchy, true);
    if (moduleContentRoot == null && libraryClassRoot == null && librarySourceRoot == null) {
      return new Pair<DirectoryInfo, String>(null, null);
    }

    VirtualFile sourceRoot = info.findPackageRootInfo(hierarchy, moduleContentRoot, null, librarySourceRoot);

    VirtualFile moduleSourceRoot = info.findPackageRootInfo(hierarchy, moduleContentRoot, null, null);
    boolean inModuleSources = moduleSourceRoot != null;
    boolean inLibrarySource = librarySourceRoot != null;
    int typeId = moduleSourceRoot != null ? info.rootTypeId.get(moduleSourceRoot) : 0;

    DirectoryInfo directoryInfo = new DirectoryInfo(info.contentRootOf.get(moduleContentRoot),
                                                    moduleContentRoot,
                                                    sourceRoot,
                                                    libraryClassRoot,
                                                    (byte)DirectoryInfo.createSourceRootTypeData(inModuleSources, inLibrarySource, typeId)) {
      @NotNull
      @Override
      public OrderEntry[] getOrderEntries() {
        OrderEntry[] entries = RootIndex.this.getOrderEntries().get(root);
        return entries == null ? OrderEntry.EMPTY_ARRAY : entries;
      }
    };

    String packagePrefix = info.calcPackagePrefix(root, hierarchy, moduleContentRoot, libraryClassRoot, librarySourceRoot);

    return Pair.create(directoryInfo, packagePrefix);
  }
  
  public interface InfoCache {
    @Nullable DirectoryInfo getCachedInfo(@NotNull VirtualFile dir);
   void cacheInfo(@NotNull VirtualFile dir, @NotNull DirectoryInfo info);
  }
}