/**
   * Generates an entry for a backup directory based on the provided DN. The DN must contain an RDN
   * component that specifies the path to the backup directory, and that directory must exist and be
   * a valid backup directory.
   *
   * @param entryDN The DN of the backup directory entry to retrieve.
   * @return The requested backup directory entry.
   * @throws DirectoryException If the specified directory does not exist or is not a valid backup
   *     directory, or if the DN does not specify any backup directory.
   */
  private Entry getBackupDirectoryEntry(DN entryDN) throws DirectoryException {
    // Make sure that the DN specifies a backup directory.
    AttributeType t = DirectoryServer.getAttributeType(ATTR_BACKUP_DIRECTORY_PATH, true);
    AttributeValue v = entryDN.getRDN().getAttributeValue(t);
    if (v == null) {
      Message message = ERR_BACKUP_DN_DOES_NOT_SPECIFY_DIRECTORY.get(String.valueOf(entryDN));
      throw new DirectoryException(ResultCode.CONSTRAINT_VIOLATION, message, backupBaseDN, null);
    }

    // Get a handle to the backup directory and the information that it
    // contains.
    BackupDirectory backupDirectory;
    try {
      backupDirectory = BackupDirectory.readBackupDirectoryDescriptor(v.getValue().toString());
    } catch (ConfigException ce) {
      if (debugEnabled()) {
        TRACER.debugCaught(DebugLogLevel.ERROR, ce);
      }

      Message message =
          ERR_BACKUP_INVALID_BACKUP_DIRECTORY.get(String.valueOf(entryDN), ce.getMessage());
      throw new DirectoryException(ResultCode.CONSTRAINT_VIOLATION, message);
    } catch (Exception e) {
      if (debugEnabled()) {
        TRACER.debugCaught(DebugLogLevel.ERROR, e);
      }

      Message message = ERR_BACKUP_ERROR_GETTING_BACKUP_DIRECTORY.get(getExceptionMessage(e));
      throw new DirectoryException(DirectoryServer.getServerErrorResultCode(), message);
    }

    // Construct the backup directory entry to return.
    LinkedHashMap<ObjectClass, String> ocMap = new LinkedHashMap<ObjectClass, String>(2);
    ocMap.put(DirectoryServer.getTopObjectClass(), OC_TOP);

    ObjectClass backupDirOC = DirectoryServer.getObjectClass(OC_BACKUP_DIRECTORY, true);
    ocMap.put(backupDirOC, OC_BACKUP_DIRECTORY);

    LinkedHashMap<AttributeType, List<Attribute>> opAttrs =
        new LinkedHashMap<AttributeType, List<Attribute>>(0);
    LinkedHashMap<AttributeType, List<Attribute>> userAttrs =
        new LinkedHashMap<AttributeType, List<Attribute>>(3);

    ArrayList<Attribute> attrList = new ArrayList<Attribute>(1);
    attrList.add(Attributes.create(t, v));
    userAttrs.put(t, attrList);

    t = DirectoryServer.getAttributeType(ATTR_BACKUP_BACKEND_DN, true);
    attrList = new ArrayList<Attribute>(1);
    attrList.add(
        Attributes.create(
            t, AttributeValues.create(t, backupDirectory.getConfigEntryDN().toString())));
    userAttrs.put(t, attrList);

    Entry e = new Entry(entryDN, ocMap, userAttrs, opAttrs);
    e.processVirtualAttributes();
    return e;
  }