docs: protected synchronized void clear()
                      throws ObjectManagerException {
          final String methodName = "clear";
          if (Tracing.isAnyTracingEnabled() && trace.isEntryEnabled())
              trace.entry(this, cclass, methodName);
  
          // No call to super.clear() because we use a WeakValueHashMap.
          inMemoryTokens.clear();
          cachedManagedObjects = new java.lang.ref.SoftReference[cachedManagedObjectsSize];
          managedObjectsToWrite.clear();
          tokensToDelete.clear();
          // No need to clear newFreeSpace because the existing one is cleared just before we flush anyway.
  
          // Allow for two headers to be written at the front of the file.
          storeFileSizeUsed = pageSize * 2;
          freeSpaceByAddressHead = null;
          freeSpaceByLength = new java.util.TreeSet(new LengthComparator());
          freeSpaceStoreArea = null;
  
          // Sequence numbers 0-200 are reserved.    
          sequenceNumber = initialSequenceNumber;
  
          directory = makeDirectory(initialDirectoryMinimumNodeSize, 0, 0);
          directoryReservedSize = directory.spaceRequired();
          reservedSize.set(0);
          setAllocationAllowed();
  
          if (Tracing.isAnyTracingEnabled() && trace.isEntryEnabled())
              trace.exit(this, cclass, methodName);
      }