#vulnerable code 
                              protected void initialize(final int cachePercent)
    throws IOException
  {
    final long fileBytes = file.length();
    final long cacheSize = (fileBytes / 100) * cachePercent;
    final long cacheModulus = cacheSize == 0 ? fileBytes : cacheSize > fileBytes ? 1 : fileBytes / cacheSize;

    if (cache == null) {
      throw new IllegalStateException("Cannot initialize after close has been called.");
    }

    FileWord a;
    FileWord b = null;
    synchronized (cache) {
      position = 0;
      seek(0);
      cache.clear();
      while ((a = nextWord()) != null) {
        if (b != null && comparator.compare(a.word, b.word) < 0) {
          throw new IllegalArgumentException("File is not sorted correctly for this comparator");
        }
        b = a;
        if (cacheSize > 0 && size % cacheModulus == 0) {
          cache.put(size, a.offset);
        }
        size++;
      }
    }
  } 
                            #location 10 
                            #vulnerability type THREAD_SAFETY_VIOLATION
#fixed code
                              protected void initialize(final int cachePercent)
    throws IOException
  {
    cache = new Cache(file.length(), cachePercent);
    FileWord a;
    FileWord b = null;
    synchronized (cache) {
      position = 0;
      seek(position);
      while ((a = nextWord()) != null) {
        if (b != null && comparator.compare(a.word, b.word) < 0) {
          throw new IllegalArgumentException("File is not sorted correctly for this comparator");
        }
        b = a;
        cache.put(size++, position);
      }
    }
  }