#fixed code
                              private Map<String, byte[]> convertToBytearrayMap(Map<String,ByteIterator> values) {
    Map<String, byte[]> retVal = new HashMap<String, byte[]>();
    for (Map.Entry<String, ByteIterator> entry : values.entrySet()) {
      retVal.put(entry.getKey(), entry.getValue().toArray());
    }
    return retVal;
  }
#vulnerable code 
                              private Map<String, byte[]> convertToBytearrayMap(Map<String,ByteIterator> values) {
    Map<String, byte[]> retVal = new HashMap<String, byte[]>();
    for (String key : values.keySet()) {
      retVal.put(key, values.get(key).toArray());
    }
    return retVal;
  } 
                            #location 4 
                            #vulnerability type NULL_DEREFERENCE