code: public void setValue(String field, byte[] value) throws IOException {
          int hash = Arrays.hashCode(field.getBytes());
          if (!structure.valueHash2Index.containsKey(hash)) {
              throw new IOException("The field " + field + " is unknown.");
          }
          setValue(structure.valueHash2Index.get(hash), value);
      }
docs: Sets the value belonging to the given field.
  
  @param field
  the name of the field
  @param value
  the value to set
  @throws IOException