code: public synchronized void print(PrintStream p) {
          for (int i = 0; i < nkeys; i++)
              if (keys[i] != null) {
                  p.print(keys[i] +
                      (values[i] != null ? ": "+values[i]: "") + "\r\n");
              }
          p.print("\r\n");
          p.flush();
      }
docs: Prints the key-value pairs represented by this
  header.  Also prints the RFC required blank line
  at the end. Omits pairs with a null key.