getCharMappingFile(dictId).ifPresent(file -> {
            if (charMappingItem.getId() == 0) {
                file.insert(charMappingItem);
            } else {
                file.update(charMappingItem);
            }
        });
    }

    /**
     * Deletes a character mapping item from the specified dictionary.
     * <p>

            if (dirManager != null && smbFile.getContext().getConfig().isUseDirectoryLeasing()) {
                return listFilesWithDirectoryLeasing(smbFile, dirManager);
            } else {
                // Fall back to regular directory listing
                return smbFile.listFiles();
            }
        } catch (CIFSException e) {
            throw SmbException.wrap(e);
        }
    }

          }
        }

        // didn't see it, trying to put it instead...
        Dummy sneaky = map.putIfAbsent(sample, Dummy.VALUE);
        if (sneaky == null) {
          return sample;
        } else {
          /* Someone beat us to it! Trying again...
           *
           * Technically this loop not guaranteed to terminate, so theoretically (extremely

            builder.setCredentials(NoCredentials.getInstance());
            if (logger.isDebugEnabled()) {
                logger.debug("Using custom GCS endpoint: {}", endpoint);
            }
        } else {
            // Production: use credentials file or default credentials
            final String credentialsFile = getInitParameter("credentialsFile", null, String.class);
            if (StringUtil.isNotBlank(credentialsFile)) {

<img src="/img/tutorial/custom-response/image01.png">

## Available responses { #available-responses }

Here are some of the available responses.

Keep in mind that you can use `Response` to return anything else, or even create a custom sub-class.

/// note | Technical Details

You could also use `from starlette.responses import HTMLResponse`.

      char c1 = seq.charAt(index++);
      if (c1 < Character.MIN_HIGH_SURROGATE || c1 > Character.MAX_LOW_SURROGATE) {
        // Fast path (first test is probably all we need to do)
        return c1;
      } else if (c1 <= Character.MAX_HIGH_SURROGATE) {
        // If the high surrogate was the last character, return its inverse
        if (index == end) {
          return -c1;
        }

   * implementation.
   */
  protected K standardFirstKey() {
    Entry<K, V> entry = firstEntry();
    if (entry == null) {
      throw new NoSuchElementException();
    } else {
      return entry.getKey();
    }
  }

  @Override
  public @Nullable Entry<K, V> lastEntry() {
    return delegate().lastEntry();
  }

  /**

   * implementation.
   */
  protected K standardFirstKey() {
    Entry<K, V> entry = firstEntry();
    if (entry == null) {
      throw new NoSuchElementException();
    } else {
      return entry.getKey();
    }
  }

  @Override
  public @Nullable Entry<K, V> lastEntry() {
    return delegate().lastEntry();
  }

  /**

            buf.append(quoteEscape(newSegmentation));
            buf.append(',');
            buf.append(quoteEscape(newReading));
            buf.append(',');
            buf.append(quoteEscape(newPos));
        } else {
            buf.append(quoteEscape(token));
            buf.append(',');
            buf.append(quoteEscape(segmentation));
            buf.append(',');
            buf.append(quoteEscape(reading));

            rule = rule.substring(1)
            // We use '\n' for end of value.
            totalExceptionRuleBytes += rule.size + 1
            sortedExceptionRules.add(rule)
          } else {
            totalRuleBytes += rule.size + 1 // We use '\n' for end of value.
            sortedRules.add(rule)
          }
        }
      }