DIGIT_MATCHER.or(LETTER_MATCHER).or(DASH_MATCHER);

  /**
   * Helper method for {@link #validateSyntax(List)}. Validates that one part of a domain name is
   * valid.
   *
   * @param part The domain name part to be validated
   * @param isFinalPart Is this the final (rightmost) domain part?
   * @return Whether the part is valid
   */

    //                                                                           =========
    /**
     * Validates document fields according to index field requirements.
     *
     * @param doc the document to validate
     * @param throwError consumer to handle validation errors
     */

@ExtendWith(MockitoExtension.class)
class CredentialsInternalTest {

    @Mock
    CIFSContext mockContext;

    /**
     * Simple in-test implementation of CredentialsInternal to exercise the API surface.
     * It validates inputs, records calls, and delegates some behavior to collaborators
     * so we can verify interactions.
     */
    static class TestCredentials implements CredentialsInternal {
        private final String domain;

            throw new SsoLoginException("unexpected set of artifacts received");
        }
    }

    /**
     * Validates the OAuth2 state parameter.
     * @param session The HTTP session containing stored state data.
     * @param state The state parameter to validate.
     * @return The validated state data.
     */
    protected StateData validateState(final HttpSession session, final String state) {

        });
        return redirectWith(getClass(), moreUrl("list/1").params("dictId", form.dictId));
    }

    /**
     * Update an existing stemmer override item.
     * Validates the form data and updates the item in the dictionary.
     *
     * @param form The edit form containing updated item data
     * @return HTML response redirecting to the list page on success
     */
    @Execute

            throw new CrawlerSystemException("Could not create a temp file.", e);
        }
    }

    /**
     * Validates that the input stream is not null.
     * This is a common validation performed by most extractors.
     *
     * @param in The input stream to validate
     * @throws CrawlerSystemException if the input stream is null
     */
    protected void validateInputStream(final InputStream in) {

**Key Scenarios**:
- ✅ Valid filename extraction
- ✅ Null parameters handling
- ✅ Empty/missing resource name
- ✅ Special characters in filename (Japanese, paths)
- ✅ Input stream not consumed (only validated)
- ✅ Whitespace and empty string handling

---

### 3. ArchiveExtractorErrorHandlingTest.java
**Purpose**: Test improved error handling in archive extractors.

**Key Test Areas**:
- Enhanced error messages

    }

    /**
     * Extracts the filename from the parameters.
     *
     * <p>Note: The input stream is validated for consistency with the Extractor interface,
     * but is not actually read. Only the resource name from the parameters is used.</p>
     *
     * @param in The input stream (validated but not read)
     * @param params The parameters map, expected to contain ExtractData.RESOURCE_NAME_KEY

        copyBeanToBean(entity, body, copyOp -> {
            copyOp.excludeNull();
        });
        return body;
    }

    /**
     * Validates if the given web configuration ID exists.
     *
     * @param webconfigId the web configuration ID to validate
     * @return true if the web configuration exists, false otherwise
     */
    protected Boolean isValidWebConfigId(final String webconfigId) {

        copyBeanToBean(entity, body, copyOp -> {
            copyOp.excludeNull();
        });
        return body;
    }

    /**
     * Validates if the given web configuration ID exists.
     *
     * @param webconfigId the web configuration ID to validate
     * @return true if the web configuration exists, false otherwise
     */
    protected Boolean isValidWebConfigId(final String webconfigId) {