private static final long serialVersionUID = 1L;

            @Override
            public String getTimeAdjustTimeMillis() {
                return "1000.5"; // Invalid for Long parsing
            }

            @Override
            public Long getTimeAdjustTimeMillisAsLong() {
                return 1000L; // Return valid long
            }
        };

        doc.put("url", "https://example.com");
        doc.put("title", "Test Title");
        doc.put("role", "Rguest");
        doc.put("boost", "1.0");
        doc.put("created", "invalid-date");

        final List<VaMessenger<FessMessages>> errorMessages = new ArrayList<>();
        AdminSearchlistAction.validateFields(doc, errorMessages::add);

        assertFalse(errorMessages.isEmpty());

4. **Verify translations:**
   - Navigate through different admin pages
   - Check that labels and messages appear in your language
   - Test error messages by submitting invalid forms

## Configuration Details

### Key Configuration Files

| File | Purpose |
|------|---------|
| `fess_config.properties` | Main configuration file containing `supported.languages` |

background-color: rgba(220, 53, 69, 0.9);\n  border-radius: 0.25rem;\n}\n\n.form-row > .col > .invalid-tooltip,\n.form-row > [class*=\"col-\"] > .invalid-tooltip {\n  left: 5px;\n}\n\n.was-validated :invalid ~ .invalid-feedback,\n.was-validated :invalid ~ .invalid-tooltip,\n.is-invalid ~ .invalid-feedback,\n.is-invalid ~ .invalid-tooltip {\n  display: block;\n}\n\n.was-validated .form-control:invalid, .form-control.is-invalid {\n  border-color: #dc3545;\n  padding-right: calc(1.5em + 0.75rem) !important;\n ...

        assertEquals(0, results.length);
    }

    @Test
    public void test_load_invalidRegex() {
        List<RelatedContent> testData = new ArrayList<>();
        testData.add(createRelatedContent("regex:", "Invalid Regex", ""));
        mockBhv.setTestData(testData);

        // Should not throw exception, just log warning
        relatedContentHelper.load();

labels.searchoptions_menu_labels=Labels
labels.error_title=Error
labels.system_error_title=System Error
labels.contact_site_admin=Please contact your site administrator.
labels.request_error_title=Invalid Request Format.
labels.bad_request=Your request to the URL is invalid.
labels.page_not_found_title=Page Not Found.
labels.check_url=Please check the URL.
labels.busy_title=Service Temporarily Unavailable

    }

    @Test
    public void test_getLanguageItems_cacheException() {
        final List<Map<String, String>> items = systemHelper.getLanguageItems(new Locale("invalid"));
        assertNotNull(items);
        // The cache may work fine even with invalid locale, so check size is reasonable
        assertTrue(items.size() >= 1);
    }

    @Test
    public void test_getHostname_unknownHost() {

```bash
curl -X GET "http://localhost:8080/api/admin/webconfig" \
  -u admin:admin
```

---

## Troubleshooting

### Common Migration Issues

#### Issue: Import fails with "Invalid format"

**Solution**:
- Ensure NDJSON files have one valid JSON object per line
- Check for UTF-8 encoding
- Validate JSON syntax with `jq`:
  ```bash
  cat documents.ndjson | jq empty
  ```

        try {
            documentItems = searchInternal(query, params, userBean);
        } catch (final InvalidQueryException e) {
            if (logger.isDebugEnabled()) {
                logger.debug("Invalid query: {}", query, e);
            }
            query = ComponentUtil.getQueryStringBuilder().params(params).sortField(params.getSort()).escape(true).build();
            documentItems = searchInternal(query, params, userBean);

        final String value = decodeId(id);
        final String[] values = split(value, "/").get(stream -> stream.filter(StringUtil::isNotEmpty).toArray(n -> new String[n]));
        if (values.length == 0) {
            // invalid?
            return new PathInfo(StringUtil.EMPTY, StringUtil.EMPTY);
        }
        if (values.length == 1) {
            return new PathInfo(StringUtil.EMPTY, values[0]);
        }