throw exceptionSet.iterator().next();
            }
            writer.flush();
            final ExtractData extractData = new ExtractData(writer.toString());
            extractMetadata(document, extractData);
            return extractData;
        } catch (final Exception e) {
            throw new ExtractException(e);
        }
    }

    /**

        final ExtractData extractData = markdownExtractor.getText(in, null);
        CloseableUtil.closeQuietly(in);

        // Verify front matter metadata
        final String[] titles = extractData.getValues("frontmatter.title");
        assertNotNull(titles);
        assertEquals("Sample Markdown Document", titles[0]);

        final String[] authors = extractData.getValues("frontmatter.author");

     * @param params The parameters map, expected to contain ExtractData.RESOURCE_NAME_KEY
     * @return An ExtractData object containing the filename as content, or empty string if not found
     * @throws CrawlerSystemException if the input stream is null
     * @throws ExtractException if an unexpected error occurs during extraction
     */
    @Override
    public ExtractData getText(final InputStream in, final Map<String, String> params) {

    }

    public void test_usingPredefinedConstants() {
        // Test using predefined constants
        ExtractData data = new ExtractData();

        data.putValue(ExtractData.RESOURCE_NAME_KEY, "test.pdf");
        data.putValue(ExtractData.URL, "https://example.com/test.pdf");
        data.putValues(ExtractData.FILE_PASSWORDS, new String[] { "pass1", "pass2" });

            if (getLogger().isDebugEnabled()) {
                getLogger().debug("ExtractData: {}", extractData);
            }
            // meta
            extractData.getKeySet().stream().filter(k -> extractData.getValues(k) != null).forEach(key -> {
                final String[] values = extractData.getValues(key);
                metaDataMap.put(key, values);

                // meta -> content

import java.io.IOException;
import java.io.InputStream;
import java.util.Map;

import org.apache.poi.hdgf.extractor.VisioTextExtractor;
import org.codelibs.fess.crawler.entity.ExtractData;
import org.codelibs.fess.crawler.exception.CrawlerSystemException;
import org.codelibs.fess.crawler.exception.ExtractException;

/**
 * Gets a text from . file.
 *
 * @author shinsuke
 *
 */

        final InputStream in = new ByteArrayInputStream(new byte[0]);
        final Map<String, String> params = new HashMap<>();
        params.put(ExtractData.RESOURCE_NAME_KEY, "test-document.pdf");

        final ExtractData result = filenameExtractor.getText(in, params);

        assertNotNull(result);
        assertEquals("test-document.pdf", result.getContent());
    }

    /**

            final ExtractData extractData = new ExtractData(plainText);

            // Extract front matter metadata
            if (extractFrontMatter) {
                extractFrontMatterMetadata(document, extractData);
            }

            // Extract headings
            if (extractHeadings) {
                extractHeadingMetadata(document, extractData);
            }

            final ExtractData extractData = new ExtractData(textBuilder.toString().trim());

            if (extractMetadata) {
                for (final Map.Entry<String, List<String>> entry : metadataMap.entrySet()) {
                    final List<String> values = entry.getValue();
                    extractData.putValues(entry.getKey(), values.toArray(new String[0]));
                }

            throw new ExtractException(e);
        }
    }

    /**
     * Creates an ExtractData object from the extracted content.
     * @param content The extracted content.
     * @return The ExtractData object.
     */
    protected ExtractData createExtractData(final String content) {
        return new ExtractData(extractString(content));
    }

    /**
     * Detects the encoding of the input stream.