public void test_metaDataOperations() {
        // Test metadata operations
        ResponseData data = new ResponseData();

        // Add metadata
        data.addMetaData("key1", "value1");
        data.addMetaData("key2", 123);
        data.addMetaData("key3", true);

        Map<String, Object> metaDataMap = data.getMetaDataMap();
        assertNotNull(metaDataMap);
        assertEquals(3, metaDataMap.size());

                if (owner != null) {
                    responseData.addMetaData(FS_FILE_USER, owner.getName());
                }
            }

            final AclFileAttributeView aclFileAttributeView = Files.getFileAttributeView(file.toPath(), AclFileAttributeView.class);
            if (aclFileAttributeView != null) {
                responseData.addMetaData(FILE_ATTRIBUTE_VIEW, aclFileAttributeView);

                    processAllowedSIDs(file, ace.getSID(), ace.isAllow() ? sidAllowSet : sidDenySet);
                }
                responseData.addMetaData(SMB_ALLOWED_SID_ENTRIES, sidAllowSet.toArray(new SID[sidAllowSet.size()]));
                responseData.addMetaData(SMB_DENIED_SID_ENTRIES, sidDenySet.toArray(new SID[sidDenySet.size()]));
            }
        } catch (final IOException e) {

                    processAllowedSIDs(file, ace.getSID(), ace.isAllow() ? sidAllowSet : sidDenySet);
                }
                responseData.addMetaData(SMB_ALLOWED_SID_ENTRIES, sidAllowSet.toArray(new SID[sidAllowSet.size()]));
                responseData.addMetaData(SMB_DENIED_SID_ENTRIES, sidDenySet.toArray(new SID[sidDenySet.size()]));
            }
        } catch (final IOException e) {

        NullResponseProcessor processor = new NullResponseProcessor();
        ResponseData responseData = new ResponseData();

        responseData.addMetaData("key1", "value1");
        responseData.addMetaData("key2", 123);

        // Execute - should not throw any exception
        processor.process(responseData);

        // Verify metadata is unchanged

            addMetadata(extractData, key, value);
        }
    }

    /**
     * Adds metadata to the extraction data if the value is not null.
     * @param extractData the extraction data
     * @param name the metadata name
     * @param value the metadata value
     */
    protected void addMetadata(final ExtractData extractData, final String name, final String value) {

            responseData.setMimeType(statObject.contentType());
            statObject.headers().forEach(e -> responseData.addMetaData(e.getFirst(), e.getSecond()));

            if (contentLengthHelper != null) {
                final long maxLength = contentLengthHelper.getMaxLength(responseData.getMimeType());

            responseData.setMimeType(headObject.contentType());

            // Add metadata
            if (headObject.metadata() != null) {
                headObject.metadata().forEach(responseData::addMetaData);
            }

            if (contentLengthHelper != null) {
                final long maxLength = contentLengthHelper.getMaxLength(responseData.getMimeType());

                final Map<String, String> blobMetadata = blob.getMetadata();
                if (blobMetadata != null) {
                    blobMetadata.forEach(responseData::addMetaData);
                }
                if (blob.getSize() < maxCachedContentSize) {
                    try (InputStream contentStream = new BufferedInputStream(Channels.newInputStream(blob.reader()))) {

            checkMaxContentLength(responseData);

            if (file.getUser() != null) {
                responseData.addMetaData(FTP_FILE_USER, file.getUser());
            }
            if (file.getGroup() != null) {
                responseData.addMetaData(FTP_FILE_GROUP, file.getGroup());
            }

            if (includeContent) {
                File tempFile = null;