ResponseData responseData = new ResponseData();
        responseData.setUrl("http://example.com");

        ResultData result1 = transformer1.transform(responseData);
        ResultData result2 = transformer2.transform(responseData);
        ResultData result3 = transformer3.transform(responseData);

        assertEquals("transformer1", result1.getTransformerName());
        assertEquals("transformer2", result2.getTransformerName());

        ResponseData responseData = new ResponseData();

        // Transform with different names
        tracker.setName("name1");
        tracker.transform(responseData);

        tracker.setName("name2");
        tracker.transform(responseData);

        tracker.setName("name3");
        tracker.transform(responseData);

        List<String> history = tracker.getNameHistory();

        responseData.setResponseBody(data);
        final ResultData resultData = binaryTransformer.transform(responseData);
        assertEquals("xyz", new String(resultData.getData()));
    }

    public void test_transform_null() {
        try {
            binaryTransformer.transform(null);
            fail();
        } catch (final CrawlerSystemException e) {
            // NOP
        }
    }

 * and retrieving data from access results.
 */
public interface Transformer {

    /**
     * Transforms the given ResponseData into a ResultData.
     *
     * @param responseData the data to be transformed
     * @return the transformed ResultData
     */
    ResultData transform(ResponseData responseData);

    /**
     * Retrieves data from the given AccessResultData object.
     *

        responseData.setMimeType("text/html");
        final ResultData resultData = textTransformer.transform(responseData);
        assertEquals("xyz", new String(resultData.getData(), resultData.getEncoding()));
    }

    public void test_transform_null() {
        try {
            textTransformer.transform(null);
            fail();
        } catch (final CrawlerSystemException e) {
            // NOP
        }

        assertEquals(content, new String(resultData.getData()));
        assertEquals(1, resultData.getChildUrlSet().size());
        assertEquals("http://hoge/test.html?q=hoge", resultData.getChildUrlSet().iterator().next().getUrl());
    }

    public void test_transform_null() {
        try {
            htmlTransformer.transform(null);
            fail();

     */
    public BinaryTransformer() {
        // NOP
    }

    /**
     * Transforms the given ResponseData into a ResultData containing binary content.
     * @param responseData The response data to be transformed.
     * @return The transformed ResultData.
     */
    @Override
    public ResultData transform(final ResponseData responseData) {
        if (responseData == null || !responseData.hasResponseBody()) {

        super();
    }

    /*
     * (non-Javadoc)
     *
     * @see
     * org.codelibs.fess.crawler.transformer.impl.AbstractTransformer#transform(org.fess.crawler.entity.ResponseData)
     */
    @Override
    public ResultData transform(final ResponseData responseData) {
        if (responseData == null || !responseData.hasResponseBody()) {
            throw new CrawlingAccessException("No response body.");

        responseData.setResponseBody(ResourceUtil.getResourceAsFile("extractor/test.xml"), false);
        responseData.setCharSet(Constants.UTF_8);
        final ResultData resultData = xmlTransformer.transform(responseData);
        assertEquals(result, new String(resultData.getData(), Constants.UTF_8));
    }

    public void test_transformNs() throws Exception {
        final String result = "<?xml version=\"1.0\"?>\n"//

        }
    }

    /*
     * (non-Javadoc)
     *
     * @see org.codelibs.fess.crawler.transformer.impl.AbstractTransformer#transform(org.codelibs.fess.crawler.entity.ResponseData)
     */
    @Override
    public ResultData transform(final ResponseData responseData) {
        if (responseData == null || !responseData.hasResponseBody()) {
            throw new CrawlingAccessException("No response body.");