*
 * <pre>
 * XpathTransformer transformer = new XpathTransformer();
 * transformer.addFieldRule("title", "//title/text()");
 * transformer.addFieldRule("body", "//body/p/text()");
 *
 * ResponseData responseData = new ResponseData();
 * responseData.setBody(new ByteArrayInputStream("&lt;html&gt;&lt;head&gt;&lt;title&gt;Example&lt;/title&gt;&lt;/head&gt;&lt;body&gt;&lt;p&gt;Hello World&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;".getBytes()));

 * <p>
 * The extracted text is obtained from the nodes selected by the {@code targetNodePath} XPath expression.
 * The default value for {@code targetNodePath} is "//HTML/BODY | //@alt | //@title", which selects the body of the HTML document,
 * as well as the alt and title attributes.
 * </p>
 * <p>
 * The class uses {@link DOMParser} to parse HTML documents and {@link XPathAPI} to execute XPath queries.

        Term term1 = new Term("content", "test");
        Term term2 = new Term("title", "query");
        builder.add(new TermQuery(term1), BooleanClause.Occur.SHOULD);
        builder.add(new TermQuery(term2), BooleanClause.Occur.SHOULD);
        BooleanQuery booleanQuery = builder.build();

        String[] fields = { "content", "title" };
        List<TermQuery> queryList = SuggestUtil.getTermQueryList(booleanQuery, fields);

 * Example Usage:
 * </p>
 *
 * <pre>
 * XmlTransformer transformer = new XmlTransformer();
 * transformer.setNamespaceAware(true);
 * transformer.setCacheDuration(30);
 * transformer.addFieldRule("title", "/book/title/text()");
 * transformer.addFieldRule("author", "/book/author/name/text()");
 *
 * ResponseData responseData = new ResponseData();

    .setTags(new String[]{"category"})      // filter by tags
    .setRoles(new String[]{"user"})         // filter by roles  
    .setLanguages(new String[]{"en", "ja"}) // language preference
    .setFields(new String[]{"title"})       // search specific fields
    .execute()
    .getResponse();
```

## Project Structure

```
src/
├── main/java/org/codelibs/fess/suggest/

        assertNotNull(tokensContent);
        assertEquals(2, tokensContent.size());

        List<AnalyzeToken> tokensTitle = analyzer.analyze(text, "title", lang);
        assertNotNull(tokensTitle);
        assertEquals(2, tokensTitle.size());

        // Test with null field
        List<AnalyzeToken> tokensNull = analyzer.analyze(text, null, lang);