关于使用itext转Html为pdf添加css样式的问题

package com.test;import java.io.ByteArrayInputStream;import java.io.ByteArrayOutputStream;import java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.InputStream;import com.itextpdf.text.Document;import com.itextpdf.text.pdf.PdfWriter;import com.itextpdf.tool.xml.XMLWorkerHelper;public class Html2Pdf{ ???public static void main(String [] args) throws Exception ???{ ???String urlsource = getURLSource(new File("D:/test.html")); ???String cssSource = getURLSource(new File("D:/css.css")); ???htmlToPdf(urlsource,cssSource); ???} ???// 支持中文 ???public static void htmlToPdf(String htmlstr,String cssSource) throws Exception ???{ ???String outputFile = "D:/test.pdf"; ???Document document = new Document(); ???PdfWriter writer = null; ???writer = PdfWriter.getInstance(document, new FileOutputStream(outputFile)); ???document.open(); ???????InputStream bis = new ByteArrayInputStream(htmlstr.toString().getBytes());
 ???InputStream cssis = new ByteArrayInputStream(cssSource.toString().getBytes());

      XMLWorkerHelper.getInstance().parseXHtml(writer, document, bis,cssis);

 ???document.close(); ???} ???/** ????* 通过网站域名URL获取该网站的源码 ????* ?????* @param url ????* @return String ????* @throws Exception ????*/ ???public static String getURLSource(File url) throws Exception ???{ ???InputStream inStream = new FileInputStream(url); ???// 通过输入流获取html二进制数据 ???byte [] data = readInputStream(inStream); // 把二进制数据转化为byte字节数据 ???String htmlSource = new String(data); ???inStream.close(); ???return htmlSource; ???} ???/** ????* 把二进制流转化为byte字节数组 ????* ?????* @param instream ????* @return byte[] ????* @throws Exception ????*/ ???public static byte [] readInputStream(InputStream instream) throws Exception ???{ ???ByteArrayOutputStream outStream = new ByteArrayOutputStream(); ???byte [] buffer = new byte[1204]; ???int len = 0; ???while ((len = instream.read(buffer)) != -1) ???{ ???????outStream.write(buffer, 0, len); ???} ???instream.close(); ???return outStream.toByteArray(); ???}}