正则表达式分析网页有关问题

package com.glht.search.action;import java.io.BufferedInputStream;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.net.MalformedURLException;import java.net.URL;import java.util.regex.Matcher;import java.util.regex.Pattern;public class Ask {    /**     * @param args     */    public static void main(String[] args) {getSuNing("http://www.suning.com/webapp/wcs/stores/servlet/odeSearch?storeId=10052&catalogId=10051&categoryId=20394&langId=-7&suggestionWordList=%5b%5d&isCatalogSearch=1&isList=0&sortType=0&currentPage=0");        getSuNing("http://www.suning.com/webapp/wcs/stores/servlet/odeSearch?storeId=10052&catalogId=10051&categoryId=20321&langId=-7&suggestionWordList=%5b%5d&isCatalogSearch=1&isList=0&sortType=0&currentPage=0");    }    /*     * 获取苏宁的一个分类页面的产品     */    public static void getSuNing(String url) {        String content = Utils.getURLContent(url, "utf-8");        System.out.println("内容获取完成");        StringBuilder regStr = new StringBuilder();        regStr.append("class=\"pro_img\".*?");        regStr.append("<a.*?href=\"(.*?)\"");        regStr.append(".*?src=\"(.*?)\".*?alt=\"(.*?)\"");        regStr.append(".*?<em>(\\d+.?\\d+)</em>");        Pattern pattern = Pattern.compile(regStr.toString(), Pattern.DOTALL);        Matcher matcher = pattern.matcher(content);        int count = 0;        while (matcher.find()) {            System.out.println("第" + (++count) + "个");        }        System.out.println("分析完成=========");    }    /*     * 获取页面的内容     */    public static String getURLContent(String url, String encoding) {        if (url == null || "".equals(url.trim()))            return null;        StringBuffer content = new StringBuffer();        try {            // 新建URL对象            URL u = new URL(url);            InputStream in = new BufferedInputStream(u.openStream());            InputStreamReader theHTML = new InputStreamReader(in,                    encoding != null ? encoding : "gb2312");            int c;            while ((c = theHTML.read()) != -1) {                content.append((char) c);            }        }        // 处理异常        catch (MalformedURLException e) {            System.err.println(e);        } catch (IOException e) {            System.err.println(e);        }        return content.toString();    }}