/**
     * 得到網頁中圖片的地址
     * @param htmlStr html字串
     * @return List<String>
     */
    private  List<String> getImgStr(String htmlStr) {
        List<String> pics = new ArrayList<String>();
        String img = "";
        Pattern p_image;
        Matcher m_image;
        String regEx_img = "<img.*src\\s*=\\s*(.*?)[^>]*?>"
 
;
        p_image = Pattern.compile(regEx_img, Pattern.CASE_INSENSITIVE);
        m_image = p_image.matcher(htmlStr);
        while (m_image.find()) {
            // 得到<img />資料
            img = m_image.group();
            // 匹配<img>中的src資料
            Matcher m = Pattern.compile("src\\s*=\\s*\"?(.*?)(\"|>|\\s+)"
 
).matcher(img);
            while (m.find()) {
                pics.add(m.group(1));
            }
        }
        return pics;
    }