wap代码 html过滤器(java)

//--新增wap代码
//过滤器
public static String filter(String str)
 {
  String s1 = str;
  s1 = s1.replaceAll("(</p>)|</P>","<br>");
  s1 = s1.replaceAll("(</div>)|</DIV>","<br>");
  try
  {
    //Pattern pattern=Pattern.compile("<[^<|^>]*>");
    Pattern pattern=Pattern.compile("(<[^<|^>]*>)|(\\{[^\\{|^\\}]*\\})",Pattern.CASE_INSENSITIVE);
          Matcher matcher=pattern.matcher(s1);
          StringBuffer txt=new StringBuffer();
          while(matcher.find())
          {
              String group=matcher.group();
              if(group.matches("<[ \\s]*>"))
              {
                  matcher.appendReplacement(txt,group);    
              }
              else
              {
                  if(group.matches("<(IMG|img) [^<|^>]*>")) //判断是img标签
      {
   if(group.indexOf("_wap")==-1){//2008-8-19
       group = group.substring(0,group.lastIndexOf("."))+"_wap"+group.substring(group.lastIndexOf("."),group.length()).toLowerCase();
   }
   if(group.indexOf("bmp")!=-1){
group=group.replaceAll("_wap","");
  }