过滤特殊字符跟乱码

过滤特殊字符和乱码
public static final String chopWhitespace(String str) {
  if(null==str || "".equals(str))return "";

  StringBuilder sb = new StringBuilder("");
  for (int i = 0; i < str.length(); i++) {
   char ch = str.charAt(i);
   int ci = ch;
   //System.out.println(ch+" "+ci);
   if (9 == ci || 10 == ci || 13 == ci || 32 <= ci && !Character.isISOControl(ci)) {
    sb.append(ch);
   }
  }
  return sb.toString();
}