public static String uncompress(String str) throws IOException {
	    if (str == null || str.length() == 0) {
	      return str;
	    }
	    ByteArrayOutputStream out = new ByteArrayOutputStream();
	    ByteArrayInputStream in = new ByteArrayInputStream(str
	        .getBytes("ISO-8859-1"));
	    GZIPInputStream gunzip = new GZIPInputStream(in);
	    byte[] buffer = new byte[256];
	    int n;
	    while ((n = gunzip.read(buffer)) >= 0) {
	      out.write(buffer, 0, n);
	    }
	    // toString()使用平台默认编码，也可以显式的指定如toString("GBK")
	    return out.toString();
	  }