java.io.IOException：服务器返回HTTP响应代码：500

我正在使用Java来解决这个问题。我想从URL获取一些HTML信息。这段代码工作了很长时间，但突然间，它停止了工作。

I'm facing this problem with Java. I want to get some HTML informations from a URL. This code was working for so long, but suddenly, it stopped working.

当我使用浏览器访问此URL时，它打开没有问题。

When I access this URL using the browser, it opens with no problem.

代码：

URL site = new URL(this.url);
java.net.URLConnection yc = site.openConnection();
BufferedReader in = new BufferedReader(new InputStreamReader(yc.getInputStream()));
String inputLine;
String objetivo = "<td height=\"28\" colspan=\"2\"";
while ((inputLine = in.readLine()) != null && !inputLine.contains(objetivo)) {
}
inputLine = in.readLine();

例外：

java.io.IOException: Server returned HTTP response code: 500 for URL: http://www.myurl.com
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
    at Sites.websites.Site1.getData(Site1.java:53)
    at util.Util.lerArquivo(Util.java:278)
    at util.Util.main(Util.java:983)

出了什么问题？主持人阻止了我吗？

What's wrong? Did the host block me?