java.io.IOException: Server returned HTTP response

2020-02-08 16:25发布

问题:

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.

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

The code:

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();

The Exception:

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)

What's wrong? Did the host block me?

回答1:

HTTP status code 500 usually means that the webserver code has crashed. You need to determine the status code beforehand using HttpURLConnection#getResponseCode() and in case of errors, read the HttpURLConnection#getErrorStream() instead. It may namely contain information about the problem.

If the host has blocked you, you would rather have gotten a 4nn status code like 401 or 403.

See also:

  • How to use URLConnection to fire and handle HTTP requests?


回答2:

This Status Code 500 is an Internal Server Error. This code indicates that a part of the server (for example, a CGI program) has crashed or encountered a configuration error.

i think the problem does'nt lie on your side, but rather on the side of the Http server. the resources you used to access may have been moved or get corrupted, or its configuration just may have altered or spoiled



回答3:

I have encountered the same problem and found out the solution.

You may look within the first server response and see if the server sent you a cookie.

To check if the server sent you a cookie, you can use HttpURLConnection#getHeaderFields() and look for headers named "Set-Cookie".

If existing, here's the solution for your problem. 100% Working for this case!

+1 if it worked for you.



回答4:

I had this problem i.e. works fine when pasted into browser but 505s when done through java. It was simply the spaces that needed to be escaped/encoded.



回答5:

The problem must be with the parameters you are passing(You must be passing blank parameters). For example : http://www.myurl.com?id=5&name= Check if you are handling this at the server you are calling.



回答6:

Change the content-type to "application/x-www-form-urlencoded", i solved the problem.