如何从URL获取字符串

Question

My application gets most of its data from a php web server.

My problem is when the server return errors. The errors are not HTML pages, but simple strings. for example:

ERROR001

could stand for invalid name.

here is my code:

String responseBody = null;
URL url = new URL(strUrl);
URLConnection connection;
connection = url.openConnection();
connection.setUseCaches(false);
InputStream isResponse = (InputStream) connection.getContent(); // on errors I get IOException here
responseBody = convertStreamToString (isResponse);

When I use it, I get IOException on connection.getContent();

I also tried:

HttpGet getMethod = new HttpGet(url);
String responseBody = null;
responseBody = mClient.execute(getMethod,mResponseHandler); // on errors I getClientProtocolException

but I get getClientProtocolException on mClient.execute

Any ideas how I could read a result like ERROR001 into a string?

Answer 1

The problem is that on error, the Http header is HTTP Error 500 (Internal server error). To read the error content I used the following code:

    String responseBody = null;
    URL url = new URL(strUrl);
    HttpURLConnection connection;
    connection = (HttpURLConnection) url.openConnection();
    connection.setUseCaches(false);
    InputStream isResponse = null;
    try {
        isResponse = connection.getInputStream();
    } catch (IOException e) {
        isResponse = connection.getErrorStream();
    }
    responseBody = convertStreamToString (isResponse);

    return responseBody;

Answer 2

url = new URL(desiredUrl);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
connection.connect();
reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));

Try this one. I think you are not calling the connection.connect() method.

Answer 3

What happens when you use HttpClien? you may want to try this:

String responseBody;

HttpGet request = new HttpGet("your url");
HttpClient client = new DefaultHttpClient();
HttpResponse httpResponse = client.execute(request);
HttpEntity entity = httpResponse.getEntity();

if(entity != null){
    responseBody = convertStreamToString (entity.getContent());
}