Java Language HttpURLConnection Get response body from a URL as a String
Example
String getText(String url) throws IOException {
HttpURLConnection connection = (HttpURLConnection) new URL(url).openConnection();
//add headers to the connection, or check the status if desired..
// handle error response code it occurs
int responseCode = conn.getResponseCode();
InputStream inputStream;
if (200 <= responseCode && responseCode <= 299) {
inputStream = connection.getInputStream();
} else {
inputStream = connection.getErrorStream();
}
BufferedReader in = new BufferedReader(
new InputStreamReader(
inputStream));
StringBuilder response = new StringBuilder();
String currentLine;
while ((currentLine = in.readLine()) != null)
response.append(currentLine);
in.close();
return response.toString();
}
This will download text data from the specified URL, and return it as a String.
How this works:
-
First, we create a
HttpUrlConnectionfrom our URL, withnew URL(url).openConnection(). We cast theUrlConnectionthis returns to aHttpUrlConnection, so we have access to things like adding headers (such as User Agent), or checking the response code. (This example does not do that, but it's easy to add.) -
Then, create
InputStreambasing on the response code (for error handling) -
Then, create a
BufferedReaderwhich allows us to read text fromInputStreamwe get from the connection. -
Now, we append the text to a
StringBuilder, line by line. -
Close the
InputStream, and return the String we now have.
Notes:
-
This method will throw an
IoExceptionin case of failure (such as a network error, or no internet connection), and it will also throw an uncheckedMalformedUrlExceptionif the given URL is not valid. -
It can be used for reading from any URL which returns text, such as webpages (HTML), REST APIs which return JSON or XML, etc.
-
See also: Read URL to String in few lines of Java code.
Usage:
Is very simple:
String text = getText(”http://example.com");
//Do something with the text from example.com, in this case the HTML.
