java - How to handle network state and HTTP status codes correctly -

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Within one method, I am sending GET and POST requests using HttpURLConnection. As you can see in the example code, I am holding most exceptions. But I wonder if this is the right way and how should I actually manage a site like "no network is available" and bad status code in response to the server? I ask because of this because I want to inform the user about various problems. 

  Public static bitmap getImage (string url) {HttpURLConnection conn = null; {URL new URL} Try new URL (URL); Conn = (HttpURLConnection) newUrl.openConnection (); Conn.setDoInput (true); Conn.setDoOutput (wrong); Conn.setUseCaches (wrong); Conn.setRequestProperty ("Accept-Charset", "utf-8"); Conn.setRequestProperty ("content type", "image / PNG"); Conn.setRequestMethod ("GET"); Conn.connect (); Int total = conn.getContentLength (); InputStream = conn.getInputStream (); // ... read the image here! } Catch (malmarmdureleuxation E) {e.printStackTrace (); Return tap; } Hold (NullPointerException e) {e.printStackTrace (); Return tap; } Hold (IOException e) {e.printStackTrace (); Return tap; } Finally {if (conn! = Null) conn.disconnect (); If (progress! = Null) progress .Set progress (1f); }}   
 
 
 Use this to check whether the network is available or not < / P>   Connectivity Manager Comgad = (Connectivity Manager) context.getSystemService (context.CONNECTIVITY_SERVICE); If (conMgr.getActiveNetworkInfo ()! = Null & amp; conMgr.getActiveNetworkInfo (.) Is available () & amp; amp; amp; conMgr.getActiveNetworkInfo () .isconnected ()) {// connection unavailable} else { // no connection}   
 If the connection is available then you can request http request & amp; Exception .getMessage () returns an appropriate error message that can be displayed to the user if there are any connections errors later.

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