How to catch the Exception in Retrofit android

Question

1. I have defined the classes as below.
2. I have used dagger with Retrofit here

What I am trying to do::

I am trying to catch t

Answer 1

As I know, there is no internet connection the RetrofitError contains a ConnectionException as the cause.

public class RetrofitErrorHandler implements ErrorHandler {

    @Override
    public Throwable handleError(RetrofitError cause) {
        if (cause.isNetworkError()) {
            if (cause.getCause() instanceof SocketTimeoutException) {
                  /* your code here*/ 
                return new MyConnectionTimeoutException();
            } else {
                /* your code here*/
                return new MyNoConnectionException();
            }
        } else {
            //Do whatever you want to do if there is not a network error.  
        }
    }
}

Or you can create a custom Retrofit client that checks for connectivity before executing a request and throws an exception.

public class ConnectivityCheck implements Client {

    Logger log = LoggerFactory.getLogger(ConnectivityCheck.class);

    public ConnectivityCheck (Client wrappedClient, NetworkConnectivityManager ncm) {
        this.wrappedClient = wrappedClient;
        this.ncm = ncm;
    }

    Client wrappedClient;
    private NetworkConnectivityManager ncm;

    @Override
    public Response execute(Request request) throws IOException {
        if (!ncm.isConnected()) {
            log.debug("No connectivity %s ", request);
            throw new NoConnectivityException("No connectivity");
        }
        return wrappedClient.execute(request);
    }
}

and then use it when configuring RestAdapter

RestAdapter.Builder().setEndpoint(serverHost)
                     .setClient(new ConnectivityCheck(new OkHttpClient(), ...))

Answer 2

As far as I know, I don't think Retrofit supports 'connectivity checking in call time' and I don't think that is exactly what you want.

Try to check connectivity before your call, for example,

private void sendData() {
    if( isConnected ) {
          switch(call) {
               case "userSignIn":
                      Call !
                      break;
               ...
    }
}

Maybe you can check this solution too