Consuming a web service in an android application

Question

I am trying to consume a web service that I created locally from an Android application. My problem is that in my Android app, at a certain point, I have to give an URL with parameters that looks like this : http://localhost:8080/CalculatorApp/CalculatorWSService/add?i=1&j=1

where CalculatorWS is the web service I use, add is the operation in it and i and j are parameters of add operation. For now I am using a sample app Calculator (from NetBeans) for testing and I want to retrieve the correct URL to give to my web service client (Android app) so it can give me back an XML to parse.

I tried to use that URL mentioned above but it doesn't work.

Does anybody know what is the correct URL to put ?

Answer 1

Use this URL:

http://10.0.2.2:8080/CalculatorApp/CalculatorWSService/add?i=1&j=1

Since Android emulator run on Virtual Machine therefore we have to use this IP address instead of localhost or 127.0.0.1

Answer 2

you need to set URL as 10.0.2.2:portNr

portNr = the given port by ASP.NET Development Server my current service is running on localhost:3229/Service.svc

so my url is 10.0.2.2:3229

i'd fixed my problem this way

i hope it helps...

Answer 3

sharktiger like you says on the comments, i'll paste here some code to help you to figure how to proced, this code try to connect to a web service and parse the InputStream retrieved, just like @Vikas Patidar and @MisterSquonk says, you must configure the url in the android code like them explain. So, i post my code

and example of call to HttpUtils...

public static final String WS_BASE = "http://www.xxxxxx.com/dev/xxx/";
public static final String WS_STANDARD = WS_BASE + "webserviceoperations.php";
public static final String REQUEST_ENCODING = "iso-8859-1";

    /**
         * Send a request to the servers and retrieve InputStream
         * 
         * @throws AppException
         */
        public static Login logToServer(Login loginData) {
            Login result = new Login();
            try {
                // 1. Build XML
                byte[] xml = LoginDAO.generateXML(loginData);
                // 2. Connect to server and retrieve data
                InputStream is = HTTPUtils.readHTTPContents(WS_STANDARD, "POST", xml, REQUEST_ENCODING, null);
                // 3. Parse and get Bean
                result = LoginDAO.getFromXML(is, loginData);
            } catch (Exception e) {
                result.setStatus(new ConnectionStatus(GenericDAO.STATUS_ERROR, MessageConstants.MSG_ERROR_CONNECTION_UNKNOWN));

            }
            return result;
        }

and the method readHTTPContents from my class HTTPUtils

/**
     * Get the InputStream contents for a specific URL request, with parameters.
     * Uses POST. PLEASE NOTE: You should NOT use this method in the main
     * thread.
     * 
     * @param url
     *            is the URL to query
     * @param parameters
     *            is a Vector with instances of String containing the parameters
     */
    public static InputStream readHTTPContents(String url, String requestMethod, byte[] bodyData, String bodyEncoding, Map<String, String> parameters)
            throws AppException {
        HttpURLConnection connection = null;
        InputStream is = null;
        try {
            URL urlObj = new URL(url);
            if (urlObj.getProtocol().toLowerCase().equals("https")) {
                trustAllHosts();
                HttpsURLConnection https = (HttpsURLConnection) urlObj
                        .openConnection();
                https.setHostnameVerifier(new HostnameVerifier() {
                    public boolean verify(String hostname, SSLSession session) {
                        return true;
                    }
                });
                connection = https;
            } else {
                connection = (HttpURLConnection) urlObj.openConnection();
            }
            // Allow input
            connection.setDoInput(true);
            // If there's data, prepare to send.
            if (bodyData != null) {
                connection.setDoOutput(true);
            }
            // Write additional parameters if any
            if (parameters != null) {
                Iterator<String> i = parameters.keySet().iterator();
                while (i.hasNext()) {
                    String key = i.next();
                    connection.addRequestProperty(key, parameters.get(key));
                }
            }
            // Sets request method
            connection.setRequestMethod(requestMethod);
            // Establish connection
            connection.connect();
            // Send data if any

            if (bodyData != null) {
                OutputStream os = connection.getOutputStream();
                os.write(bodyData);
            }
            if (connection.getResponseCode() != HttpURLConnection.HTTP_OK) {
                throw new AppException("Error HTTP code " + connection.getResponseCode());
            }
            is = connection.getInputStream();
            int numBytes = is.available();
            if (numBytes <= 0) {
                closeInputStream(is);
                connection.disconnect();
                throw new AppException(MessageConstants.MSG_ERROR_CONNECTION_UNKNOWN);
            }

            ByteArrayOutputStream content = new ByteArrayOutputStream();

            // Read response into a buffered stream
            int readBytes = 0;
            while ((readBytes = is.read(sBuffer)) != -1) {
                content.write(sBuffer, 0, readBytes);
            }
            ByteArrayInputStream byteStream = new ByteArrayInputStream(content.toByteArray());
            content.flush();
            return byteStream;
        } catch (Exception e) {
//          Logger.logDebug(e.getMessage());
            throw new AppException(e.getMessage());
        } finally {
            closeInputStream(is);
            closeHttpConnection(connection);
        }
    }

Hope this help you...

Answer 4

If you're using an emulator then read below paragraph taken from: Referring to localhost from the emulated environment

If you need to refer to your host computer's localhost, such as when you want the emulator client to contact a server running on the same host, use the alias 10.0.2.2 to refer to the host computer's loopback interface. From the emulator's perspective, localhost (127.0.0.1) refers to its own loopback interface.