Android retrieve return value from WCF

Question

I have an Android app that posts to a web service via the code below and it all works fine. But the myContract method in the service returns a Boolean, true or false. How do I retrieve that value so I can tell my app to move on or not if false?

HttpPost request = new HttpPost(SERVICE_URI + "/myContract/someString");

request.setHeader("Accept", "application/json");
request.setHeader("Content-type", "application/json");

DefaultHttpClient httpClient = new DefaultHttpClient();
HttpResponse response = httpClient.execute(request);

Edit

Sorry about the edit, but using HttpResponse, and then logging or toasting response.toString() returns a string I don’t understand!

Update

Thanks Shereef,

But that seems like a bit too much information and code to do what I was trying to do. I have added some code below that works but I’m not sure if it’s right. The service will return a Boolean true or false as to whether or not the POST was successful, but I seem to be retrieving it as a string!

HttpEntity responseEntity = response.getEntity();

char[] buffer = new char[(int)responseEntity.getContentLength()];
InputStream stream = responseEntity.getContent();       
InputStreamReader reader = new InputStreamReader(stream);
reader.read(buffer);
stream.close();

JSONObject jsonResponse = new JSONObject(new String(buffer));        
String ServiceResponse = jsonResponse.getString("putCommuniqueResult");

Log.d("WebInvoke", "Saving : " + ServiceResponse);

Is this ok? It works but I’m not sure if its right! Cheers, Mike.

Answer 1

private static String getDataFromXML(final String text) {
    final String temp = new String(text).split("<")[2].split(">")[1];
    final String temp2 = temp.replace("&lt;", "<").replace("&gt;", ">")
            .replace("&amp;", "&");
    return temp2;
}

/**
 * Connects to the web service and returns the pure string returned, NOTE:
 * if the generated url is more than 1024 it automatically delegates to
 * connectPOST
 * 
 * @param hostName
 *            : the host name ex: google.com or IP ex:
 *            127.0.0.1
 * @param webService
 *            : web service name ex: TestWS
 * @param classOrEndPoint
 *            : file or end point ex: CTest
 * @param method
 *            : method being called ex: TestMethod
 * @param parameters
 *            : Array of {String Key, String Value} ex: { { "Username",
 *            "admin" }, { "Password", "313233" } }
 * @return the trimmed String received from the web service
 * 
 * @author Shereef Marzouk - http://shereef.net
 * 
 * 
 */
public static String connectGET(final String hostNameOrIP,
        final String webService, final String classOrEndPoint,
        final String method, final String[][] parameters) {
    String url = "http://" + hostNameOrIP + "/" + webService + "/"
            + classOrEndPoint + "/" + method;
    String params = "";
    if (null != parameters) {
        for (final String[] strings : parameters) {
            if (strings.length == 2) {
                if (params.length() != 0) {
                    params += "&";
                }
                params += strings[0] + "=" + strings[1];
            } else {
                Log.e(Standards.TAG,
                        "The array 'parameters' has the wrong dimensions("
                                + strings.length + ") in " + method + "("
                                + parameters.toString() + ")");
            }
        }
    }
    url += "?" + params;
    if (url.length() >= 1024) { // The URL will be truncated if it is more
                                // than 1024
        return Communications.connectPOST(hostNameOrIP, webService,
                classOrEndPoint, method, parameters);
    }
    final StringBuffer text = new StringBuffer();
    HttpURLConnection conn = null;
    InputStreamReader in = null;
    BufferedReader buff = null;
    try {
        final URL page = new URL(url);
        conn = (HttpURLConnection) page.openConnection();
        conn.connect();
        in = new InputStreamReader((InputStream) conn.getContent());
        buff = new BufferedReader(in);
        String line;
        while (null != (line = buff.readLine()) && !"null".equals(line)) {
            text.append(line + "\n");
        }
    } catch (final Exception e) {
        Log.e(Standards.TAG,
                "Exception while getting " + method + " from " + webService
                        + "/" + classOrEndPoint + " with parameters: "
                        + params + ", exception: " + e.toString()
                        + ", cause: " + e.getCause() + ", message: "
                        + e.getMessage());
        Standards.stackTracePrint(e.getStackTrace(), method);
        return null;
    } finally {
        if (null != buff) {
            try {
                buff.close();
            } catch (final IOException e1) {
            }
            buff = null;
        }
        if (null != in) {
            try {
                in.close();
            } catch (final IOException e1) {
            }
            in = null;
        }
        if (null != conn) {
            conn.disconnect();
            conn = null;
        }
    }

    if (text.length() > 0 && Communications.checkText(text.toString())) {
        final String temp = Communications.getDataFromXML(text.toString());
        Log.i(Standards.TAG, "Success in " + method + "(" + params
                + ") = " + temp);
        return temp;
    }
    Log.w(Standards.TAG, "Warning: " + method + "(" + params + "), text = "
            + text.toString());
    return null;
}

let's say this url makes your service shows it's output

http://google.com/wcfsvc/service.svc/showuserdata/11949

public boolean isWSTrue() {
    String data = connectGET("google.com",
            "wcfsvc", "service.svc",
            "showuserdata/11949", null);
    if(null != data && data.length() >0)
        return data.toLowerCase().contains("true");
    throw new Exception("failed to get webservice data");
}

Note: that within this case you do not actually need to parse the JSON or XML if only checking for boolean then you know if you found true it's true if found anything else it's false.

if you need to get data using XML or JSON you can refer to this answer https://stackoverflow.com/a/3812146/435706