How to Consume Multiple ODATA Services in Native Android(Online) App Using SMP 3.0

[Former Member]

Hi Folks,

Before proceeding on this blog, i would like to thank claudia.pacheco for her wonderful self explanatory blog How to consume OData Services in online Mode (Android) which really helps me in achieving my goal.

As i was proceeding on my app development, i faced a requirement to consume multiple OData services from a single data source. As a newbie on SMP and Android side i faced few challenges in starting to achieve it and tried to find some useful code but hard luck. Later on i got the success. So, thought to share how i implemented hoping it may become useful to other newbie like me.

Prerequisites

• SMP SDK 3.5+ & Android Studio installed on machine
• Added the MAF resources and completed the on boarding of users on SMP 3.0 using MAF logon UI /Core libraries
• Have set the primary back-end point url and created the multiple back-end connections for multiple OData.

Here i'll take an example of read and create operation with two different OData services.

Steps to Achieve

Step 1 : Creating the MultipleOpenListner class which implements the OpenListner as "multipleOpenListner.java"

public class multipleOpenListner implements OpenListner{

//creating multiple listener instance for multiple back-end connections

public static leOpenListner Instance = null, readInstance, createInstance ;

private final CountDownLatch latch = new CountDownLatch(1);

OnlineODataStore store;

Exception error;

public static multipleOpenListner getInstance(String ch){

switch(ch){

case "read":if(readInstance == null){

readInstance = new multipleOpenListner();

Instance = readInstance;

}

break;

case "create":if(createInstance == null){

createInstance = new multipleOpenListner();

Instance = createInstance;

}

break;

  }

return Instance;

}

@Override:

public void storeOpened(OnlineODataStore store){

this.store = store;

latch.countdown();

}

@Override:

public void storeOpenError(ODataException e){

this.error = e;

latch.countDown();

}

public synchronized boolean finished(){

return (store != null || error!=null);

}

public synchronized Exception getError(){

return error;

}

public synchronized OnlineODataStore getStore(){

return store;

}

public void waitForCompletion(){

try{

if(!latch.await(30, TimeUnit.Seconds)){

throw new IllegalStateException("Open listener was not called within 30 seconds");

}

else if(!finished()){

throw new IllegalStateException("Open listener is not in finished state after having completed successfully");

}

}

catch(InterruptedException e){

throw new IllegalStateException("Open Listener waiting for result was interrupted");

}

}

}

Step 2 : Opening OnlineODataStore under the class "OnlineManager.java"

public class OnlineManager {

   public static final String TAG = OnlineManager.class.getSimpleName();

   public static boolean openOnlineStore(Context context, String conCase) throws ODataException{   multipleOpenListner openListener = multipleOpenListner.getInstance(conCase);

   if (openListener.getStore()==null) {

  LogonCoreContext lgCtx = LogonCore.getInstance().getLogonContext();

  IManagerConfigurator configurator = LogonUIFacade.getInstance().getLogonConfigurator(context);

  HttpConversationManager manager = new HttpConversationManager(context);

  configurator.configure(manager);

   //XCSRFTokenRequestFilter implements IRequestFilter  //Request filter that is allowed to preprocess the request before sending   XCSRFTokenRequestFilter requestFilter =

  XCSRFTokenRequestFilter.getInstance(lgCtx);

  XCSRFTokenResponseFilter responseFilter =

  XCSRFTokenResponseFilter.getInstance(context, requestFilter);

  manager.addFilter(requestFilter);

  manager.addFilter(responseFilter);

   try {

  String endPointURL ="";

   switch(conCase){

   case "read": endPointURL = lgCtx.getAppEndPointUrl();

   break;

   case "create": endPointURL = "http://server:8080/backEnd_ConnectionName";

   break;

   default : break;

  }

  URL url = new URL(endPointURL);

   // Method to open a new online store asynchronously   OnlineODataStore.open(context, url, manager, openListener, null);

  openListener.waitForCompletion();

   if (openListener.getError() != null) {

   throw openListener.getError();

  }

  } catch (Exception e) {

   // throw e;   Log.e(TAG, e.getLocalizedMessage(), e);

  }

   //Check if OnlineODataStore opened successfully   OnlineODataStore store = openListener.getStore();

   if (store != null) {

   return true;

  } else {

   return false;

  }

  } else {

   return true;

  }

   //End   }

// Method to read

public static ArrayList read(String conCase) throws ODataException{

  ArrayList<String> arrList = new ArrayList<String>();

  multipleOpenListner openListener = multipleOpenListner.getInstance(conCase);

  OnlineODataStore store = openListener.getStore();

   if (store!=null){

     ODataProperty property;

  ODataPropMap properties;

   try {

   //Executor method for reading an Entity set synchronously   ODataResponseSingle resp = store.executeReadEntitySet("Entity",null);

   //Get the response payload   ODataEntitySet feed = (ODataEntitySet) resp.getPayload();

   //Get the list of ODataEntity   List<ODataEntity> entities = feed.getEntities();

   //Loop to retrieve the information from the response   for (ODataEntity entity: entities){

  properties = entity.getProperties();

  property = properties.get("Property_Name");

  String propName = property.getValue().toString();

  arrList.add(propName);

  }

  } catch (Exception e) {

  Log.e(TAG, e.getLocalizedMessage(), e);

  }

  }

   return arrList;

}

// Method to create

public static void create(UIListener uiListener, String conCase) throws ODataException{   multipleOpenListner openListener = multipleOpenListner.getInstance(conCase);

  OnlineODataStore store = openListener.getStore();

   if(store==null) return;

   try{

  ODataEntity newEntity = createEntity(store);

  RequestListener requestListener = new RequestListener( Operation.Create.getValue(),uiListener);

   //Scheduling method for creating an Entity asynchronously   store.scheduleCreateEntity(newEntity, "cms_Data",

  requestListener, null);

  }

   catch (Exception e){

  e.printStackTrace();

  }

}

public static ODataEntity createEntity(OnlineODataStore store){

  ODataEntity createData = null;

   if(store!= null){

   //If available, it will populates those properties of an OData Entity which are defined by the allocation mode   createData = new ODataEntityDefaultImpl("Model.cms_Data");

   leadData.getProperties().put("Full_Name", new ODataPropertyDefaultImpl("\"Full_Name\"","Deepak Sharma"));

   leadData.getProperties().put("Contact_Number", new ODataPropertyDefaultImpl("\"Contact_Number\"","9810234567"));

    createData.setResourcePath("cms_Data", "cms_Data");

}

return createData;

}

}

Step 3 : Call openOnlineStore method from your MAFLogon Activity class.

try {

  OnlineManager.openOnlineStore(this,"read");

} catch (ODataException e) {

  e.printStackTrace();

}

Step 4 : Call read and create methods from activity class wherever required with openOnlineStore method.

try {

   OnlineManager.openOnlineStore(this,"create");

   OnlineManager.create(this, "create");

} catch (ODataException e) {

  e.printStackTrace();

}

Hope it helps!!! :smile: