com.konylabs.middleware.customconflict

Interface CustomConflictResolver

public interface CustomConflictResolver

Use this interface to implement custom logic for resolving data conflict during upload of offline objects.

Conflict arises when the data at the server has been changed after the data is downloaded by the client.

Upon each upload, the Server makes a get call to fetch the data corresponding to primary key being uploaded. It calculates the checksum out of the data and compares with the checksum of the to be uploaded data. If both have same checksum, then there is no conflict. If there is a checksum change then conflict is marked. Based on the action of client data and the action of server data, the corresponding method is called to handle particular conflict. For each conflict type, refer to method level comments.

The required information can be accessed from ConflictContext and the ConflictResolutionResult has to be returned with proper actionType and submitToServer.

The ActionType set for ConflictResolutionResult should be the supported operation on the object and should be acceptable on the current state

If the implementation returns null ConflictResolutionResult then flow continues as if there is no conflict. If conflictResolutionResult submitToServer is false, then the server data and action is returned to client, irrespective of what has been set in the conflictResult to ensure proper replica of server data on client ConflictResolutionResult

 
  if (conflictcontext.getObjectId().equals("categories")) {
      if (clientData.get("CategoryID").getAsInt() == 4) {
        JsonObject resolvedData = getResolvedData(serverData, conflictContext);
        conflictResult = new ConflictResolutionResult(resolvedData, ActionType.update, true);
      } else {
        if (clientData.get("CategoryID").getAsInt() == 3) {
          clientData.addProperty("CategoryName", serverData.get("CategoryName").getAsString());
        }
        conflictResult = new ConflictResolutionResult(clientData, ActionType.update, true);
      }
    }
 

Since:

Fabric V8 SP3 (8.3)

See Also:

ConflictContext, ConflictResolutionResult

Method Summary

Modifier and Type	Method and Description
ConflictResolutionResult	resolveClientCreateServerExists(com.google.gson.JsonObject clientData, com.google.gson.JsonObject serverData, ConflictContext conflictContext) This method is used to represent the create conflict, i.e when client creates and the record with same primary key exists on server.
ConflictResolutionResult	resolveClientDeleteServerUpdate(com.google.gson.JsonObject clientData, com.google.gson.JsonObject serverData, ConflictContext conflictContext) This method is used to represent the delete conflict, i.e when client deletes and record with same primary key on server is updated.
ConflictResolutionResult	resolveClientUpdateServerDelete(com.google.gson.JsonObject clientData, com.google.gson.JsonObject serverData, ConflictContext conflictContext) This method is used to represent the update conflict with delete, i.e when client update and record with same primary key on server is either soft deleted or hard deleted.
ConflictResolutionResult	resolveClientUpdateServerUpdate(com.google.gson.JsonObject clientData, com.google.gson.JsonObject serverData, ConflictContext conflictContext) This method is used to represent the update conflict, i.e when client update and record with same primary key on server is updated post download.

Method Detail

resolveClientCreateServerExists

ConflictResolutionResult resolveClientCreateServerExists(com.google.gson.JsonObject clientData,
                                                         com.google.gson.JsonObject serverData,
                                                         ConflictContext conflictContext)

This method is used to represent the create conflict, i.e when client creates and the record with same primary key exists on server. Create conflict is applicable only for non auto generated PK

Parameters:

clientData - Holds the data from client side

serverData - Holds the data from server side

conflictContext - Holds the accessible meta information

Returns:

The resolved conflictResult or if null is returned then flow continues as if there is no conflict

resolveClientUpdateServerUpdate

ConflictResolutionResult resolveClientUpdateServerUpdate(com.google.gson.JsonObject clientData,
                                                         com.google.gson.JsonObject serverData,
                                                         ConflictContext conflictContext)

This method is used to represent the update conflict, i.e when client update and record with same primary key on server is updated post download.

Parameters:

clientData - Holds the data from client side

serverData - Holds the data from server side

conflictContext - Holds the accessible meta information

Returns:

The resolved conflictResult or if null is returned then flow continues as if there is no conflict

resolveClientUpdateServerDelete

ConflictResolutionResult resolveClientUpdateServerDelete(com.google.gson.JsonObject clientData,
                                                         com.google.gson.JsonObject serverData,
                                                         ConflictContext conflictContext)

This method is used to represent the update conflict with delete, i.e when client update and record with same primary key on server is either soft deleted or hard deleted.

Parameters:

clientData - Holds the data from client side

serverData - Holds the data from server side

conflictContext - Holds the accessible meta information

Returns:

The resolved conflictResult or if null is returned then flow continues as if there is no conflict

resolveClientDeleteServerUpdate

ConflictResolutionResult resolveClientDeleteServerUpdate(com.google.gson.JsonObject clientData,
                                                         com.google.gson.JsonObject serverData,
                                                         ConflictContext conflictContext)

This method is used to represent the delete conflict, i.e when client deletes and record with same primary key on server is updated.

Parameters:

clientData - Holds the data from client side

serverData - Holds the data from server side

conflictContext - Holds the accessible meta information

Returns:

The resolved conflictResult or if null is returned then flow continues as if there is no conflict