This presentation discusses how you can implement various data caching and synching strategies using Oracle MAF and the A-Team Mobile Persistence Accelerator (AMPA). AMPA is an open source lightweight persistence and data synchronization framework that works on top of Oracle Mobile Application Framework (MAF). It eases the consumption of RESTful services, and provides a complete persistence layer that allows you to use the mobile application in offline mode. You can read and write data while not connected to the internet, and synchronize any pending data changes later when you are online again. The AMPA design-time wizards that are integrated with JDeveloper enable you to build a fully functional mobile application within minutes.

1. Implementing Data Caching
and Data Syncing using
Oracle Mobile Application
Framework (MAF)
Steven Davelaar
Oracle Mobile A-Team
Oracle Corporation
@stevendavelaar
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2. Agenda
Quick Intro to Oracle MAF
Designing a Mobile-Optimized API
– On-demand loading versus data caching
Using A-Team Mobile Persistence Accelerator
– Implementing Data Caching
– Implementing Data Syncing
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3. Oracle Mobile Application Framework
Productivity boosting mobile development framework
Build Once, Run on Multiple-Platforms
Simpler UI development
Java, JavaScript, and HTML5-based
application development
Choice of development tools
Offline-capable: SQLite with Encryption
Full Access to Native Device Features
Modular, Reusable Components
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4. Business Logic Development
Access and Process Application Data
Code logic with Java
Lightweight JVM
Native library on device
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5. UI Implementation Options in Oracle MAF
Component based page definition
– AMX Components
Programmatic HTML5
– with any third-party HTML5 frameworks
Remote URL
– Any server-side HTML
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6. Extend and Expand
Add capabilities to the framework
Cordova Plug-in Support
– Add functionality such as barcode scanning,
NFC, geo-fencing, etc.
– Cross platform
Custom AMX Component Support
– Allows developer to add custom UI
components to the framework
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7. Oracle MAF Architecture
Device Native Container
HTML5 JavaScript Presentation
PhoneGap/
Cordova
Device
Services
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Web
View
Server
HTML
ADF Mobile
AMX View
Oracle IDM
Oracle IAM
Third Party
Web Sites
Server or Cloud
backend
Mobile
Device
Local
HTML
Configuration
Server
ADF Controller
Credential Management,
SSO Access Control
App
Config
Server
SOAP REST
Web Services
Java VM
Business
Logic
ADF Model
Encrypted
SQLite DB
JDBC
SQLite

8. Oracle MAF Architecture
Device Native Container
HTML5 JavaScript Presentation
PhoneGap/
Cordova
Device
Services
Copyright © 2013, Oracle and/or its affiliates. All 8 rights reserved.
Web
View
Server
HTML
ADF Mobile
AMX View
Oracle IDM
Oracle IAM
Third Party
Web Sites
Server or Cloud
backend
Mobile
Device
Local
HTML
Configuration
Server
ADF Controller
Credential Management,
SSO Access Control
App
Config
Server
SOAP REST
Web Services
Java VM
Business
Logic
ADF Model
Encrypted
SQLite DB
JDBC
SQLite

9. Agenda
Quick Intro to Oracle MAF
Designing a Mobile-Optimized API
– On-demand loading versus data caching
Using A-Team Mobile Persistence Accelerator
– Implementing Data Caching
– Implementing Data Syncing
Copyright © 2013, Oracle and/or its affiliates. All 9 rights reserved.

10. What is a Mobile API?
API = Application Programming Interface
The API is typically hosted on a remote server (on-premise) or in the
cloud
The mobile app typically accesses the API over HTTP using SOAP or
RESTful web services
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11. What is a Mobile-Optimized API?
A mobile-optimized API uses RESTful services with JSON payload
– Easy, flexible, performant, de facto standard
– SOAP-XML creates larger payloads and is slower to process
A mobile-optimized API is designed with mobile app in mind
– Returns clean payloads that are fit for purpose
– Supports required data caching and offline use case scenarios
Existing back-end system API’s are typically NOT mobile-optimized
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1

12. Designing a Mobile-Optimized HR API
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13. Designing a Mobile-Optimized HR API
Design optimized for on-demand data loading
– Get list of departments with only id and name
– Get details of one department with summary list of employees
– Get details of one employee
Design optimized for data caching / offline usage
– Get list of departments and its employees with all attributes
Mobile-optimized API needs to be flexible to support both scenarios!
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14. Designing a Mobile-Optimized API
The mobile developer should drive API design
– knows the supported form factors and which data is needed for which
screen.
– knows the requirements for offline mode, and how mobile development tool
set supports and implements this.
– designs data caching strategies for performance optimizations
– decides which read and write actions can be performed in background
thread not impacting user-perceived performance.
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15. Implementing a Mobile-Optimized API
Use OSB to transform backend (SOAP) services to mobile API
Use mock-up API to enable parallel development
– Easy and fast with tools like MongoDB, Node.js, Express
A-Team article series “Creating a Mobile-Optimized REST API Using
Oracle Service Bus”
– http://www.ateam-oracle.com/?cat=151
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16. Agenda
Quick Intro to Oracle MAF
Designing a Mobile-Optimized API
– On-demand loading versus data caching
Using A-Team Mobile Persistence Accelerator
– Implementing Data Caching
– Implementing Data Syncing
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17. A-Team Mobile Persistence Accelerator (AMPA)
Lightweight persistence framework that works on top of MAF
Declarative consumption of REST-JSON services
Significantly speeds up implementation of data caching and data
synching
Available as open source framework hosted on GitHub
Provided “as-is”, no support, no updates from Oracle
Ideas and features from this project will be included in the MAF
product over time.
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18. AMPA – Project mobile-persistence on GitHub
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19. Runtime Persistence Architecture
MAF Model
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DepartmentService
Data Control
EntityCRUDService
extends
SQLite
DepartmentService
uses
Department
Persistence
Mapping XML
DEPARTMENTS
table
references
DBPersistence
Manager
JDBC
Statements
REST-JSON
PersistenceManager
HTTP
Requests
REST(JSON/XML)

20. AMPA - JDeveloper Wizards
Three wizard are provided to create the artefacts needed for this
runtime persistence architecture:
– Mobile Business Objects From Web Service Data Control Wizard
– Mobile Business Objects From REST Web Service Wizard
– Mobile Business Objects From Database Tables (Local persistence only)
Another wizard is provided to generate a default CRUD user interface
on top of the business layer created by one of the above wizards.
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21. Rest Wizard Demo - Toplink Data Services
M/ToplinkRest/persistence/v1.0/Model1/query/Department.findAll
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22. Demo:
Building Mobile Application – Model layer
Including data caching, offline usage and data synchronization
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Oracle 2

23. Configured InitDBLifecycleListener
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24. Create Data Control For Service Classes
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25. Creating the Mobile User Interface
Two Options
Build Using Drag and Drop
from DataControl Palette
Generate Using MAF User
Interface Generator
Wizard
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26. Building the User Interface
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27. Building the User Interface
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28. Building the User Interface
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29. Demo:
Building Mobile Application – UI layer
Including data caching, offline usage and data synchronization
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30. Using the MAF User Interface Generator
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31. Using the MAF User Interface Generator
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32. Generated User Interface Artefacts
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33. AMPA - Offline Writes and Data Syncing
If a remote persistence manager is configured, and CUD service call
fails, the service call is registered as “pending” data synch action
– Failure reason registered (device offline, service not available, etc)
On next service call, the pending synch actions are processed first in
order of creation
– When failing again, the still pending synch action is updated with date of
last synch attempt and last error message
Out-of-the-box feature: NO Java coding required
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34. Viewing Pending Data Sync Actions
A reusable “DataSync” feature is provided that can be added to your
mobile application
Register the feature in adfmf-application.xml
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35. Viewing Pending Data Sync Actions
Add a button that navigates to the data sync feature
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36. Demo:
Offline transactions and data syncing
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37. Viewing Pending Data Synch Actions
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38. Notes on Data Sync Functionality
Pending changes can become obsolete because of updates in server
data by other clients
– The server–side code should identify this and throw an error when the data
sync action sends stale data
– Stale data detection can be done by including a data revision number or
‘last-modified” timestamp in payload. This number or timestamp should
match with server-side data record
Data sync actions that keep failing need to be removed manually
– Local database might be out-of-sync, app needs to offer reconcile action
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39. Other Runtime Persistence Features
Encryption of database
Auto-cleaning of unused database segments
Lazy loading of child collections (a.k.a “Indirection”)
Entity caching to minimize object creation
Supports server-derived primary keys
FindEntityByKey
– Checks cache first, then database
Designed for customization
– Easy to override and extend default behavior
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40. AMPA - More Info
A-Team Chronicles: http://www.ateam-oracle.com/?p=29192
Includes download links to
– Source code on GitHub
– Videos
– Demo applications
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41. Summary
Start with designing and implementing a mobile-optimized REST API
Use AMPA to declaratively consume the REST/JSON web services
Use AMPA to implement data caching and syncing using the on-device
SQLite database
Think about how your end users should handle failed data sync
actions, and how to prevent updates based on stale data
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42. Copyright © 2013, Oracle and/or its affiliates. All 82 rights reserved.