Migrating traditional Java EE applications to mobile Serge Pagop Sr. Channel MW Solution Architect, Red Hat spagop@redhat.com Burr Sutter Product Management Director, Red Hat bsutter@redhat.com 2014-04-16
Agenda Migration motivations Traditional Java (2) EE technologies usage Migration approaches Migration of layers Modernize to Java EE 6 technologies Plan for mobile REST fits well with the mobile strategy Which Mobile application model to choose? Mobile Gateway architecture Mobile + JBoss EAP Runtime Demo and Q&A 2
Motivations Innovation, integration, cost reduction, modernization Market Demand, Time to market, Go-To Market strategy Complexity, performance, stability, security Vendor lock-in, lack of functionalities, standards compliance Multi-tenancy, Ready for the Cloud Penetrate New Market Segment Increase developer productivity 3
Motivations MOBILE VS. DESKTOP - Projection Source: visual.ly 4
Traditional Java (2) EE technologies usage Current situation 5
Traditional Java (2) EE technologies usage Current situation Persistence layer Standards are JDBC, CMP, BMP, JPA, JDO Non-Standards are Hibernate, ibatis,... Business layer Standards are Enterprise JavaBeans 2.x / 3.0 Non-Standards are Spring Framework, JBoss Seam, Google Guice,... Communication layer Standards are JAX-WS, JAX-RPC, RMI Non-Standards are legacy Web Service Frameworks 6
Traditional Java (2) EE technologies usage Cont. Current situation Presentation layer Standards are JSP+Servlets, JSF 1.2/2.0 Non-Standards are: Struts, Tapestry, GWT, Wicket,... 7
Migration approaches Complete migration Layer-oriented migration Module-oriented migration First Action Item: Migration Assessment 8
Migration assessment Looks at all facets of applications and infrastructure Helps to understand the risks, savings, and anticipated costs Enables stakeholders to scope the engineering time and effort required to migrate applications Free open source tool for Java EE migration assessment Analyzes code and generates report with known issues Provides an estimate of effort required to make changes Offers suggestions for replacement code Highlights vendor specific implementations 10,000 Foot View Report http://www.jboss.org/migration 9
Complete migration Big Bang style Unique new development Migration of the entire application in a new system High Complexity because of new development 10
Layer-oriented migration Based on layer oriented approach: each layer needs a specific handling Complexity is defined through Multiple migration with associated test and acceptance processes Migration of a layer affects overlying layers 11
Module-oriented migration Defined as Migration On Demand Migration of technical modules will be taken in consideration Complexity is defined through A mix of technologies of new and old ones Delimitation of technical modules 12
Persistence layer migration Current-Situation SQL/JDBC Data Access SQL Queries DAO / Repository Pattern Providing Value Objects Future-Situation JPA 2.0 Challenges Domain model introduction with relationship Detached entity objects handling Adaption of entity objects with unique identity EJB 2.x Data Access JPA 2.0 Challenges CMP 2.x - Entity classes and XML descriptors BMP 2.x - CRUD callback methods Domain model introduction with relationship Detached entity objects handling Adaption of entity objects with unique identity Data Access Objects introduction Hibernate Data Access JPA 2.0 Challenges O/R Mapping via XML Using Hibernate APIs No challenges (Hibernate is JPA provider in JBoss EAP) May be some challenges with proprietary Hibernate features JDO Data Access JPA 2.0 Challenges Domain model approach similar to JPA (based on annotation or configuration) JDO and JPA have similarities 13
Business layer migration Current-Situation EJB 2.x components Stateless and Stateful Session Beans EJB 2.x Pattern and communication Future-Situation EJB 3.1 Challenges No challenges Eliminate J2EE Pattern Eliminate proprietary infrastructure code EJB 2.x components CDI 1.0 Challenges Stateless and Stateful Session Beans EJB 2.x Pattern and communication No challenges Eliminate J2EE Pattern Eliminate proprietary infrastructure code Spring lightweight DI Framework CDI 1.0 Challenges Based on XML or annotation Strong integration support (JDBC template, Tx template, JMS template, Mail template) Supports other annotations (@Resource, @Inject) No challenges May be some challenges with Spring Add-On Different semantics in the field of scopes 14
Communication layer migration Future-Situation Introduction of a new communication interface JAX-RS - Challenges New fresh start Provide distinct URI for each resource you wish to expose Expose REST services by injecting EJBs into JAX-RS annotated POJOs Use nouns in the URIs Use links in your responses Make service stateless Define what actions should be able to perform on each resource Map the actions to an appropriate HTTP verbs (@DELETE, @GET, @POST, @PUT, @HEAD) Use JSON via JAXB as interchange data format 15
Presentation layer migration Standard like JSP with Servlet or JSF 2.0/2.1 and non-standard web frameworks like Struts, Tapestry, GWT, do not have a migration path in a mobile strategy Mobile-First strategy creating pages, UI components that address the constraints of mobile, then progressively enhances the experience to other screen spaces, features, and more Client side needs a clean / fresh start 16
Modernize to Java EE 6 technologies Future situation to enable mobile capabilities 17
REST fits well with mobile strategy REST is flexible and adequate for Client-Server communication Communication happens over HTTP using REST styles JSON over HTTP/HTTPs should be used for data-interchange Stateless, Cacheable, Lightweight, Scalable Using HTTP verbs (DELETE, GET, POST, PUT) Using Web technologies and security standards Fully supported in JBoss EAP (Java EE 6 compliant environment) by a JAX-RS implementation (RESTEasy) 18
REST fits well with mobile strategy Securing endpoints - Possibilities JBoss EAP 6.2 Basic Auth RealmUsersRoles with *-users.properties and *-roles.properties files Database login module - users and roles from a database system LDAP login module users and roles from a LDAP server JBoss EAP 6.3 PicketLink Identity Management (IDM) 19
Which Mobile application model to choose? Mobile Web HTML5 <html> <body> <div id= name /> <script src= x.js /> </body> </html> Native Shell HTML5 <html> <body> <div id= name /> <script src= x.js /> </body> </html> Native App Native Code Apple apple apple Android android Windows windows IOS ios ios Jave Objectve c Device Browser Apache Cordova Objective-C / Android Java Pros: Instant Deployment Reuse of Web Talents No App Stores Pros: Cross-Platform Native Device Features Push App Stores Pros: Limitless capability Cons: Limited Device Features Limited Offline Capabilities No Push No App Stores Cons: HTML/JS-based UI Non-native look & feel App Stores 20 Cons: Unique Codebases Unique skill-sets Addressing multiple screen dimensions App Stores
Mobile Gateway architecture Mobile + JBoss EAP Server Runtime JBoss Enterprise Application Platform Internal Internal System System AA APNS Internet GCM LDAP LDAP DB DB JAX-RS JAX-RS Fuse Fuse or or FSW FSW REST Unified Push Server push notification Internal Internal System System BB MSSQL MSSQL SalesForce SalesForce DB/2 DB/2 SAP SAP DB DB Firewall 21 Oracle Oracle
Demo Time! 22
Questions? Serge Pagop Email: spagop@redhat.com Burr Sutter Email: bsutter@redhat.com