Dirk Burkholz My project Overview & Motivation Core principles - PowerPoint PPT Presentation

Dirk Burkholz

 My project  Overview & Motivation  Core principles and techniques  Spotlight on one technique  Further features  Conclusion Dirk Burkholz - The Spring Framework 14.01.2009 for Java and .NET 2

 GLOBUS group, hypermarkets  Spring for Java in use for several J2EE projects  Launch of software-aided business process management based on .NET  Project: Evaluation if the knowledge and experience about Spring for Java can easily be transferred to projects in C#.NET using Spring.NET  Sample project using some core features of Spring Dirk Burkholz - The Spring Framework 14.01.2009 for Java and .NET 3

 Core Principles  Inversion of Control (IoC)  Dependency Injection (DI)  Aspect Oriented Programming (AOP)  Further features  Template-based database access (DAO support)  Webservices  … Dirk Burkholz - The Spring Framework 14.01.2009 for Java and .NET 4

 Rod Johnson, J2EE consultant, found some drawbacks in J2EE design  He collected best practices to avoid this drawbacks in his book „Expert One -on-one J2EE Design and Development“ in 2002; a very basic framework was already included  Now: Spring Framework for Java 2.5 in 2007  Mark Pollack‘s first .NET port in 2003  Now: Spring.NET 1.2 in 2008 Dirk Burkholz - The Spring Framework 14.01.2009 for Java and .NET 5

 Responsibility to instatiate new objects not by the using object but by the IoC container  Coding against interfaces and superclasses, not implementations  Uses Dependency Injection  XML-based context describing managed objects, their properties and dependencies to other managed objects Dirk Burkholz - The Spring Framework 14.01.2009 for Java and .NET 6

<bean id =„student1“ class =„Student“> <property name =„ studentid “ value =„42“ /> … </bean> … <bean id =„university0“ class =„University“> <property name =„ bestStudent “ ref =„student1“ /> … </bean> Dirk Burkholz - The Spring Framework 14.01.2009 for Java and .NET 7

 Injecting dependencies of managed objects by the IoC container instead of instatiating dependent objects by new ObjectType()  Spring uses  Setter Injection: matching properties by name  String property xy – setXy(String s)  Constructor Injection: matching constructur arguments by order and type  Object obj, int argument i – new obj(i) Dirk Burkholz - The Spring Framework 14.01.2009 for Java and .NET 8

 Crosscutting concerns are requirements orthogonal to the software design/ decomposition, e.g. logging  Joinpoints are points in the program flow, Pointcuts select a subset of them  Advices add the desired functionality at the joinpoints selected by pointcuts  Spring supports Before-, Around-, After-, AfterException and AfterReturning Advices Dirk Burkholz - The Spring Framework 14.01.2009 for Java and .NET 9

 Drawbacks to classic AOP (e.g. AspectJ)  Advising managed objects only  Advising public methods only  No advices for advised methods  Advices are singletons  Access to method invocation: arguments, return value, thrown exception  Possibility to check, change or omit return values Dirk Burkholz - The Spring Framework 14.01.2009 for Java and .NET 10

SPRING JAVA SPRING.NET  AspectJ-like  J2SE dynamic proxies to  Full advising of advice interfaces interfaces only  CGlib2 proxies to  Advising virtual advice classes methods of classes only  Annotation-based syntax possible Dirk Burkholz - The Spring Framework 14.01.2009 for Java and .NET 11

 Central concept: Template  Capsules and manages connection to data source  Provides methods mapping result sets to more generic collections/types  Provides many helper methods  Translates vendor- specific exceptions to Spring‘s generic DataAccessException hierarchy (using SQLExceptionTranslator) Dirk Burkholz - The Spring Framework 14.01.2009 for Java and .NET 12

SPRING JAVA SPRING.NET  DataSource  DbProvider  JdbcTemplate  AdoTemplate  Mapping to Map/List  Mapping to DataSet queryForMap()/List DataSetCreateWithParams()  Statement parameters  Statement parameters by object array by IDbParameters  queryForObject() and  ExecuteScalar() only specialized methods Dirk Burkholz - The Spring Framework 14.01.2009 for Java and .NET 13

 Goal: Webservice support easier than with J2EE/ASP.NET  Using webservice proxies  Testing scenario:  Cut between DataProvider and Factory  Connections via webservice  Java – Java  .NET – .NET  Java - .NET  .NET – Java Dirk Burkholz - The Spring Framework 14.01.2009 for Java and .NET 14

 Core principles are the same except for Java/.NET core technology differences  Spring for Java developers can easily apply their knowledge when developing Spring.NET applications  Some differences in details, especially naming  Developers can easily overcome this by using code completion and looking up the reference’s section Spring.NET for Java developers  Spring for Java has more features than Spring.NET  Core features are already well supported, so certain features are only missing for special cases  More features: Web MVC, Security, Validation, … Dirk Burkholz - The Spring Framework 14.01.2009 for Java and .NET 15

 The Spring Framework - Reference Documentation: http://static.springframework.org/spring/docs/2 .5.x/reference/index.html  The Spring.NET Framework – Reference Documentation: http://www.springframework.net/docs/1.2.0/ref erence/html/index.html  Rod Johnson. Expert One-on-one J2EE Design and Development (Programmer to Programmer). Wiley & Sons 2003. ISBN: 978-0764543852 Dirk Burkholz - The Spring Framework 14.01.2009 for Java and .NET 16