JavaJ 2 EE and NET Similarities and Differences

Java/J 2 EE and. NET Similarities and Differences in the Dominant Enterprise Computing Platforms Kyle Cordes Oasis Digital Solutions Inc. Gateway Java User Group Sep. 2, 2003

Kyle Cordes z Developer / “Architect” z Consultant and Trainer z Proponent of agile, iterative, test-intensive development z Java, EJB, Oracle, SQL Server, Delphi, C++, Python, Ruby, EJB, XML, multi-tier, etc. z kylecordes. com z Oasis Digital Solutions Inc. y. Outsourced development and other services Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Disclosures - I Like all of the following: z Java z. NET z Choice of deployment platforms z Great development tools z Value for the customer / user Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Quick Poll - How many of you: z Use Java at work? z Use. NET at work? z Use a non-Java language on the JVM? z Deploy to Windows servers? z Deploy to Unix servers? Solaris? AIX? HPUX? z Deploy to Linux servers? z Use a non-Sun JVM, from IBM, HP, etc. ? Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Agenda z Overview z Technical Similarities and Differences z Non-Technical Issues z Q&A Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

What is Java? What is J 2 EE? z Platform (Infrastructure under your app) z Managed runtime environment z Marketing term for a diverse set of technology z Spec and Product (from Sun and many others) z Market z J 2 EE is the name of the “high-end” features, specs, libraries, etc. Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

What is. NET? z Platform (Infrastructure under your app) z Managed runtime environment z Marketing term for a diverse set of technology z Product (from Microsoft) z Spec (though less so) z Market (though less so) z There isn’t an overriding brand name for the enterprise features, some of them are WSE Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

What Else is. NET? z Marketing term extends beyond the platform: y. NET My Services y. Software as a Service y. Synonym for “new”, like “NT” z Most of this is going away, Microsoft is removing the. NET brand name from the next version of many products, as already happened with Windows Server 2003. Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

The Essence of. NET z Platform for building applications - like an OS z Much like Java at both macro and micro level z Microsoft’s alternative vision for what a Java-like system should look like - “the same, but different” z The Future of the Windows platform Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

. NET from a Java Perspective z Start with most of the best aspects of the Java platform (both features and texture) z Same overall idea, different names and many different design decisions z Improve on some areas, with various twists z Puts some things in platform / languages which are conventions or add-ons in Java. Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Platforms z Java tends to make platform irrelevant z. NET integrates with and boosts the value of the Windows platform (*) z (I’ll mention Mono later) Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Technical Similarities and Differences

Runtime Environment z Both provide a managed runtime environment: y. Intermediate Language / bytecode, not native code y. Garbage collection y. Security z Java JRE offers JIT and Hotspot z. NET CLR offer JIT and ngen z Common misconception among. NET partisans is that Java is interpreted Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Virtual Machine vs. Runtime z I’ve seen the idea put forth that a “runtime” is greatly different from a virtual machine. z Technically speaking, not much difference Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Languages z Java Platform: z. NET Platform: z Java language z C# z (and many others, though z Visual Basic. NET not widely used) z C++ with Managed Extensions z (and many others, more likely to see wide use) Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Major C# / Java Language Differences z Properties z Attributes z Events / Delegates z Value Type (Structs) z unsigned types z Auto-boxing z explicit interface implementation z Non-virtual methods by default (like Delphi) z Override keyword z Different method lookup rules z foreach z multi-dimensional arrays z using Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

C# Unsafe Code z Java: y. Write your unsafe code in C / C++ / etc. y. Call it with JNI - VM checks security z C#: y. Use the same language y. Mark it as unsafe y. Runtime checks security z Given that some operations require unsafe code, writing it in the same language seems like a better solution to me. Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Libraries z Java class libraries y java. io yjavax. sql z. NET BCL Base Class Library y. System. IO y. System. XML y. . . z Roughly comparable in scope Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Naming Conventions z Most of. NET naming/casing conventions are different from Java’s y. Method. Name vs method. Name y. Package. Name vs package. name z Different just to be different, in my opinion z Many more things are cased Like. This, so the casing carries slightly less information z Microsoft no longer recommends Hungarian Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

DBMS Connectivity z JDBC z JDO z SQL/J z ADO. NET z ODBC z OLE-DB, which also supports nonrelational data sources z JDBC Type 4 z. NET Managed Provider Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Deployment z Java: y. Class files / Jars z. NET: y. Assemblies z J 2 EE: Choose and install J 2 EE server, generate and compile EJB stubs, set a bunch of XML files right, create nested JARs, EARs, etc. z. NET: Copy assemblies and a few config files to a directory served by IIS Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

JARs, EXEs and DLLs z. NET Assemblies are substantially similar to JARs, but they have extra header information to make them valid Win 32 EXEs or DLLs z The header includes a stub to connect to the. NET Runtime z Result: to the end user, . NET applications have the same kinds of files as native. z Big advantage in user acceptance Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Classpath z Commonly complained about by Java detractors z. NET has a similar mechanism: load from the same directory, load from a global location (GAC), load from configured locations (much like a classpath) z. NET does not have classes as standalone files, which simplifies things. Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Versioning z. NET Assemblies carry metadata with version information z. NET Assemblies reference each other by version z Side-by-side deployment is easy, without the need to segregate Jar files z Version interop issues are similar - it’s possible to load class Foo version 1. 5 and class Foo version 2. 0, but they aren’t the same class. Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Web Presentation Toolkits z Java: z JSP/Servlets z Tab libraries z JSF z Third party toolkits (Struts etc. ) z. NET: z ASP. NET z Server-side controls y Server-side On. Click z Less emphasis on MVC z Some toolkits provide server-side On. Click just like the. NET Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Rich Client Presentation Toolkits z Java: z AWT z Swing z “Lightweight” z Layout management, the bane and the glory of Swing development z SWT and other alternatives available z. NET: z Win. Forms z “Heavyweight” = Native z Less focus on automatic layout, most layouts are pixel-based z An SWT clone is available z Win. Forms is “ 1. 0” and it shows Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

XML Support z Java: JAXP and other APIs, implementations from many vendors z. NET: Built-in (System. XML, also including interesting pull-model parsing) x. Built-in Schema, Xpath, XSLT, SOAP 1. 1 z. NET uses XML itself extensively, while Java uses lots of Properties files for older configurations; this is an artifact of the timing. Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Distributed Computing z J 2 EE: RMI, CORBA, SOAP z. NET: Remoting, SOAP, DCOM z There are third party. NET COBRA implementations. z There are third party Java DCOM bridges Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

RPCs / Distributed Objects z RMI: z JRMP or IIOP wire protocol z RMI Registry z Stubs/Skeleton z Can customize with Socket Factory z Distributed Garbage Collection! z. Net Remoting: z XML or native wire protocol, over HTTP/TCP z Activator z Can customize with Channels z Distributed Garbage Collection! Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Web Services z RPCs, Metadata, Discovery, Directories z SOAP, WSDL, UDDI, etc. z. NET: y. SOAP and WSDL in the box from Day One y. More coming in the “WSE” z Java: y. Some support in the box ymany strong solutions from 3 rd parties y. Much more in the box coming soon Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

[Web. Method] z Extensively hyped, great for demos z Not an important difference in a large app z Provided by several Java WS implementations, I was using one before. NET existed z Ludicrous to hold the fact against Java, that Java predates web services z Upcoming versions of Java and. NET will offer very similar WS support Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Clustering z J 2 EE: y. Clustering provided by App Server y. Sessions maintained by the App Server y. Platform provides the spec z Net: y. Clustering provided by OS y. Sessions maintained by IIS/OS/runtime y. Platform (Windows Server) provides the implementation Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Implementing Complex Services z Service Oriented Architectures are now the dominant paradigm y. Client app doesn’t know whether server uses domain objects z Stateless services z see Patterns of Enterprise Application Architecture, Fowler Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

The J 2 EE Approach z Stateless Session Beans for the Service Facade z Entity Beans for persistance z Many variations and recommendations out there Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

The. NET Approach z Web Services or Remoting for the Service Facade z O/R mapping is not in the box z Instead, very convenient and powerful data access components are used z Thus, Transaction Scripting favored over Domain Objects z Of course, many developers use O/R mapping and domain-object-based development. Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Message Oriented Middleware z Java: y. JMS and MDB specification z. NET: y. Easy access to Microsoft Message Queue y. COM+ Queued Components (similar to MDBs) Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Small Device Support z Java offers J 2 ME y Many third party variations also! z J 2 ME is Java with many features removed z Run on many cell phones, Palm devices, etc. z Much greater market penetration so far z. NET offers the Compact Framework z. NET CF is the. NET Framework with many features removed z Runs on Pocket PC, Smart. Phones, various embedded devices Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

In Java / J 2 EE, not in. Net z O/R Mapping, in the form of Entity Beans z Wider array of utility APIs z Public profiling and debugging APIs like JVMPI, JPDA Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

In. Net, not in Java / J 2 EE z ASP. NET Server side controls z XML Serialization z Precompilation to native code z Enumerations, Attributes, etc. Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Java /. NET Interoperability z Easy to call back and forth with Web Services y. Appropriate only for large-grained EAI interaction z Much Faster to call back and forth with CORBA z Fast but inpleasant to interoperate with COM Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Mono z “an effort to create an open source implementation of the. NET Development Framework” z Runs on Linux z Includes runtime, compiler, partial class libraries, various other infrastructure z http: //www. go-mono. com/ z Ximian, the sponsor, recently acquired by Novell z Questionable legal status given the MS patents Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Coming Soon in Java: z Generics z Auto-boxing z for() that works like foreach() z Attributes z Typesafe enums Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Coming Soon in. NET: z Generics z Object. Spaces (transparent persistance like JDO? XPath-like access to objects? ) z Async interfaces for many more opertaions Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

The Pet Shop z This Sun example web application has been used for a number of highly publicized benchmarks z None of them really mean much z Overall, you’ll get similar performance with Java and. NET Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Markets, Money, and Other Non. Technical Issues

Deployment Platforms z Java: Almost any z. NET: Any platform you want, as long as it’s Windows z To some customers, the first point is a big advantage; to others, the second is a big advantage. Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Open Source z Lots of activity on both Java and. NET z Many open Java projects have been ported to. NET. Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Jobs z Java is still apparently far ahead z St. Louis has a remarkable concentration of large Java shops z There are many MS shops here also (and quite a few MS, and now. NET-centric consulting firms). z Microsoft technology very popular is small/ medium sized firms Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Market Size Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Innovation z Microsoft can advance. NET and C# forward faster, because they have less involvement / resistance from other companies Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Money - What’s it cost to develop? z You can develop for either for little or no money y. JDK free download y. NET Framework SDK free download z Some features are not in the free downloads Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Cost Per Developer z Java can cost almost nothing per developer year; or it can cost several thousand dollars per developer year. z Microsoft offers a compelling package with MSDN Universal Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Deployment Cost z. NET deployment is “free” if you don’t count the OS z J 2 EE can be anywhere from free (Linux + JBoss) to very expensive (HPUX, AIX + Web. Logic or Web. Sphere, etc. ) z Unreasonable to compare the cost of. NET and J 2 EE per se, since the Java cost can vary tremendously by which app server you choose. Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

The Bottom Line z More alike than different z Technically, it’s unlikely that you will succeed with one and fail with the other z Java is many places where. NET is not z. NET is much better integrated with Windows, obviously the dominant platform for many customers z Java is a broad market with many producers, while. NET is very MS-centric. Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Talk Offer z This talk, or one like it with more details z In your organization z For Developers z For Managers z No Cost (in town) z No Obligation Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

XPSTL - Extreme Programming in St. Louis z Interested? Join the mailing list at xpstl. org z Worthwhile even if you are only interested in parts of XP… for example, come learn about test -intensive development. z Tomorrow night at CAIT, see web site for details. Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Questions? z Experiences? z Critiques? z Advice? Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

Links z http: //www. daimi. au. dk/~beta/ooli/Compare. ht ml Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes

THE END z Kyle Cordes kyle@kylecordes. com (636) 219 -9589 z Slides will be on my web site, http: //kylecordes. com Copyright © 2003 Oasis Digital Solutions Inc. / Kyle Cordes