亚洲欧美激情另类校园_欧美理论电影在线播放_国产精品久久久一区_久久99国产精品久久久久久久久_亚洲人成网站999久久久综合_日韩av日韩在线观看_欧美精品激情在线_…久久精品99久久香蕉国产_亚洲最大福利网站_久久精品欧美视频_国产精品免费视频久久久_欧美一区二区三区图_国产精品一区二区久久精品_中国日韩欧美久久久久久久久_亚洲免费福利视频_最新69国产成人精品视频免费


曙海教育集團論壇開發語言培訓專區Microsoft.NET Framework → Microsoft .NET vs. J2EE:


  共有10987人關注過本帖樹形打印

主題:Microsoft .NET vs. J2EE:

美女呀,離線,留言給我吧!
wangxinxin
  1樓 個性首頁 | 博客 | 信息 | 搜索 | 郵箱 | 主頁 | UC


加好友 發短信
等級:青蜂俠 帖子:1393 積分:14038 威望:0 精華:0 注冊:2010-11-12 11:08:23
Microsoft .NET vs. J2EE:  發帖心情 Post By:2010-12-15 11:13:20

What exactly is the .NET platform [and] how does the .NET architecture measure up against J2EE?

Java runs on any platform with a Java VM. C# only runs in Windows for the foreseeable future.

.NET and J2EE offer pretty much the same laundry list of features, albeit in different ways.

By allowing cross-language component interactions, .NET is enfranchising Perl, Eiffel, Cobol, and other programmers.

.NET is a good thing for those of you committed to Microsoft architectures.

.NET will undoubtedly become the default development environment for Microsoft platforms.

However, several of the goals of the .NET platform are fairly lofty and not at all guaranteed to fly, at least not in the short term.

It would be easy to dismiss .NET as more Microsoft marketing-ware and continue on your merry way. But don't.

[Microsoft is] fighting Java and open source initiatives on their own terms, putting their own spin on "open" and attempting to directly address the needs of developers.

If you consider yourself an evangelist for Java or open source platforms, then the nature of the war is changing. Be prepared.

Microsoft has put a stake in the ground with SOAP, and they're pushing hard to put something understandable and useful in the hands of developers. J2EE proponents need to do the same with their platform.

Even if you don't write code dedicated to Microsoft platforms, you have probably heard by now about Microsoft .NET, Microsoft's latest volley in their campaign against all things non-Windows. If you've read the media spin from Microsoft, or browsed through the scant technical material available on the MSDN site, or even if you attended the Microsoft Professional Developers' Conference (where the .NET platform was officially "launched"), you're probably still left with at least two big questions:

  • What exactly is the .NET platform?
  • How does the .NET architecture measure up against J2EE?

And, if you think more long-term, you might have a third question rattling around your head:

  • What can we learn from the .NET architecture about pushing the envelope of enterprise software development?

The .NET framework is at a very early stage in its lifecycle, and deep details are still being eked out by the Microsoft .NET team. But we can, nevertheless, get fairly decent answers to these questions from the information that's already out there.

What is it?

Current ruminations about .NET in various forums are reminiscent of the fable of the three blind men attempting to identify an elephant: It's perceived as very different things, depending on your perspective. Some see .NET as Microsoft's next-generation Visual Studio development environment. Some see it as yet another new programming language (C#). Some see it as a new data-exchange and messaging framework, based on XML and SOAP. In reality, .NET wants to be all of these things, and a bit more.

First, let's get some concrete details. Here's one cut at an itemized list of the technical components making up the .NET platform:

  • C#, a "new" language for writing classes and components, that integrates elements of C, C++, and Java, and adds additional features, like metadata tags, related to component development.

  • A "common language runtime", which runs bytecodes in an Internal Language (IL) format. Code and objects written in one language can, ostensibly, be compiled into the IL runtime, once an IL compiler is developed for the language.

  • A set of base components, accessible from the common language runtime, that provide various functions (networking, containers, etc.).

  • ASP+, a new version of ASP that supports compilation of ASPs into the common language runtime (and therefore writing ASP scripts using any language with an IL binding).

  • Win Forms and Web Forms, new UI component frameworks accessible from Visual Studio.

  • ADO+, a new generation of ADO data access components that use XML and SOAP for data interchange.

How do .NET and J2EE compare?

As you can see, the .NET platform has an array of technologies under its umbrella. Microsoft is ostensibly presenting these as alternatives to other existing platforms, like J2EE and CORBA, in order to attract developers to the Windows platform. But how do the comparisons play out item-by-item? One way to lay out the alternatives between .NET and J2EE is shown in the following table:

Microsoft.NET J2EE Key differentiators
C# programming language Java programming language C# and Java both derive from C and C++. Most significant features (e.g., garbage collection, hierarchical namespaces) are present in both. C# borrows some of the component concepts from JavaBeans (properties/attributes, events, etc.), adds some of its own (like metadata tags), but incorporates these features into the syntax differently.

Java runs on any platform with a Java VM. C# only runs in Windows for the foreseeable future.

C# is implicitly tied into the IL common language runtime (see below), and is run as just-in-time (JIT) compiled bytecodes or compiled entirely into native code. Java code runs as Java Virtual Machine (VT) bytecodes that are either interpreted in the VM or JIT compiled, or can be compiled entirely into native code.

.NET common components (aka the ".NET Framework SDK") Java core API High-level .NET components will include support for distributed access using XML and SOAP (see ADO+ below).
Active Server Pages+ (ASP+) Java ServerPages (JSP) ASP+ will use Visual Basic, C#, and possibly other languages for code snippets. All get compiled into native code through the common language runtime (as opposed to being interpreted each time, like ASPs). JSPs use Java code (snippets, or JavaBean references), compiled into Java bytecodes (either on-demand or batch-compiled, depending on the JSP implementation).
IL Common Language Runtime Java Virtual Machine and CORBA IDL and ORB .NET common language runtime allows code in multiple languages to use a shared set of components, on Windows. Underlies nearly all of .NET framework (common components, ASP+, etc.).

Java's Virtual Machine spec allows Java bytecodes to run on any platform with a compliant JVM.

CORBA allows code in multiple languages to use a shared set of objects, on any platform with an ORB available. Not nearly as tightly integrated into J2EE framework.

Win Forms and Web Forms Java Swing Similar web components (e.g., based on JSP) not available in Java standard platform, some proprietary components available through Java IDEs, etc.

Win Forms and Web Forms RAD development supported through the MS Visual Studio IDE - no other IDE support announced at this writing. Swing support available in many Java IDEs and tools.

ADO+ and SOAP-based Web Services JDBC, EJB, JMS and Java XML Libraries (XML4J, JAXP) ADO+ is built on the premise of XML data interchange (between remote data objects and layers of multi-tier apps) on top of HTTP (AKA, SOAP). .NET's web services in general assume SOAP messaging models. EJB, JDBC, etc. leave the data interchange protocol at the developer's discretion, and operate on top of either HTTP, RMI/JRMP or IIOP.

The comparisons in this table only scratch the surface. Here's an executive summary of .NET vs. J2EE:

Features: .NET and J2EE offer pretty much the same laundry of list of features, albeit in different ways.

Portability: The .NET core works on Windows only but theoretically supports development in many languages (once sub-/supersets of these languages have been defined and IL compilers have been created for them). Also, Net's SOAP capabilities will allow components on other platforms to exchange data messages with .NET components. While a few of the elements in .NET, such as SOAP and its discovery and lookup protocols, are provided as public specifications, the core components of the framework (IL runtime environment, ASP+ internals, Win Forms and Web Forms component "contracts", etc.) are kept by Microsoft, and Microsoft will be the only provider of complete .NET development and runtime environments. There has already been some pressure by the development community for Microsoft to open up these specifications, but this would be counter to Microsoft's standard practices.

J2EE, on the other hand, works on any platform with a compliant Java VM and a compliant set of required platform services (EJB container, JMS service, etc., etc.). All of the specifications that define the J2EE platform are published and reviewed publicly, and numerous vendors offer compliant products and development environments. But J2EE is a single-language platform. Calls from/to objects in other languages are possible through CORBA, but CORBA support is not a ubiquitous part of the platform.

The Bigger Picture

These last points highlight some of the key differentiators between .NET and J2EE, and point towards Microsoft's real play here. Microsoft is doing two very notable things with .NET: It is opening up a channel to developers in other programming languages, and it is opening up a channel to non-.NET components by integrating XML and SOAP into their messaging scheme.

By allowing cross-language component interactions, .NET is enfranchising Perl, Eiffel, Cobol, and other programmers by allowing them to play in the Microsoft sandbox. Devotees of these languages are particularly amenable to gestures like this, since for the most part they have felt somewhat disenfranchised and marginalized in the Microsoft/Sun/Open Source wars. And by using XML and SOAP in their component messaging layer, Microsoft is bolstering their diplomatic face and adding an element of openness to their platform, providing ammunition against claims of proprietary behavior.

What's the correct response?

For Microsoft developers:

.NET is a good thing for those of you committed to Microsoft architectures. ASP+ is better than ASP, ADO+ is better, but different, than ADO and DCOM, C# is better than C and C++. The initial version of .NET won't be real until sometime in 2001, so you have some time to prepare, but this will undoubtedly become the default development environment for Microsoft platforms. And if you're developing within the Microsoft development framework now, you will undoubtedly benefit from adopting elements of the .NET framework into your architectures.

However, several of the goals of the .NET platform are fairly lofty and not at all guaranteed to fly, at least not in the short term. The IL common language runtime, for example, has some fairly significant hurdles to overcome before it has any real payoff for developers. Each language that wants to integrate with the component runtime has to define a subset/superset of the language that maps cleanly into and out of the IL runtime, and has to define constructs that provide the component metadata that IL requires. Then compilers (x-to-IL and IL-to-x) will have to be developed to both compile language structures (objects, components, etc.) into IL component bytecodes, and also generate language-specific interfaces to


支持(0中立(0反對(0單帖管理 | 引用 | 回復 回到頂部

返回版面帖子列表

Microsoft .NET vs. J2EE:








簽名
亚洲欧美激情另类校园_欧美理论电影在线播放_国产精品久久久一区_久久99国产精品久久久久久久久_亚洲人成网站999久久久综合_日韩av日韩在线观看_欧美精品激情在线_…久久精品99久久香蕉国产_亚洲最大福利网站_久久精品欧美视频_国产精品免费视频久久久_欧美一区二区三区图_国产精品一区二区久久精品_中国日韩欧美久久久久久久久_亚洲免费福利视频_最新69国产成人精品视频免费
国产私拍福利精品视频二区| 日韩av电影免费在线| 欧美暴力喷水在线| 99在线|亚洲一区二区| 国产精品网红福利| 影音先锋男人资源在线| 久久偷看各类wc女厕嘘嘘偷窃| 欧美午夜www高清视频| 99精品国自产在线| 91在线免费看片| 国产午夜亚洲精品一级在线| 国产精品无码久久久久| 色噜噜国产精品视频一区二区| 欧美变态tickling挠脚心| 中文在线资源| 欧美大片网址| 欧美性大战久久久久| 国产精品igao视频网网址不卡日韩| 成人国产精品一级毛片视频| 最近2019年好看中文字幕视频| 欧美亚洲国产精品| 国产高清在线观看| 国产精品美女久久久久人| 香蕉视频国产在线观看| 精品久久久久久久久中文字幕| 成人另类视频| 在线性视频日韩欧美| 乱色588欧美| 九色91视频| 青娱乐精品视频在线| 黑人巨大精品欧美一区二区免费| 欧美aaa大片视频一二区| 亚洲专区中文字幕| 国模雨婷捆绑高清在线| 国产欧美日韩久久| 天堂av一区二区三区在线播放| 亚洲影院天堂中文av色| 久久人人九九| 久久影视电视剧免费网站清宫辞电视| 国产日韩欧美日韩| 久久综合成人| 国产精品高潮呻吟久久av黑人| 91精品视频一区| 国产精品美女网站| 欧美日韩高清在线播放| 久久综合五月天| 亚洲第一精品久久忘忧草社区| 欧美激情在线播放| 97se狠狠狠综合亚洲狠狠| 99v久久综合狠狠综合久久| 久久久精品日韩欧美| 国产伦精品一区二区三区在线| 成人高清视频在线| 欧美18一19xxx性| 擼擼色在线看观看免费| 成人全视频免费观看在线看| 欧美jizzhd欧美| aiss精品大尺度系列| 香蕉视频国产在线观看| 亚洲欧美一区二区久久| 国产精品jizz在线观看美国| 色一情一乱一乱一91av| 91美女福利视频| 国产成人97精品免费看片| 91国产丝袜在线放| 久久久久国产精品| 亚洲视频在线免费看| 日本一区二区三区视频免费看| 亚洲成人短视频| 爱情岛亚洲播放路线| 精品一区二区三区久久| 自由的xxxx在线视频| 波多一区二区| 欧美性猛交xxxx乱大交退制版| 68国产成人综合久久精品| 国产一区二区三区色淫影院| 亚洲国产成人av好男人在线观看| 海角社区69精品视频| 黄色免费在线网站| www在线播放| 欧美日韩国产精品成人| 亚洲黄色成人久久久| 亚洲一级毛片| 全球中文成人在线| 影音先锋日韩资源| 精品国产免费久久久久久尖叫| 日韩黄色免费电影| 福利视频网站一区二区三区| 精品一区二区三区久久久| 亚洲ai欧洲av| 成人动漫视频在线观看完整版| 久久人人爽人人爽人人片av不| 电影一区二区三区久久免费观看| 久久福利视频一区二区| 亚洲视频免费观看| 麻豆视频成人| 国产精品久久天天影视| 一区二区三区在线观看国产| 日韩av电影免费观看高清完整版| 亚洲成人资源网| 久久久女女女女999久久| 亚洲午夜av电影| 波多野洁衣一区| 免费欧美视频| xxav国产精品美女主播| 天天躁日日躁狠狠躁欧美巨大小说| 成人精品高清在线视频| 欧美亚洲一区二区在线观看| 666欧美在线视频| 九九九九久久久久| 亚洲欧洲日韩av| 国精产品一区二区三区有限公司| 亚洲动漫第一页| 午夜小视频在线| 日本综合视频| 国产精品久久久久99| 免费久久久一本精品久久区| www.久久草| 黄色成人小视频| 亚洲影视中文字幕| 亚洲自拍偷拍色片视频| 欧美日韩在线视频免费观看| 国产精品6699| 一道在线中文一区二区三区| 欧美一区自拍| 精品国产91乱高清在线观看| 一区二区三区四区高清精品免费观看| 色综合久久久久综合一本到桃花网| 激情婷婷亚洲| 欧美哺乳videos| 日本网站在线免费观看视频| 亚洲日本一区二区| 欧美激情护士| 自拍偷拍欧美专区| 麻豆精品少妇| 91精品国产高清久久久久久91裸体| а_天堂中文在线| 午夜精品视频在线| 蜜桃久久精品一区二区| 亚洲视频大全| 中文字幕一区二区三区四区久久| 91蜜桃传媒精品久久久一区二区| 欧美—级a级欧美特级ar全黄| 亚洲精品国产成人影院| 日本福利专区在线观看| 日韩精品不卡一区二区| 美女www一区二区| 香蕉成人久久| 国内精品久久久久久99蜜桃| av成人观看| 91色乱码一区二区三区| 欧美久久在线| 精品sm捆绑视频| 丁香影院在线| 综合亚洲深深色噜噜狠狠网站| 极品中文字幕一区| 亚洲黄色免费| 成人黄色av网站在线| 范冰冰一级做a爰片久久毛片| 色婷婷综合久久久中字幕精品久久| 成人短视频在线观看| 亚洲一区二区三区乱码aⅴ| 国产精品黄视频| 蜜桃视频网站在线|