軟件技術(shù)的新熱點(diǎn)面向服務(wù)的計(jì)算

1、為研究生做的講座 2005.11,1,軟件技術(shù)的 新熱點(diǎn)： 面向服務(wù)的計(jì)算 Service-Oriented Computing (SOC),西北大學(xué)軟件工程研究所 郝克剛,2,為研究生做的講座 2005.11,Service-Oriented Computing (SOC) 講座大綱,軟件技術(shù)的新熱點(diǎn)：面向服務(wù)的計(jì)算。 發(fā)展的歷史淵源：從 結(jié)構(gòu)化設(shè)計(jì)、 面向?qū)ο?、面向?gòu)件 到面向服務(wù)。 面向服務(wù)的結(jié)構(gòu) SOA 。 服務(wù)的描述。 服務(wù)的發(fā)現(xiàn)。 服務(wù)的組合。 模型和理論。 結(jié)束語(yǔ)。,3,為研究生做的講座 2005.11,一，軟件技術(shù)的新熱點(diǎn),面向服務(wù)的計(jì)算Service-Oriented Com

2、puting(SOC)， 面向服務(wù)的結(jié)構(gòu)Service-Oriented Architecture (SOA).,4,為研究生做的講座 2005.11,Bill Gates : Microsoft .NET Today June 14, 2001,Much of the information your business needs is locked up in centralized databases, served up a page at a time to individual users. Worse, Web pages are simply a “picture” of th

3、e data, not the data itself, forcing many developers back to “screen scraping” to acquire information. todays standalone applications and Web sites create islands of functionality and data. Solving such problems is the key challenge for the next generation of the Internet. At the heart of the soluti

4、on is eXtensible Markup Language, or XML. With the help of XML-based technologies such as SOAP and UDDI, they are creating a new type of software,5,為研究生做的講座 2005.11,各軟件公司紛紛提出對(duì)策。 Microsoft 比爾蓋茨關(guān)于消除信息孤島的講話。 Sun. 面向服務(wù)的體系結(jié)構(gòu)因其固有的松散耦合與互操作性，成為許多企業(yè)應(yīng)用的自然選擇。使用 J2EE 提供的 Web 服務(wù)功能可以很容易地構(gòu)建能夠訪問(wèn)現(xiàn)有業(yè)務(wù)流程的 SOA 系統(tǒng)。 IBM推

5、新軟件與服務(wù) 隸屬面向服務(wù)體系結(jié)構(gòu)。 Oracle。應(yīng)用程序網(wǎng)格計(jì)算的特征和優(yōu)點(diǎn)恰恰是面向服務(wù)體系結(jié)構(gòu)(SOA) 的特征和優(yōu)點(diǎn)。,6,為研究生做的講座 2005.11,World Wide Web Consortium (W3C),an international consortium where Member organizations, a full-time staff, and the public work together to develop Web standards 成立工作組， Web Services Addressing Working Group , Web Serv

6、ices Description Working Group Web Services Architecture Working Group Semantic Web Services Interest Group Web Services Choreography Working Group 制定標(biāo)準(zhǔn)： XML-RPC, SOAP, UDDI “yellow pages” that categorize businesses by standard taxonomies; “green pages” that document the technical information about

7、services that are exposed.,61,為研究生做的講座 2005.11,Yellow, Green, and White Pages in UDDI,62,為研究生做的講座 2005.11,WSDL UDDI Correspondence,63,為研究生做的講座 2005.11,如何從已有的Web服務(wù)經(jīng)過(guò)組合，構(gòu)造新的Web服務(wù)，已成為關(guān)注的一個(gè)焦點(diǎn)。為了得到可靠的，高質(zhì)量的服務(wù)，必須找到一種建模方法、語(yǔ)言和工具，進(jìn)行服務(wù)的組合，以及分析和驗(yàn)證。,六，服務(wù)的組合 Service Composition,64,為研究生做的講座 2005.11,Service Composi

8、tion,Industry Solution: WSDL +BPEL4WS BPEL4WS proposed by IBM and Microsoft), which specifies the roles of each of the partners and the logical flow of the message exchanges BPEL4WS provides programming-language like constructs (sequence, switch, while, pick) as well as graph-based links that repres

9、ent additional ordering constraints on the constructs.,65,為研究生做的講座 2005.11,Service Composition,WS-BPEL Business Process Execution Language for Web Services version 1.1 Contributors: IBM, BEA Systems, Microsoft, SAP AG, Siebel Systems 30 Jul 2002Updated 01 Feb 2005 Semantic Web Solution: RDF/DAML-S +

10、 Golog/Planning,66,為研究生做的講座 2005.11,Web Service Composition - Current Solutions and Open Problems,none of the approaches has developed a true planning solution to the service composition problem so far. Plans need to contain complex control structures involving loops, nondeterminism, and choice. The

11、 planning problem cannot really be expected to take place at the level of primitive actions and control structures, but seems to require to take complex plans as building blocks and synthesize multipartner interactions from them. web services create new objects at runtime, i.e., they produce message

12、 objects during their execution that then can be further processed by other services.,67,為研究生做的講座 2005.11,Standards for Web Services,68,為研究生做的講座 2005.11,W3C Candidate Recommendation 9 November 2005,Web Services Choreography Description Language Version 1.0 Choreography 辭典：安排被比作舞蹈編排的某樣?xùn)|西，如一種情況或一系列情況或

13、者是一系列計(jì)劃等： Web 服務(wù)編排描述語(yǔ)言,69,為研究生做的講座 2005.11,Web Services Choreography Description Language,WS-CDL is an XML-based language that describes peer-to-peer collaborations of participants describes collaborations of participants by defining from a global viewpoint their common and complementary observable

14、behavior, where information exchanges occur, when the jointly agreed ordering rules are satisfied,70,為研究生做的講座 2005.11,七，模型和理論。,計(jì)算機(jī)科學(xué)理論和形式化方法對(duì)軟件技術(shù)的重要作用。 計(jì)算機(jī)的誕生和圖靈機(jī)器。 高級(jí)語(yǔ)言和編譯系統(tǒng)和形式語(yǔ)言自動(dòng)機(jī)理論。 數(shù)據(jù)庫(kù)及有關(guān)關(guān)系代數(shù)理論。 高可信軟件同程序的正確性證明，形式語(yǔ)義和時(shí)態(tài)邏輯學(xué)。,71,為研究生做的講座 2005.11,Petri Net 佩特里網(wǎng),Petri 網(wǎng)是德國(guó)學(xué)者Carl Adam Petri教授于1962年在其博

15、士論文“自動(dòng)機(jī)通信”中提出的一種網(wǎng)絡(luò)圖理論。70年代以后，Petri 網(wǎng)理論引起人們的重視，得到迅速發(fā)展并應(yīng)用于解決計(jì)算機(jī)科學(xué)領(lǐng)域的問(wèn)題。 Petri 網(wǎng)既有嚴(yán)格的數(shù)學(xué)定義，又有直觀的圖形表示，特別適合描述離散事件系統(tǒng)的控制流、并發(fā)特性和異步行為。,72,為研究生做的講座 2005.11,Petri Net 是一種很好的模型,非結(jié)構(gòu)化，并行，競(jìng)爭(zhēng)，同步，,73,為研究生做的講座 2005.11,非結(jié)構(gòu)化，并行，競(jìng)爭(zhēng)，同步，,Petri Net 是一種很好的模型,74,為研究生做的講座 2005.11,非結(jié)構(gòu)化，并行，競(jìng)爭(zhēng)，同步，,Petri Net 是一種很好的模型,75,為研究生做的講座 2

16、005.11,非結(jié)構(gòu)化，并行，競(jìng)爭(zhēng)，同步，,Petri Net 是一種很好的模型,76,為研究生做的講座 2005.11,非結(jié)構(gòu)化，并行，競(jìng)爭(zhēng)，同步，,Petri Net 是一種很好的模型,77,為研究生做的講座 2005.11,非結(jié)構(gòu)化，并行，競(jìng)爭(zhēng)，同步，,Petri Net 是一種很好的模型,78,為研究生做的講座 2005.11,非結(jié)構(gòu)化，并行，競(jìng)爭(zhēng)，同步，,Petri Net 是一種很好的模型,79,為研究生做的講座 2005.11,軟件工程研究所在Petri 網(wǎng)方面的工作,郝克剛: “Petri 網(wǎng)與結(jié)構(gòu)的 Petri 網(wǎng)”，微電子學(xué)與計(jì)算機(jī)，1985年 第6期。 郝克剛，段振華：“

17、多出口 Petri 網(wǎng)與 Petri 網(wǎng)的等價(jià)性”， 計(jì)算機(jī)學(xué)報(bào)， 郝克剛，張 慧，侯 紅：“Petri 網(wǎng)工具(GPNT)的設(shè)計(jì)與實(shí)現(xiàn)”， 軟件學(xué)報(bào)， 1991年 第3期。 郝克剛,葛瑋：“關(guān)于高級(jí)網(wǎng)系統(tǒng)的等價(jià)及譜系的研究”，計(jì)算機(jī)學(xué)報(bào)，1993 年第7期， 郝克剛：開(kāi)放網(wǎng)-交互式并行系統(tǒng)的模型，西北大學(xué)學(xué)報(bào)（自然科學(xué)版），1997, 5。,80,為研究生做的講座 2005.11,軟件工程研究所在Petri 網(wǎng)方面的工作,岳曉麗,楊 斌,郝克剛.信牌驅(qū)動(dòng)式工作流計(jì)算模型. 計(jì)算機(jī)研究與發(fā)展, 2000,(37) 12 郝克剛，王斌君。.非確定Petri網(wǎng)。小型微型計(jì)算機(jī)系統(tǒng)（2003。3（2

18、4）。 郝克剛，王斌君。 擴(kuò)展的信牌驅(qū)動(dòng)模型與Petri網(wǎng)。 計(jì)算機(jī)應(yīng)用與軟件（2004.2(21) ）。 郝克剛，王斌君，安 貴。 WPDL中的JOIN語(yǔ)義問(wèn)題和分區(qū)解決方案。計(jì)算機(jī)科學(xué)（2003。7（30）。 Kegang Hao：Two Formal Models of Interactive Machine ,Proceedings of The Third Asian Workshop on Foundations of Software, Xian, China, November, 2004；,81,為研究生做的講座 2005.11,羅賓. 米爾納 的演算,The -calcul

19、us是 Robin Milner在下述演算系統(tǒng)的基礎(chǔ)上建立的。 Churchs -calculus equivalent to Turing Machines his earlier CCS (calculus for communicating systems) Anthony Hoare process algebra CSP (communicating sequential processes).,82,為研究生做的講座 2005.11,The Monadic -calculus Basic ideas,The most primitive entity in -calculus is

20、 a name. Names, infinitely many, are x,y, X there is only one other kind of entity: a process. Processes are P,Q, P and are built from names by this syntax P := iIi Pi | P | Q | !P | (x)P,83,為研究生做的講座 2005.11,P := iIi Pi | P | Q | !P | (x)P,Here I is a finite indexing set. in the case I = we write th

21、e sum as 0. In a summand P the prefix represents an atomic action, the first action performed by P . There are two basic forms of prefix : x(y), which binds y in the prefixed process, means “input some name ( call it y ) along the link named x” , which does not bind y, means “output the name y along

22、 the link named x ”,84,為研究生做的講座 2005.11,P := iIi Pi | P | Q | !P | (x)P,The summation form iIi Pi represents a process able to take part in one, but only one, of several alternatives for communication. Processes in this form are called normal processes (because as we see later, all processes can be

23、converted to this normal form) For normal processes M,N, N we shall use the following syntax: N := P | 0 | M + N,85,為研究生做的講座 2005.11,P := iIi Pi | P | Q | !P | (x)P,P |Q simply means that P and Q are concurrently active so they can act independently but can also communicate !P means P |P | as many c

24、opies as you wish There is no risk of infinite concurrent activity, our reduction rules will see to that. The operator “!” is called replication. A common instance of replication is !P ,a resource which can only be replicated when a requester communicates via ,86,為研究生做的講座 2005.11,P := iIi Pi | P | Q

25、 | !P | (x)P,Finally, (x)P, new x in P restricts the use of the name x to P. Another way of describing it is that it declares a new unique name x distinct from all external names for use in P,87,為研究生做的講座 2005.11,Some simple examples,reduction,88,為研究生做的講座 2005.11,SOC 涉及的研究方向 （上）,Service Description S

26、ervice Discovery Service Composition Service Monitoring Service Deployment Service Middleware Service Oriented Architectures Service Development and Maintenance Programming models for Service Oriented Applications,89,為研究生做的講座 2005.11,SOC 涉及的研究方向 （中）,Methodologies for Service Oriented Applications Novel business models for service-oriented applications Economical implications of Web services and SOAs Formal Methods for Service Oriented Architectures Service Testing and Validation Service Lifecycle Managemen