Friday meeting memo
1. with/without XML syntax
Is it a language with everything in XML or just to manipulate only XML data? For example, in CDL/BPEL/XLANG/WSFL, everything is XML, including data and the language itself. While in XQuery and XL languages (http://xl.in.tum.de/), the language syntax is independent of XML.2. Composition/specification of Web Services
Is it a language to compose or specify Web Services? The former one is programming in large and the latter programming in small. In BPEL, there is a trend to provide both functionalities by introducing Java or C# code snippet.
The Madhu paper proposes a factory service to build distributed applications. A distributed application consists of many XCAT components. A running instance of an XCAT component is a web service with uses-port and provides-port. This paper defines an XML language to describe the connections between components. Compared with WSFL/BPEL, this CCA based approach gets rid of the central flow engine. So, there is no need of extra effort to describe information exchange between components. This approach can be used complementarily with BPEL. The description of connections between components can work as an annotation to service partners in BPEL. Doing so will get benefit from both of them.3. Imperative/declarative programming
Imperative programming gives a list of instructions to execute in a particular order. Declarative programming describes a set of conditions and lets the computer figure out how to satisfy them. That is, imperative programming specifies “how” whereas declarative programming describes what is going to be done without specifying “how”. The annotation mechanism is a way to use declarative and imperative programming together. Annotation is used to associate declarative information (metadata) with imperative program elements such as classes, methods, fields, parameters, local variables and packages. Annotation is supported in JDK 1.5 and .NET Framework.
() How to deal with OOP stuff?
A C++ object can definitely be converted to XML. The problem is how to write the correspondent C code.
1. C is not an OOP programming language
If we use XML to describe an OOP program, we need some tags to represent Class. Then how can C understand such tags related to OOP stuff?
2. C has a Pointer type which is address-space-relative
How could XML to specify a Pointer?
Is it a language with everything in XML or just to manipulate only XML data? For example, in CDL/BPEL/XLANG/WSFL, everything is XML, including data and the language itself. While in XQuery and XL languages (http://xl.in.tum.de/), the language syntax is independent of XML.2. Composition/specification of Web Services
Is it a language to compose or specify Web Services? The former one is programming in large and the latter programming in small. In BPEL, there is a trend to provide both functionalities by introducing Java or C# code snippet.
The Madhu paper proposes a factory service to build distributed applications. A distributed application consists of many XCAT components. A running instance of an XCAT component is a web service with uses-port and provides-port. This paper defines an XML language to describe the connections between components. Compared with WSFL/BPEL, this CCA based approach gets rid of the central flow engine. So, there is no need of extra effort to describe information exchange between components. This approach can be used complementarily with BPEL. The description of connections between components can work as an annotation to service partners in BPEL. Doing so will get benefit from both of them.3. Imperative/declarative programming
Imperative programming gives a list of instructions to execute in a particular order. Declarative programming describes a set of conditions and lets the computer figure out how to satisfy them. That is, imperative programming specifies “how” whereas declarative programming describes what is going to be done without specifying “how”. The annotation mechanism is a way to use declarative and imperative programming together. Annotation is used to associate declarative information (metadata) with imperative program elements such as classes, methods, fields, parameters, local variables and packages. Annotation is supported in JDK 1.5 and .NET Framework.
() How to deal with OOP stuff?
A C++ object can definitely be converted to XML. The problem is how to write the correspondent C code.
1. C is not an OOP programming language
If we use XML to describe an OOP program, we need some tags to represent Class. Then how can C understand such tags related to OOP stuff?
2. C has a Pointer type which is address-space-relative
How could XML to specify a Pointer?
