Hi Andrew, Note that I am using angular. soap. js and not able to call web services. wsdl get retrieves ok, but next call is OPTIONS and that call crashes as bad. Part 1 Developing my first Web Service in 3. SOAP is an extensible XML messaging protocol that forms the foundation for Web Services. SOAP provides a simple and consistent mechanism that allows one application to send an XML message to another application. A SOAP message is a one way transmission from a SOAP sender to a SOAP receiver, and any application can participate in an exchange as either sender or receiver. SOAP messages may be combined to support many communication behaviors, including requestresponse, solicit response, one way asynchronous messaging, or event notification. SOAP is a high level protocol that defines only the message structure and a few rules for message processing. It is completely independent of the underlying transport protocol, so SOAP messages can be exchanged over HTTP, JMS, or mail transport protocols. Currently the HTTP protocol is the most frequently used transport for SOAP messages. Well show some sample SOAP messages later in this article. WSDL is an XML document that contains a set of definitions that describes a Web Service. It provides all the information needed to access and use a Web Service. A WSDL document describes what the Web Service does, how it communicates, and where it resides. Workbench User Guide Eclipse platform overview Getting started Basic tutorial The Workbench Editors and views Editors Views. The working group intends to update the value of the Web Services Addressing 1. 0 WSDL Binding namespace URI each time a new version of this document is published. Think about the ideal way to write a web app. Write the code to make it happen. You use the WSDL document at develeopment time to create your service interfaces. Some SOAP implementations, including Systinet WASP, also use WSDL at runtime to support dynamic communications. Installing the software. REQUIREMENTS We assume that you have a Java 1. SDK and a standard HTTP browser installed on your system. The JAVAHOME environment variable should point to your Java 1. SDK installation directory. If you want to follow along with the demo, youll need to download WASP Advanced from Systinet. Unpack the downloaded package to a local disk preferably c and run the install script from the bin subdirectory of the WASP Advanced Advanced installation. In our examples we assume that we have unpacked WASP to the c wasp advanced directory. Youll also need to download the demo sources and unpack it into the c waspdemo directory. If you choose different directory names, please update the env. WASPHOME and WASPDEMO environment variables to point to the WASP installation directory and demo directory respectively. Implementing a simple Web Service. Well follow these steps to create our simple Web Service Create the Web Service business logic. First we need to write a Java class that implements the Web Service business logic. In this case, our business logic will be a simple Java class that simulates a stock quote service. Deploy the Java class to the SOAP server. Next we need to turn the Java class into a Web Service. Well show how to deploy the Java class to a SOAP server using the WASP deployment tool. Generate client access classes. A client application uses a proxy object to access a Web Service. At request time, the proxy accepts a Java method call from the application and translates it into an XML message. At response time, the proxy receives the SOAP reply message, translates it into Java objects, and returns the results to the client application. Client application development. The client application treats the proxy as a standard Java object that facilitates the communication with a Web Service. NOTE Were using MS Windows notation for our commandline commands. If you have a Unix based environment, please make appropriate adjustments to these scripts. So lets start with a simple Java class that implements a stock quote lookup function. Please look at the Java code below NOTE All Java sources mentioned in this example can be found in the src subdirectory of the unpacked demo sources archive. All of them reside in the com. Stock. Quote. Service. Created on Sat 1. Oct 2. 00. 1, 1. 5 2. Simple stock quote service. Stock. Quote. Service. QuoteString symbol. Ignore. CaseSUNW. Ignore. CaseMSFT. Ignore. CaseBEAS. Linked. List get. Available. Stocks. Linked. List list new java. Linked. List. list. SUNW. list. addMSFT. BEAS. return list. Figure 1 Web Service code Stock. Quote. Service. java Our example is yet another simple stock quote system weve seen so many of these, developers should be registered traders by now, but it illustrates how easily Web Services can be created and deployed. In our example, were going to retrieve the price of three stocks BEAS, MSFT, and SUNW. The easiest way to turn our class into a Web Service is to compile our Java classes and then use the deployment tool to deploy them to the Web Services runtime. NOTE Youll find all scripts in the bin subdirectory of the unpacked demo sources archive. NOTE Before running the demo you need to install the Systinet SOAP framework. Please see the Installation chapter of this document for step by step installation. First we start the Web Service runtime server with the startserver. Then we compile Stock. Quote. Service. java and deploy the compiled class to the SOAP server using the deploy. Next we will make sure that everything worked properly by opening the administration console in the HTTP browser. Click on the Refresh button to show a list of all the packages deployed on the server. We should see the Stock. Service package with one Stock. Quote. Service deployed on the server. Notice that the Web Service runtime automatically generated the WSDL file and made it publicly available at http localhost 6. Stock. Quote. Service. Stock. Quote. Service. Namespacehttp idoox. XMLSchema instance. XMLSchema. xmlns ns. SOAP ENChttp schemas. Stock. Quote. Serviceget. QuoteRequest. Stock. Quote. Serviceget. QuoteResponse. Stock. Quote. Serviceget. Available. StocksRequest. Stock. Quote. Serviceget. Available. StocksResponse. Linked. List. Type nameStock. Quote. Service. Available. Stocks. Available. Stocks messagetns Stock. Quote. Serviceget. Available. StocksRequest. Available. Stocks messagetns Stock. Quote. Serviceget. Available. StocksResponse. Quote parameter. Orderp. 0. lt wsdl input nameget. Quote messagetns Stock. Quote. Serviceget. QuoteRequest. Quote messagetns Stock. Quote. Serviceget. QuoteResponse. Type. lt wsdl binding nameStock. Quote. Service typetns Stock. Quote. Service. Available. Stocks. Action stylerpc. Available. Stocks. Stylehttp schemas. Available. Stocks. Stylehttp schemas. Quote. lt soap operation soap. Action stylerpc. Quote. lt soap body useencoded encoding. Stylehttp schemas. Quote. lt soap body useencoded encoding. Stylehttp schemas. Java. Service. Stock. Quote. Service bindingtns Stock. Quote. Service. Stock. Quote. Service. Figure 2 Generated WSDL file Stock. Quote. Service. wsdlThe WSDL file contains a full description of the deployed Web Service. Basically there are three parts in a WSDL file The WHAT part, consisting of the types, message, and port. Type elements, defines the messages and data types exchanged between client and server. A message is the basic communication element of SOAP. A message can consist of one or more parts, each part representing a typed parameter. There are two messages input and output for each method of our stock quote Java class. Since we dont use any complex or compound types in our example, there are no compound type definitions in this WSDL dont worry, well see many of them in future examples. All messages are grouped into operations in an entity called a port. Type. A port. Type represents the interface a concrete set of operations supported by the Web Service. A Web Service can have multiple interfaces represented by different port. Types. Look at the Stock. Quote. Serviceport. Type in the sample WSDL file. It includes two operations get. Available. Stocks and get. Quote. To invoke the get. Quote method, the client sends a Stock. Quoteget. QuoteRequest message. Youll find this message defined earlier in the file. Notice that the Stock. Quoteget. QuoteRequest message consists of one part the input parameter called p. XML Schema string type xsd string. The Web Service is supposed to reply with the Stock. Quoteget. QuoteResponse message, which contains one part the return value called response, which is an XML Schema double type xsd double. The HOW part, consisting of the binding elements, describes the technical implementation details of our Web Service. The binding binds a port. Ontologies and the Semantic Web. Ontologies have become a prominent topic in Computer Science where they serve as explicit conceptual knowledge models that make domain knowledge available to information systems. They play a key role in the vision of the Semantic Web where they provide the semantic vocabulary used to annotate websites in a way meaningful for machine interpretation. As studied in the context of information systems, ontologies borrow from the fields of symbolic knowledge representation in Artificial Intelligence, from formal logic and automated reasoning and from conceptual modeling in Software Engineering, while also building on Web enabling features and standards. Although in Computer Science ontologies are a rather new field of study, certain accomplishments can already be reported from the current situation in ontology research. Web compliant ontology languages based on a thoroughly understood theory of underlying knowledge representation formalisms have been and are being standardized for their widespread use across the Web. Methodological aspects about the engineering of ontologies are being studied, concerning both their manual construction and semiautomated generation. Initiatives on linked open data for collaborative maintenance and evolution of community knowledge based on ontologies emerge, and the first semantic applications of Web based ontology technology are successfully positioned in areas like semantic search, information integration, or Web community portals. This chapter will present ontologies as one of the major cornerstones of Semantic Web technology. It will first explain the notion of formal ontologies in Computer Science and will discuss the range of concrete knowledge models usually subsumed under this label. Next, the chapter surveys ontology engineering methods and tools, both for manual ontology construction and for the automated learning of ontologies from text. Finally, different kinds of usage of ontologies are presented and their benefits in various application scenarios illustrated.
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