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|CodeList||A Cosmos CodeList.|
|CodeListHome||An API class for the CodeListHome Code automatically generated from ARGO/UML|
|IPISDataset||An IPIS Dataset.|
|IPISDatasetHome||An API class for the IPISDatasetHome Code automatically generated from ARGO/UML|
|Row||A Row of data.|
|RowHome||An API class for the RowHome Code automatically generated from ARGO/UML|
|Survey||A Survey is a statisical production process that produces datasets.|
|SurveyHome||An API class for the SurveyHome Code automatically generated from ARGO/UML|
|Value||A Cosmos value.|
|ValueDomain||A Cosmos Value Domain.|
|ValueDomainHome||An API class for the ValueDomainHome Code automatically generated from ARGO/UML|
|ValueHome||An API class for the ValueHome Code automatically generated from ARGO/UML|
|Variable||A Cosmos Variable.|
|VariableHome||An API class for the VariableHome Code automatically generated from ARGO/UML|
Cosmos Model Objects and Cosmos Use Cases Support.
In this document you will find all the information relative to the support for Cosmos Use Cases provided by the Nesstar/Faster project.
The main contribution is a Java implementation of the Cosmos Common API. All the Cosmos Common API classes are contained in this package (nesstar.api.cosmos).
The API provides access to the the minimum subset of the Cosmos object model that it is sufficient to support the use cases. The class supported are included in this object model diagram (classes in light colour are not currently supported by the API). More information on the model is available in the Cosmos Architecture Document.
Before proceeding to the implementation of the use cases you will need to:
The user uses a Registry Client to perform searches in the Registry that will return links to classifications, DDI documents and other objects as required by the other use cases. If the returned object is a Cosmos Object the user can access it and browse it.
The browser used to display the Cosmos objects will be an unmodified Nesstar/Faster Object Browser. This browser dynamically downloads the RDF description of Cosmos classes, that is automatically generated and published on the Web as part of the process of creating the API implementation from the API Model, and use it to dynamically build a user interface that provides access to the object properties and methods.
To invoke the Object Browser the Registry client uses URLs of the form:
<Server-URL> is the URL of the server where the Object Browser is running
<Object-URL> is the URL of the Cosmos/Nesstar object to be displayed by the Object Browser
Note that an Object Browser can be used to browse Cosmos objects anywhere on the Net, not just those hosted on the same server where the Object Browser is running..
More info is avaliable in the Nesstar Administrator Manual.
A registry client is used to query the Cosmos registry to find the URL of a metaware classification.
The URL is then passed to the Mission client that uses the Cosmos Java API to connect to the URL and to get the classification as a set of Java objects.
It then proceeds to convert these objects to its own internal format and display it to the user.
Each classification published by Metaware can be conveniently stored in a single RDF/XML coded file and published using a standard Web Server.
Metaware can create these files in two ways:
Once the classification has been created and published on a Web site, Mission has to access and display it inside its own client. As the Mission Client is written in Java it should be easy to implement this function using the Common API. A commented example of accessing a published classification using the API is implemented is nesstar.example.CosmosClient#classificationBrowsingExample().
For an example of accessing the sample classification through the Faster Object Browser check http://nesstar.essex.ac.uk/browser?FRAMES=true&url=http://www.nesstar.org/sdk/classification.xml
The Mission clients calls a remote IPIS server to perform some statistical operations (merging of two surveys, selection on a variable, conversion of a numerical variable) and displays the operation results.
The steps needed to implement 'live' IPIS objects (to publish and implement the behaviour of the IPISDataset and related objects needed by the use case) are the following:
Once the IPISDatasets have been made available and implemented MISSION has to access them, perform some statistical operation on them and display the results inside its own client. A commented example can be found in nesstar.example.CosmosClient#ipisProcessingExample() .
An IQML user exports some information in DDI format, publish it on the web and register it with the registry (the IQML converter is based on the IQML to Cosmos and Cosmos to DDI mappings).
A (supposedly Faster) user uses the Registry Search client to find the URL of the DDI document.
It then cut and pastes the URL into his Faster Publisher tool and opens it. He then uses the Publisher to authenticate remotely with a Nesstar/Faster Server and to publish it on the server.
The Nesstar Publisher is being extended to:
When the new publisher version is available it will be downloadable from this page.
Legal Notice: All source and executable code made available through this site is, unless otherwise specified, Copyright NSD and it is made available for the sole purpose of research and development in the context of the EU Cosmos project. For any other purpose please contact Simon Musgrave at NSD
For any problem or question relative to these tools please contact: firstname.lastname@example.org.
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