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| − | <div style="float:right;border:1px solid #000000;padding:5px;max-width:500px;">__TOC__</div>
| + | For the current version, see: |
| − | ==EclipseLink DBWS Overview==
| + | '''[http://www.eclipse.org/eclipselink/documentation/2.4/dbws/toc.htm Developing Persistence Architectures Using EclipseLink Database Web Services, Release 2.4]''' |
| − | The goal of EclipseLink DBWS is to enable simple and efficient access to relational database artifacts via a Web service, extending EclipseLink's core capabilities while leveraging existing components (ORM, OXM).
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| − | EclipseLink DBWS has two parts: a design-time tooling component and a runtime provider component that takes a service descriptor (along with related deployment artifacts) and realizes it as a JAX-WS 2.0 Web service. The runtime provider uses EclipseLink to bridge between the database and the XML SOAP Messages used by Web service clients.
| + | For EclispeLink DBWS Overview, see http://www.eclipse.org/eclipselink/documentation/2.4/dbws/overview.htm |
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| − | An EclipseLink DBWS service may be comprised of any number of '''operations''' of which there are 4 types:
| + | [[Category:DBWS]] |
| − | # Insert - inserts into the database persistent entities described by an XML document.
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| − | # Update - updates database persistent entities described by an XML document.
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| − | # Delete - removes from the database persistent entities described by an XML document.
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| − | # Query - retrieves from the database persistent entities described by an XML document. <br>Selection criteria for Query operations can be specified by:
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| − | #* custom <tt>SQL</tt>
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| − | #* Stored Procedures
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| − | #* EclipseLink Named Queries (can use the complete range of EclipseLink ORM Expression Framework APIs)
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| − | The XML documents used by an '''operation''' conform to an XML Schema Definition (<tt>.xsd</tt> file) auto-generated by the design-time tooling. Alternatively, if no <tt>.xsd</tt> is available, a pre-defined simple XML format (SXF) is used.
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| − | ===Concept: XML-to-Relational Mapping (XRM)===
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| − | EclipseLink's ORM and OXM features provides the basis for a powerful '''bridge''' between a database's relational structure(s) and XML's hierarchical structure.
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| − | [[Image:XRRunTime.png]] | + | |
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| − | ===Configuration===
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| − | The metadata for an EclipseLink DBWS service is contained in an easy-to-read service descriptor file <b>eclipselink-dbws.xml</b>:
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| − | * contains <b><i>name of EclipseLink DBWS service</i></b>
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| − | * contains <b><i>name of sessions.xml</i></b> - if not present, then <tt><b>eclipselink-dbws-sessions.xml</b></tt> will be used
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| − | * operation definitions
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| − | * contains <b><tt>eclipselink-dbws-schema.xsd</tt></b> XML Schema Definition file
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| − | Example DBWS Service descriptor file
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| − | <source lang="xml">
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| − | <?xml version="1.0" encoding="UTF-8"?>
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| − | <dbws
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| − | xmlns:xsd="http://www.w3.org/2001/XMLSchema"
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| − | xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
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| − | >
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| − | <name>example</name>
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| − | <query>
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| − | <name>countEmployees
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| − | <result>
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| − | <type>xsd:int</type>
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| − | </result>
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| − | <sql><![CDATA[select count(*) from EMP]]></sql>
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| − | </query>
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| − | </dbws>
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| − | </source>
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| − | The information required by the EclipseLink DBWS service descriptor file is kept to a minimum and omitted fields have simple defaults, allowing for both auto-generation by tools or manual editing.
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| − | ===XML Schema Definition===
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| − | An EclipseLink DBWS service requires an XML Schema Definition file to specify how information returned from the database is to be shaped. The EclipseLink OXM Project handles converting information from the database to XML, giving the user access to the complete range of EclipseLink Object-to-XML mapping capabilities. If no schema is provided by the user, a pre-defined Simple XML Format (SXF) can be used.
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| − | <blockquote style="padding:4px;border:1px solid black;">
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| − | SXF uses information only available at the time of query execution to build the XML element-tag names; thus, these XML documents cannot be validated against any schema.
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| − | </blockquote>
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| − | ===Auto-generation of An EclipseLink DBWS service===
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| − | The design-time tooling will auto-generate a DBWS service, creating the service descriptor and all required deployment artifacts.
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