Data provider

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Revision as of 18:25, 10 February 2012 by Anonymous (talk) (Definition)
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Definition

ODP (Object Data Provider) is a framework that lets you manage bidirectional conversion between instances of GVBuffer and generic objects, the access to the generic objects fields will be execute through OGNL and / or XPath.

Extensions are pre / post processing of data that can be made automatically from the connector before invoking GreenVulcanoESB and / or before returning the result to the caller. Each Data provider contains a field element identify by a key, this fileds are of three type and indicates when an extension has to be applied:

  • INOUT, The Extensions is evaluated on the object set (usually the current GVBuffer, unless otherwise specified by the attribute 'source-selector') the value returned by the expression, is added to the context with the prefix 'key_' + @ key, and set the data provider to be returned in the output.
  • IN, The expression is evaluated on the object set (usually the current GVBuffer, unless otherwise specified by the attribute 'source-selector') the value returned by the expression is added to the context with the prefix 'key_' + @ key.
  • OUT, The expression is evaluated directly on the object that is returned by the DataProvider.

In all cases, two variables are added to the context:

  1. Input: object set, usually the current GVBuffer, which will not be overwritten from attribute 'source-selector';
  2. Output: the object that is returned by the DataProvider.

Following a list of Data provider avaiable:

  • ObjectDataProvider:
  • StringDataProvider
  • MapDataProvider
  • ArrayDataProvider
  • CollectionDataProvider
  • XMLEventCollectionDataProvider
  • InputStreamDataProvider
  • JMSBytesMessageDataProvider
  • JMSMapMessageDataProvider
  • JMSObjectMessageDataProvider
  • JMSStreamMessageDataProvider
  • JMSTextMessageDataProvider
  • Axis2MessageContextDataProvider
  • Axis2SAAJSOAPMessageDataProvider
  • HttpMethodDataProvider

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