WebSphere Adapter for JDBC
The adapter is globalized to support single- and multi-byte character sets and deliver message text in the specified language. The adapter also performs bidirectional transformation, which refers to the task of processing data that contains both left-to-right (Hebrew or Arabic, for example) and right-to-left (a URL or file path, for example) semantic content within the same file.
The Java™ runtime environment within the Java virtual machine (JVM) represents data in the Unicode character code set. Unicode contains encodings for characters in most known character code sets (both single- and multi-byte). Components in the WebSphere® Business Integration system are written in Java. Therefore, when data is transferred between WebSphere Business Integration system components, there is no need for character conversion.
To log error and informational messages in the appropriate language and for the appropriate country or region, the adapter uses the locale of the system on which it is running.
Languages such as Arabic and Hebrew are written from right to left, yet they contain embedded segments of text that are written left to right, resulting in bidirectional script. When software applications handle bidirectional script, standards are used to display and process it. WebSphere Process Server and WebSphere Enterprise Service Bus use the Windows® standard format, but an enterprise information system exchanging data with WebSphere Process Server or WebSphere Enterprise Service Bus can use a different format. WebSphere Adapters transform bidirectional script data passed between the two systems so that it is accurately processed and displayed on both sides of a transaction.
Bidirectional format
WebSphere Process Server and WebSphere Enterprise Service Bus use the bidirectional format of ILYNN (implicit, left-to-right, on, off, nominal). This is the format used by Windows. If an enterprise information system uses a different format, the adapter converts the format prior to introducing the data to WebSphere Process Server or WebSphere Enterprise Service Bus.
Five attributes comprise bidirectional format. When you set bidirectional properties, you assign values for each of these attributes. The attributes and settings are listed in the following table.
Letter position | Purpose | Values | Description | Default setting |
---|---|---|---|---|
1 | Order schema | I or V | Implicit (Logical) or Visual | I |
2 | Direction | L R C D |
Left-to-Right, Right-to-Left Contextual Left-to-Right Contextual Right-to-Left |
L |
3 | Symmetric Swapping | Y or N | Symmetric Swapping is on or off | Y |
4 | Shaping | S N I M F B |
Text is shaped Text is not shaped Initial shaping Middle shaping Final shaping Isolated shaping |
N |
5 | Numeric Shaping | H C N |
Hindi Contextual Nominal |
N |
The adapter transforms data into a logical, left-to-right format before sending the data to WebSphere Process Server or WebSphere Enterprise Service Bus.
Using bidirectional properties
You can use multiple bidirectional properties to control the transformation of both content data and metadata. You can set special bidirectional properties to exclude either content data or metadata from bidirectional transformation, or to identify data that requires special treatment during a transformation.
The following table describes four types of bidirectional properties.
Property type | Data transformations |
---|---|
EIS | Controls the format for content data, or data that is sent by the enterprise information system. |
Metadata | Controls the format for metadata, or data that provides information about the content data. |
Skip | Identifies content or metadata to exclude from transformation. |
Special Format | Identifies certain text, such as file paths or URLs, that require different treatment during the transformation process. Can be set for either content data or metadata. |
You can set properties that control bidirectional transformation in three areas.
Business object annotations
Some adapters allow you to annotate bidirectional properties within a business object. Do this to add information that specifically controls the transformation of a business object or part of a business object. Use business object editor, a tool within WebSphere Integration Developer, to add annotations at these levels:
Property scope and lookup mechanism
After you set values for bidirectional properties for an adapter and annotate business objects where appropriate, the adapter performs bidirectional transformations. It does so by using logic that relies on a hierarchical inheritance of property settings and a lookup mechanism.
Properties defined within the resource adapter are at the top of the hierarchy, while those defined within other areas or annotated within a business object are at lower levels of the hierarchy. So for example, if you only set values for EIS-type bidirectional properties for the resource adapter, those values are inherited and used by transformations that require a defined EIS-type bidirectional property whether they arise from an inbound (activation specification) transaction or an outbound (managed connection factory) transaction.
However, if you set values for EIS-type bidirectional properties for both the resource adapter and the activation specification, a transformation arising from an inbound transaction uses the values set for the activation specification.
The processing logic uses a lookup mechanism to search for bidirectional property values to use during a transformation. The lookup mechanism begins its search at the level where the transformation arises and searches upward through the hierarchy for defined values of the appropriate property type. It uses the first valid value it finds. It searches the hierarchy from child to parent only; siblings are not considered in the search.
Last updated: Tue 12 Dec 2006 03:32:38
(c) Copyright IBM Corporation 2005, 2006.
This information center is powered by Eclipse technology (http://www.eclipse.org)