IA311 PowerDesigner and XML

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IA311PowerDesigner and XML
Jay Stevens Design Tools Support Manager Internet
Application Division stevensj_at_sybase.com
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PowerDesigner and XML

• Topics
• Introduction to XML
• Introduction to DTDs
• Object Modeling and XML
• PowerDesigner and XML

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Introduction to XML

• The Extensible Markup Language (XML) is the
  universal format for structured documents and
  data on the Web
• The base specifications are XML 1.0, W3C
  Recommendations Feb '98, and Namespaces, Jan '99.

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XML in 7 Points

• XML is a method for putting structured data in a
  text file
• XML looks a bit like HTML but isn't HTML
• XML is text, but isn't meant to be read
• XML is a family of technologies

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XML in 7 Points

• XML is verbose, but that is not a problem
• XML is new, but not that new
• XML is license-free, platform-independent and
  well-supported

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Introduction to XML

• Well-Formed XML Rules
• XML Declaration must begin document
• Elements with data must have both start and end
  tags
• Elements without data using one tag must end with
  /gt
• Must have one element which contains all other
  elements
• Elements may nest but may not overlap
• Attribute values must be quoted
• Characters lt and may only be used to starts
  tags and entity references

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Sample XML file

• Sample XML File

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Introduction to XML

• Valid XML Rules
• A Document Type Definition (DTD) exists
• The XML document conforms to the associated DTD

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Introduction to DTDs

• XML - DTD
• part of XML 1.0 specification
• Element type declarations
• Attribute list declarations
• Entity declarations
• Notation declarations
• Comments
• Recognized by most XML parsers / readers /
  validators

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Sample XML - DTD

• Sample XML - DTD

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Introduction to DTDs

• Problems with DTDs
• Weak Data Typing
• Document Structure is not stored in an XML
  document
• Inheritance is not supported
• Parameter Entities is a cumbersome method to
  accomplish code reuse
• Weak Self-Documentation Facilities

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XML - DTD Alternatives

• XML - Schema
• XML Schema 1.0 is the current working draft being
  evaluated by the World Wide Web Consortium (W3C)
• Used by IBM and Commerce One
• XML - Data
• Note to the W3C XML Schema working committee
• Alternative proposal made mainly by Microsoft
• Used by BizTalk with small modifications
• XML - SOX
• Note to the W3C XML Schema working committee

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XML - DTD Alternatives

• Sample XML - Data
• Sample XML - Schema
• ...

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Object Modeling and XML

• Potential UML to XML mappings
• Classes to Elements
• Attributes to Elements or Attributes
• Attribute properties - datatype, min, max,
  defaults, list of values
• Associations
• Foreign Keys - IDREFs
• Cardinality
• Generalizations - Inheritance
• Extended Elements
• Complex Types

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Object Modeling and XML

• Possible Usage
• Reverse Engineer DTDs
• Documentation and understanding
• Jump start Java development
• Reverse Engineer XML Data files
• Understand structure of XML data file
• Generate DTDs
• Java application may want to persist some classes
  in XML, which would need DTDs.

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PowerDesigner and XML

• Currently supported
• DTD and Schema formats as Object model targets
• XML - DTD
• XML - Data
• XML - Schema
• Mappings - depend on XML target
• Class and Attributes - elements and / or
  attributes
• Attribute properties - element and / or attribute
  definitions
• Associations - migrated foreign key columns
• Generalizations - extended elements

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PowerDesigner and XML

• Reverse Engineering
• Three DTD formats supported
• Success / failure depends on which components of
  the specification are used
• Limited XML data files
• Generation
• Three DTD formats supported

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PowerDesigner and XML

• XML reverse engineering demo
• XML generation demo

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PowerDesigner and XML

• Customizable
• XML environment is very dynamic
• 3 - 7 proposed DTD or Schema formats
• 100s of pre-defined frameworks using one of the
  formats above or a variant
• Object definitions in PowerDesigner are
  customizable
• Alter the behavior of both reverse engineering
  and generation of DTDs

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PowerDesigner and XML

• What can be customized
• Clone our 3 targets to make new targets
• XML - xCBL - variant of XML - Schema
• BizTalk - variant of XML - Data
• ...
• Add Extended attributes
• Support file headers
• Additional attributes for some tags
• ...
• Modify generated syntax for classes and
  attributes
• XML Mapping - map DTD objects to Class diagram

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PowerDesigner and XML

• Object definition editor demo

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PowerDesigner and XML

• Limitations
• Not finalized when the presentation was prepared.

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Conclusion
QUESTIONS ???
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IA311PowerDesigner and XML
Jay Stevens Design Tools Support Manager Internet
Application Division stevensj_at_sybase.com