DPML Notify

[mcconnell at BerliOS <mcconnell AT mail.berlios.de>]

Author: mcconnell
Date: 2007-04-16 17:34:11 +0200 (Mon, 16 Apr 2007)
New Revision: 1969

Added:
   trunk/main/MIGRATION.TXT
Log:
add migration info

Added: trunk/main/MIGRATION.TXT
===================================================================
--- trunk/main/MIGRATION.TXT    2007-04-16 15:31:05 UTC (rev 1968)
+++ trunk/main/MIGRATION.TXT    2007-04-16 15:34:11 UTC (rev 1969)
@@ -0,0 +1,55 @@
+DPML SDK 2.0 Migration Notes
+----------------------------
+
+The notes deal with migration from DPML 1.1.0 to DPML 2.0.0.
+
+1. Changes to the Depot index schema and namespace.
+---------------------------------------------------
+
+1.1 Namespace changes
+
+The XML namespace for index files, imported module and imported project 
files has changed from "link:xsd:dpml/lang/dpml-lang#1.0" to the new 
namespace "dpml:library".  This change has been 
+brought about a simpler architecture for new namespace resolution.  Insytead 
of the namespace 
+serving as an implicit resource identifier, version 2.0.0 leverages the 
java.util.ServiceLoader
+to load a schmea validator for any unknown schema references.
+
+1.2 Schema Changes
+
+The schema definition has been simplified with the removal of inline 
declaration of product 
+type datastructures.  For example, under version 1.1 you could define a 
project using the 
+following in-line component type declaration:
+
+  <project name="foo" basedir="foo">
+    <types>
+      <type id="jar"/>
+      <part:plugin class="org.acme.Foo" alias="true"/>
+    </types>
+  </project>
+
+In the above XML sample the declaration of '<part:plugin .../>' is an 
example of an inline 
+declaration.  Under version 2.0.0 the equivalent definition is handled by a 
part type 
+production statement using the new 'source' attribute referencing an XML 
definining a 
+part deployment strategy.
+
+  <project name="foo" basedir="foo">
+    <types>
+      <type id="jar"/>
+      <type id="part" alias="true" source="component.xml"/>
+    </types>
+  </project>
+
+2. Part datatype management changes
+-----------------------------------
+
+2.1 Separation of part schema from strategy schemas.
+
+The schema definition for the 'part' datatype has been updated such that it 
no longer defines any concrete deployment strategies (version 1.1 include 
resource and plagin defintions).  Instead, resource declarations may defined 
under an XML file with a root <resource> element with the namespace 
"dpml:antlib".  Plugin definitions have been removed as these are now 
redundant in that all plugin functionality is fully supported by a 
<component> defintion under the "dpml:metro" namespace.  Under this revised 
structure the introduction of new schemas is much simpler because new 
alternative strategy schemas can be loaded dynamically, as are handlers for 
the strategy type.
+
+2.2 Enhancements to the <context> defintion
+
+The <context> nested element can now include nested context entries, and 
entryies that resolver to map-based structures. The nested context support is 
of particular interest when dealing with 'standard' context interfaces 
declared as return types within an enclosing context interface.  In addition, 
Metro 2.0.0 includes a Context annotation enabling the declaration of an 
interface as a context defintion - enabling the use of alternative interface 
names and improving overall flexibility in context contract specification and 
use.
+
+2.3 Bundled deployment defaults
+
+A deployment profile can not be colocated with a class file under the name 
<classname>.xprofile. The deployment profile contains the declaration of the 
default context and any other component data to be applied on the 
establishment of a component model before subsequent customaization based on 
a component directive within a part datastructure.  In addition, component 
policy (such as lifecycle, lifestyle, etc.) can also be associated with a 
component class via respective annotations.  Collectively these enhancement 
eliminate the need for the metro component ant task (which in turn eliminates 
a significant amount of code and provides a marked performance improvement 
related to component loading and deployment).
+