Version 2.0.0 is the latest production stable build of the DPML platform. It incorporates a number of important functional enhancements over the 1.X series brought about through an internal restructuring of the component deployment architecture. The 2.0.0 version has a structural dependency on the Java 1.6 platform. Semantics of component deployment such as Context definition remain backward compatible with the 1.X series. Internal APIs have changed relative to 1.X to better align with draft JSR 277 module specifications.
Key features incorporated into the 2.0.0 release include:
- JSR 277 readiness.
- Integral support for java.util.ServiceLoader as a basic extension mechansims.
- Support for plugable content type handlers via java.util.ServiceLoader.
- JMX management of the Transit resource management layer.
- Metro component model moved to a dedicated content type handler.
- Support for nested contect interface defintions.
- Context model suport for map datatypes.
- Support for uri fragment argument handling.
- Improved part interface semantics.
- Improved XSD namespace management.
- Package namespace updates to facilitate improved private class isolation.
- Comprehansive updates to tutorials and online documentation.
- Improvements to Station deployment metadata.
- Reduced platform footprint.
The 1.1.0 release includes a number of small updates dealing with runtime support for Java 1.5 and 1.6. The changes deal with memory management under 1.5 and 1.6 that introduce requirements for a more restricted component decommissioning process. Other changes include the addition of the support for symbolic property references inside part definitions declared at the level of a Depot project type declaration.
The 1.0.3 update is a general maintenance release that incorporates updates to the Transit artifact protocol handler and related Ant tools. The distribution also includes numerouse documentation enhancements.
The 1.0.2 release includes the resolution of a bug in the Transit console handler related to the deployment of plugins from the command line. Earlier versions did not properly support plugins declaring a net.dpml.util.Logger constructor argument instance. The release also includes improvements to the console info listing with additional version information for both console and runtime resources.
Changes in this release include the addition of a new command-line option to the Depot build tool enabling a decimal version build policy together with some internal implementation enhancements that enable the generation of a full DPML system build using the Depot build system. The decimal versioning option basically addresses functional requirements that arise when evaluating the impact of small changes on dependent systems. In addition version 1.0.1 introduces the ability within the DPML build to run the entire build under Depot (as opposed to the earlier bootstrap+Depot build sequence). With full Depot-based build sequencing in place its now much easier to address subjects such as build system reporting and general shortcomings in larger scale multi-project management.
The DPML is proud to announce the formal distribution of version 1.0.0 of the DPML SDK.
| Transit | Transit is a resource management system that lets you work with uris instead of urls - where uris include artifact:[group]/[name]#[version] (for cached based retrieval of versioned resources backed by local and/or remote repositories), link:[group]/[name]#[version] which provides an equivalent concept to a symlink, and local:[group]/[name]#[version] for retrieval of local preferences. Above the resource management layer is a plugin management system that combines 'deployment data' and 'classloader chain' information into XML files that can be used by the system to automatically deploy complex systems. |
| Metro | Metro is an advanced deployment strategy for plugins. In effect Transit plugin definitions allow for the declaration of alternative object deployment strategies. While the basic Transit plugin model supports a generic framework (including antlib resources loading) - the Metro system goes orders of magnitude further in its provision for lifecycle management, custom lifestyle, Context-IOC, remote management, logging, and other features aimed at composite component management. The Metro platform also includes a the 'Station' - in effect a server handles multiple JVMs and provides support for remote application management. |
| Depot | The Depot library provides a framework for <resource> (e.g. jar file, XML files, etc.), <project>, and <module> declarations. Modules identify a namespace for a group of resource and/or projects. Projects identify a working base directory. Projects can declare scoped dependencies covering BUILD, TEST and RUNTIME phases. Runtime phases can be further qualified to separate PUBLIC, PROTECTED and PRIVATE scopes. In addition project definitions may include property and filter declarations and (which may be direct name/token substitution or feature based substitution - e.g. lookup the version of project X and replace token Y with the value). The build system includes a command line handler that uses the library to resolve project base directories, transitive dependencies, properties, and filters. It uses the Transit system for all resource management concerns including support within Transit for the declaration and deployment of plugins (where a plugin is somewhat equivalent to an antlib plus classloader definition). Depot uses Transit for loading build templates and antlibs. Depot also includes a small number of Ant tasks that enable build automation of the majority of the DPML project. Generally speaking these ant tasks are simply pulling in info from the library (e.g. compile path creation, test path creation, meta-data creation, property resolution, etc.). When the generic Depot tasks don't meet all of our needs - we simply add extra extra instructions into build.xml files (i.e. its just driving classic Ant). |