Commons SCXML Changes Rahul Akolkar
[03-01-2014] Drop outdated, incomplete, broken or no longer supported features for SCXML 2.0. [09-07-2014] Specification mismatch: event-less transitions are triggered by named events. [01-27-2014] Add support for initial SCXML script (SCXML spec 3.2.2: <scxml> children). [01-27-2014] Support foreach element. [01-27-2014] Check and enforce required scxml element attributes as defined by the specification. [04-03-2014] Groovy expression evaluator. [04-03-2014] Normalize and complete the SCXML object model and parsing. [03-17-2014] Map the <scxml> initial attribute to an initial Transition instead of a (single) TransitionTarget. [03-17-2014] <history> elements (now) requires a <transition> child element with a default target configuration. [04-03-2014] Better separation of concern between SCXMLExecutor and SCInstance and introducing a new SCXMLExecutionContext. [04-03-2014] Redefine SCXMLSemantics to align with the Algorithm for SCXML Interpretation as described in the SCXML specification. [04-03-2014] Support error event raising to comply the spec "3.12.2 Errors". [11-28-2013] Initial state ID attribute in SCXML element shouldn't be mandatory. [12-04-2013] Prevent NPEs for possible null value returned from Evaluator.eval* methods. [12-05-2013] Expose JexlEngine strict/silent mode settings through the JexlEvaluator for easier customization. [10-15-2013] Move to new package and artifact org.apache.commons.scxml2 and version 2.0. [10-14-2013] Test failure in SCXMLWriterTest using Java 7. [10-16-2013] Upgrade JUnit dependency to 4.11. [11-28-2013] SimpleScheduler removes wrong Timer. [06-06-2011] transition leaving a child state of parallel. [01-02-2015] Improve SCXML state configuration handling and optional validation. [11-14-2014] Add support for executing the SCXML IRP test cases. [11-14-2014] Replace JAXP xpath expression evaluation with Commons JXPath. [11-14-2014] Fixing the datamodel handling - reimplement xpath processing, the Data() function and the <assign> action. [10-10-2014] Align <send> action attributes support with the latest SCXML specification. [10-08-2014] Incomplete legal state configuration validation in ModelUpdater. [10-11-2014] Add support for SCXML datamodel type and default Evaluator instantiation. [10-11-2014] Bug in current SCXML specification for addDescendantStatesToEnter algorithm can lead to illegal configurations. [10-17-2013] Rewrite the IO package for version 2.0. [03-30-2014] Support read-only system variables. [01-02-2014] Support _event variable. [01-07-2009] Test case bugs. [04-08-2015] Cancel doesn't work. [07-16-2009] Attribute targettype of send and invoke elements changed to type in SCXML Working Draft (7 May 2009). [04-21-2014] Calculation of states to be entered can be depending on states to be exited and thereby also their possible history. [04-18-2014] State machine running status must be kept and maintained by SCInstance across serialization and deserialization. [12-03-2013] Leave more context (location) information when failing to execute JEXL scripts. [10-16-2013] Improve CustomActionTest not to depend on test method execution order. [11-08-2013] Cast to State in TransitionTargetComparator. [02-13-2015] Preserve order in <send> namelist attribute values. [11-15-2014] Add "null" datamodel support as required by the SCXML specification. [01-09-2009] AbstractStateMachine log error. [01-06-2009] Remove any catch (Throwable t) occurences. [02-15-2014] Drop non-functional exit element. [12-05-2013] Correct error/warning messages in SCXML reading to be up-to-date. [11-01-2013] Support for JEXL2 Evaluator. [03-07-2008] Enable JavaScript as one of the pluggable ELs in SCXML documents. [11-21-2008] Added clirr plugin report, cleaned up some checkstyle errors. [11-21-2008] Support "initial" attribute of <state>. [11-21-2008] SCXMLSerializer does not serialize custom namespace declarations. [11-21-2008] SCXMLSerializer does not serialize custom namespace declarations. [11-21-2008] Change "appLog" name to be derived from "SCXMLSemantics.class" rather than the arbitrary "scxml.app.log" [11-21-2008] "event" attribute of <send> is not evaluated [11-19-2008] Support executable content in <transition> child of <initial> [11-19-2008] Support for <onentry> and <onexit> children for <parallel> states. [11-18-2008] Support for <transition> children for <parallel> states. [11-14-2008] <assign> doesn't remove all existing children from location. [11-14-2008] SCXMLParser should throw an exception for parsing failures on bad URIs in <state>'s "src" attribute. [11-13-2008] Delayed events not passing payload. [11-13-2008] Added Softwaredemo to "Who is using it?" [10-03-2008] Added a tutorial about using Commons SCXML on Google Android. [08-01-2008] Improvements in <send> serialization. [07-30-2008] Stop rendering non-standard "parentid" attribute during serialization. [07-28-2008] Update datamodel section of the guide to stress namespace awareness of document. [07-28-2008] <var> and <exit> should be serialized in the Commons SCXML namespace. [07-28-2008] SCXMLListeners will not processed in defined order. [07-28-2008] Correct semantics for <param> with only the "name" attribute specified. [07-28-2008] Serialization of expressions may produce invalid XML. [07-11-2008] Make TriggerEvent class Serializable. [07-11-2008] <data> should support the "id" attribute. [06-17-2008] The "delay" attribute of the <send> element should be a value expression. [06-17-2008] Support the "initial" attribute of the <scxml> element, added in the 4th Working Draft. [05-03-2008] Better error reporting for ignored or misplaced elements by parser (SCXMLParser class). [04-25-2008] Enhancement request for supporting fragment URLs in <state> element's src attribute. [02-09-2008] Process <parallel> child of <state> correctly. [01-26-2008] Improve first-hit performance for following transitions by working out the paths at parse-time. [01-03-2008] Clarify via Javadocs that the SCXMLParser assumes the input to be a well-formed and correct SCXML document. [01-03-2008] Added tests for SCXML-64. [01-03-2008] Add the issues test package for tracking tests tied to the Commons issue tracker. [01-03-2008] Improve serialization of <transition> elements. [01-03-2008] Add assertPostTriggerState() methods to SCXMLTestHelper. [12-20-2007] Minor site updates: add a prominent download link, and update a few remaining Jakarta references. [12-12-2007] Add experimental Maven2 pom.xml to source distro. [12-12-2007] Update JUnit dependency version to 3.8.2. [12-08-2007] AbstractStateMachine and SimpleSCXMLListener classes switched to the new SCXMLParser. [12-06-2007] Recommended version of Commons Logging has been upgraded to v1.1.1. [12-06-2007] Wild card event name handling on transitions made in line with WD. [12-04-2007] Clarify via class Javadoc interaction model between Invokers and parent executor. [12-04-2007] Add support for the <event> tag. [12-04-2007] Object model not stateless due to State class. Store the completion status for composite states along with other instance information in the executor. [12-04-2007] Deprecate SCXMLDigester class in favor of the new SCXMLParser class. The new class supports newer Working Drafts and has better naming. [12-03-2007] Fix possible race condition in AsyncTrigger class. [12-03-2007] Events from custom actions missing payload. Also fix test classes to safely create contexts. [12-03-2007] Skip serialization tests if necessary directory cannot be created. [11-30-2007] Support nested invokes when using SimpleSCXMLInvoker class. [11-16-2007] Update Maven 2 build to include source and binary assemblies and site resources. [08-20-2007] Apply per region document order filter for transition conflict resolution. See SCXML-52 for part of discussion. [08-06-2007] SimpleSCXMLInvoker may miss transition to final state. [08-01-2007] Fix conflict resolution for conditionless stay transitions. class. [07-30-2007] Various changes related to the Commons TLP move. [07-27-2007] Delete existing child nodes before adding new ones when using <assign> to supply new values to <data> nodes. [06-26-2007] Fixed subclassing behavior for AbstractStateMachine class. [06-15-2007] Better names for getter and setter of the boolean property State#isFinal. Previous names deprecated. [06-15-2007] Added a SCXMLListener abstract adapter class. [06-15-2007] Added information about failing expression to evaluation error messages. [06-14-2007] Remove KEYS file, in favor of one file for all of Commons. [05-29-2007] Payload of events sent to current scxml session using <send> tag are now injected into engine. Commons SCXML adds the special _eventdatamap variable for storing payloads for derived events. [04-25-2007] Replace deprecated API usage, with current ones. [04-25-2007] The test package switched to using SCXMLParser class. [04-25-2007] Added support for <final> to SCXMLParser class. [04-25-2007] Add a Commons SCXML namespace to support implementation specific actions. Moved <var> and <exit> actions to this implementation specific namespace. [03-24-2007] New set of tests matching vocabulary in latest Working Draft, for testing the new SCXMLParser class. [03-24-2007] Deprecate various method in the model package (primarily SCXML, State and Parallel classes) based on changes brought on by the latest WDs. [03-22-2007] Add new parser (org.apache.commons.scxml.io.SCXMLParser) to support latest WD and improve naming. [03-12-2007] The regions of a parallel are entered in document order. This is implementation-specific behavior and users should not rely on it. [03-12-2007] Added tests for conflict resolution based on document order and for multiple transition targets. [03-12-2007] Deprecated various methods in Transition class that refer to a singular target. [03-12-2007] Implement ability to support multiple transition targets (space separated list of state IDs). IDs must no longer contain whitespace. [03-12-2007] Better handling of parent-child relationships (part 1). [03-12-2007] Deprecated State#getTransitions() in favor of State#getTransitionsList(). [03-09-2007] Implement document order priority for transitions. [12-18-2006] SCXMLExecutor#logState() now uses debug level to reduce noise at console. [12-12-2006] target and type attributes of <send> element are now evaluated as expressions. [12-12-2006] Set tests to warn, but not fail, if the DOM L2 implementation in use is not serializable. [12-07-2006] Update Commons Logging to version 1.1. [12-07-2006] Update Commons JEXL to version 1.1. [12-07-2006] Improved processing of namespace prefixes in deferred evaluation of XPath expressions. [12-06-2006] Update Commons Digester to version 1.8. [11-22-2006] Logging for <var> and <assign>. [11-08-2006] Add project DOAP file. [11-07-2006] Add a test case to demonstrate adding a custom action with the same local name as one of the standard SCXML actions (but a different namespace). [11-04-2006] Add tests to ensure white box behavior of the <state> element's src attribute. [10-23-2006] Up to date versions for the usecases blurbs for the website. Update image on site front page. [10-17-2006] Added serial version UIDs. [10-17-2006] New EventDispatcher implementation (SimpleScheduler) that provides the ability to deal with delayed events for the "scxml" <send> type. [10-11-2006] Some thread-safety improvements for SCXMLExecutor instances. [10-11-2006] Update to new ASLv2 license headers for source files. [10-05-2006] The Commons SCXML object model as well as the SCXMLExecutor instances are now serializable. [10-02-2006] Deprecate ErrorReporter fields, add ErrorConstants class for default Commons SCXML semantics. [09-29-2006] Begin the deprecation process for custom digester rules in the io package. [09-21-2006] SCXML elements have to be defined in the following namespace (case sensitive): http://www.w3.org/2005/07/scxml [08-07-2006] Allow the target of a transition to be omitted. [07-28-2006] Updated website to reflect 0.5 release. [07-19-2006] SCXML doesn't compile using (Sun) JDK 1.5. actions. [07-19-2006] Add src attribute processing for assign tag. [06-19-2006] Added invoke, param and finalize processing. These SCXML elements were added in the January 2006 Working Draft. [05-17-2006] Reflect use of JIRA as the issue tracker for Commons SCXML. Bugzilla should no longer be used. [05-17-2006] Added examples of shallow and deep history. [05-17-2006] External document digester now processes custom actions. [05-04-2006] Added section on custom semantics to user guide. [05-04-2006] Added explicit Instructions on core-engine.html from user guide. [05-04-2006] Added datamodel explanation and examples to user guide. [05-04-2006] Added documentation blurb on common interaction patterns using the Commons SCXML library (the "glue" or "bridge" code). [04-24-2006] Commons SCXML has graduated from Commons Sandbox, updated repository to reflect move to Commons Proper. [04-20-2006] Added documentation on "_eventdata" and method invocation in expression languages used. [04-20-2006] Allow SCXML documents using EL to define arbitrary EL functions by providing a FunctionMapper to the ELEvaluator. [04-20-2006] Provide access to SCXMLExecutor's root context. [04-03-2006] Added support for the wildcard (*) event. [04-03-2006] Added _eventdata support. The payload of a triggered event is available under the special variable named _eventdata. [03-28-2006] Unnamed trigger events are now correctly processed (they do not match any event name). [03-23-2006] Initial cut at supporting the datamodel section from the January 06 Working Draft. [03-06-2006] Added a FAQ page for the Commons SCXML website. Added a section on SCXML Contexts and Evaluators (plugging in an expression language) to the online "guide". [03-03-2006] Add support for "target" attribute of "transition" element per the latest (Jan 06) WD. [03-03-2006] Added a Maven2 POM. [03-01-2006] A new usecase for a stand-alone application modeling a stopwatch. [02-28-2006] AbstractStateMachine class added that demonstrates one approach for providing the base functionality needed by standalone classes representing stateful entities, whose behaviors are defined via SCXML documents. [02-27-2006] Improve Commons SCXML website "guide". Added a section on SCXML documents, and another on custom actions. [02-25-2006] Added easier support for custom actions. Provide a "hello world" example using a custom action. [02-25-2006] Refactor processing of actions (they now contain an "execute" method). [02-24-2006] Define ExternalContent interface to mark elements that may contain "body content" (in external namespaces), for example, the SCXML "send" element. [02-22-2006] Minor Javadoc fixes and additions. [02-09-2006] Basic test cases for SCXML document execution when using JEXL as the expression language. [02-09-2006] JexlEvaluator was still assuming a flat context (which was changed on 02-05-2006, see change item below). [02-05-2006] Numerous JUnit test cases added. Start publishing cobertura report. [02-05-2006] Contexts are now created per State, but only as and when needed. The commit message for r374981 has the details. [02-05-2006] The Commons SCXML object model is now decoupled from the SCXML execution engine instance. The Commons SCXML object model is now stateless. For example (incomplete list):
  1. A "SCXML" object no longer contains a root "Context"
  2. A "State" no longer contains a "Context"
  3. A "Transition" no longer contains a list of "SCXMLListeners" attached
  4. A "History" no longer contains the last known configuration.
The advantage of this decoupling is that the SCXML document can be parsed once and reused across multiple execution instances, concurrently or otherwise. [01-22-2006] Package reorganization. Mostly out of discussions on the dev list, three new packages were introduced:
  1. A "test" package for the command line testing utility classes
  2. An "io" package for classes related to reading and writing SCXML documents
  3. A "servlet" environment package for the classes that depend on the servlet API for Commons SCXML usecases in servlet containers.
 [01-11-2006] Various website and documentation improvements. [01-08-2006] Improve dependencies webpage by providing URLs for each. Improve navigation by providing "quick links". [01-08-2006] Added JEXL support for SCXML documents. [01-07-2006] SCXML serialization bits available in a utility class. [12-21-2005] SCXML digester instances are now available for further customization of the default digester ruleset. [12-21-2005] The static digest() methods of the SCXMLDigester class now throw the same exceptions as the underlying ones from Digester#parse(). [12-10-2005] Make digester namespace aware, and capture arbitrary namespace children of SCXML <send> element. [11-17-2005] Site overhaul according to recent discussions on the commons-dev mailing list. [10-18-2005] Decouple SCXML engine from the SCXML execution semantics; make SCXML semantics pluggable. [10-18-2005] Added UML state machine diagrams to the usecases section of the website. [10-14-2005] Added documentation on usecases to website:
  1. Usecase 1: To configure instances of the RDC group container.
  2. Usecase 2: To describe Shale dialogs.
 [10-14-2005] Added API notes to website:
  1. SCXML digester
  2. SCXML engine
  3. Firing events on an SCXML engine
  4. Standalone testing
  5. Fun with EL
 [10-14-2005] Updated dependency information to indicate purpose of dependency (core, test, usecases etc.). [10-14-2005] Added Commons look and feel (navigation bar) to website. [10-10-2005] Added second usecase for Commons SCXML (within ASF projects). Demonstrated the use of SCXML documents for describing Shale dialogs. [10-09-2005] Add a faces package for JSF-based environments (env.faces) [10-09-2005] Updated ant build file to include MyFaces dependency (usecases only). [10-08-2005] Out of the box "simple" interface implementations.
  1. Added simple loggers that implement ErrorHandler, ErrorReporter and SCXMLListener.
  2. Added a SimpleContext that wraps a variables (name to value) Map.
 [10-08-2005] VariableResolver#resolveVariable() should return null if variable is not found instead of throwing an exception (in ELEvaluator.java) [09-29-2005] The scxml.env package has a new child jsp package, to distribute the current contents of the env package such that each supported environment can get its own package in the source. [09-29-2005] Enhanced the Standalone testing functionality to enable:
  1. Value change events on the current Context.
  2. Dummy events to re-evaluate conditionals on event-less transitions.
 [09-15-2005] Now handling outgoing transitions from a Parallel (Section 3.4 SCXML WD). [09-15-2005] Minor Javadoc tweaks. [09-15-2005] "Microwave" test samples reset timer on leaving "cooking" state so state machines can be re-run many times (without a "reset") [09-08-2005] Updated Commons SCXML logo. [08-27-2005] Use a customized set of checkstyle rules. These are the Sun checks with three changes as discussed on the dev list:
  1. Use a regexp header check for ASL
  2. Disable 'hide a field' check (lot of noise from setters)
  3. Disable 'method design for extension' check
 [08-27-2005] Six minor code changes based on FindBugs reports. [08-25-2005] Switch to new ant build file that will work better for the Commons nightlies. [08-24-2005] RootContext (used in the JSP environment) should override ELContext#has(String) method. [08-24-2005] Enhanced couple of samples used by the test cases. [08-23-2005] Added JUnit Test Framework. [08-23-2005] Upgraded Digester version in project dependencies to 1.7. [08-23-2005] Added BeanUtils 1.7.0 dependency as needed by Digester. [08-20-2005] Corrected year of inception in License. [08-20-2005] Corrected some 1500+ checkstyle errors. [08-20-2005] This changes document added. [08-17-2005] Initial SCXML codebase copied from the RDC Taglib codebase (part of Jakarta Taglibs Proper). [08-17-2005] Initial build artifacts, STATUS and PROPOSAL documents.