[jboss-jira] [JBoss JIRA] Commented: (JBRULES-1844) Fluent process API

[ https://jira.jboss.org/jira/browse/JBRULES-1844?page=com.atlassian.jira.p... ] Mauricio Salatino commented on JBRULES-1844: -------------------------------------------- I also update the current documentation in (Please correct my english): drools-docs/drools-docs-flow/src/main/docbook/en-US/Chapter-Flow/Chapter-RuleFlow.xml with: <section> <title>Defining processes using the Process API</title> <para>While it is recommended to define processes using the graphical editor or the underlying XML (to shield yourself from internal APIs), it is also possible to define a process using the Process API directly. The most important process elements are defined in the org.drools.workflow.core and the org.drools.workflow.core.node packages.Note that creating a process using this API can be rather complex and error-prone, and should only be used if the above mentioned methods are not sufficient (for example when automatically generating processes from input that is not XML-based). You can however use the process validator (org.drools.ruleflow.core.validation.RuleFlowProcessValidator) to validate processes that were manually created using the API. </para> <para>Now we are looking some examples about how to build process using the Process API: This is a simple example of a basic process with a ruleset node only: <programlisting> RuleFlowProcessFactory.createProcess("org.drools.HelloWorldRuleSet") .version("1.0") .name("HelloWorldRuleSet") .packageName("org.drools") // nodes .startNode(1).name("Start").done() .ruleSetNode(2) .name("RuleSet") .ruleFlowGroup("someGroup").done() .endNode(3).name("End").done() //Connections .connection(1, 2) .connection(2, 3) //Validate the process structure .validate() //Return the process .done(); </programlisting> </para> <para> You can see that we start calling the static createProcess() method from the RuleFlowProcessFactory class. This method creates a new process instance and then return the RuleFlowProcessFactory that contain that instance. </para> <para> So at this point you can set the version of the process, the name and the package name. Also you can start adding nodes to the current process. If you have autocompletion you can see that you have available all the current supported nodes. </para> <para> When you start adding nodes to the process ,in the example calling the startNode(), ruleSetNode() and endNode() methods, you should see that this methods return a sub class of NodeFactory instance. So at this point you should be able to set the node properties until you call the done() method, that return the current RuleFlowProcessFactory. </para> <para> Notice that when you finised adding nodes you must connect them calling the connection method, this will link your currently added nodes. </para> <para> Then you can validate the generated process calling the validate method. </para> <para> Another interesting example is one with a Split and Join nodes: <programlisting> RuleFlowProcessFactory.createProcess("org.drools.HelloWorldJoinSplit") .version("1.0") .name("HelloWorldJoinSplit") .packageName("org.drools") // nodes .startNode(1).name("Start").done() .split(2).name("Split").type(Split.TYPE_AND).done() .actionNode(3).name("Action 1").action("mvel", "System.out.println(\"Inside Action 1\")").done() .actionNode(4).name("Action 2").action("mvel", "System.out.println(\"Inside Action 2\")").done() .join(5).type(Join.TYPE_AND).done() .endNode(6).name("End").done() //Connections .connection(1, 2) .connection(2, 3) .connection(2, 4) .connection(3, 5) .connection(4, 5) .connection(5, 6) //Validate the process structure .validate() //Return the process .done(); </programlisting> </para> <para> Here we see a simple Split / Join example, the only thing to add here is that you need to pay attention to the connections. Also to understand the behaviour of the Split and Join node you should look at the specified type of each one. </para> <para> Now we can see a more complex example with a foreach node, where we have nested nodes: </para> <para> <programlisting> RuleFlowProcessFactory.createProcess("org.drools.HelloWorldForeach") .version("1.0") .name("HelloWorldForeach") .packageName("org.drools") // nodes .startNode(1).name("Start").done() .foreachNode(2) .linkIncomingConnections(3) .linkOutgoingConnections(3) .collectionExpression("persons") .variable("child", new ObjectDataType("org.drools.Person")) .actionNode(3) .action("mvel", "System.out.println(\"inside the action\")").done() .foreachNodeEnd() .endNode(4).name("End").done() //Connections .connection(1, 2) .connection(2, 4) //Validate the process structure .validate() //Return the process .done(); </programlisting> </para> <para> Here we see how we can include one foreach node with a nested action node. Note the linkIncommingConnections() and linkOutgoingConnections() methods that are called to link the foreach node with the internal action node. This methods must be called before you start adding nodes to this composite node. The same occurs with the collectionExpression() and variable() methods. </para> <para> If you want to add more than one node inside the foreach node you can do it, but you must connect all the nodes inside the foreach node by calling the connection() method inside the foreach node to connect all the internal nodes. This must be done after the nodes inclusion and before the call of the foreachNodeEnd() method. </para> <para> Note that you must call the foreachNodeEnd() method at the end of the nodes definition. </para> </section> -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: https://jira.jboss.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira