The Imixs-Workflow Engine

The Imixs-Workflow engine is the core service inside the Imixs-Workflow technology. The Imixs-Workflow engine is an transactional robust service component to process business data objects based on a BPMN 2.0 model.

After you have defined your business model with Imixs-BPMN you can create a new data object - called workitem - to process it with the Imixs-Workflow engine. After processing a workitem by the workflow engine, the workitem becomes a process instance of the current workflow. From this moment the workflow engine controls the workitem until the business process is completed.

Create a new Process Instance

To start a new process instance, you must first create a new workitem and assign it to an existing model. Next you can add any business data to this data object and process it by calling the method processWorkItem(). The Imixs-Workflow Engine is an EJB service component which you can inject into your code. See the following example code:

import org.imixs.workflow.ItemCollection;
.....
@EJB
private org.imixs.workflow.engine.WorkflowService workflowService;
....
// create a new workitem assigned to a workflow model
ItemCollection workitem=new ItemCollection().model("1.0.0").task(100).event(10);
// assign business data
workitem.setItemValue("_customer","M. Melman");
workitem.setItemValue("_ordernumber",20051234);
// process the workitem
workitem = workflowService.processWorkItem(workitem);

After you have processed a Workitem you can evaluate the workflow data, provided by the workflow engine: 

....
// get the assigend workitem unique id...
String uniqueID=workitem.getUnqiueID();
// read the current workflow status
String status=workitem.getItemValueString(WorkflowKernel.WORKFLOWSTATUS);
....

With the uniqueID which is automatically assigend to a workitem, you can fetch the process instance later from by WorkflowService:

....
// load a process instance by the unique id...
workitem=workflowService.getWorkItem(uniqueid);
....

You can also request different lists of workitems by calling the corresponding get method: 

....
// get all workitems for the current user...
List<ItemCollection> tasklist = workflowService.getWorkListByOwner(null, null, 30, 0, null, false);
....

The Imixs WorkflowServce provides various methods to manage workitems processed by the workflow engine. See the workflow engine section for more details.