Chapter 7. Action scripts

Action scripts are pieces of code that define the Script property or the interceptor action of an element. Action scripts can access the global variables, process variables, and predefined variable kcontext. kcontext is an instance of the ProcessContext interface. For more information about kcontext variable, see the ProcessContext Javadoc.

Java and MVEL are supported as dialects for action script definitions. MVEL accepts valid Java code and additionally provides support for nested access to parameters. For example, the MVEL call person.name is equivalent of Java call person.getName().

Example action script in Java and MVEL dialects

// Java dialect
System.out.println(person.getName());

// MVEL dialect
System.out.println(person.name);

You can also use action scripts to view information about process instances. For example, use the following commands to:

  • Return the ID of a process instance: 

    System.out.println(kcontext.getProcessInstance().getId());

  • Return the parent process instance ID if a process instance has a parent: 

    System.out.println(kcontext.getProcessInstance().getParentProcessInstanceId());

  • Return the ID of a process definition related to a process instance: 

    System.out.println(kcontext.getProcessInstance().getProcessId());

  • Return the name of a process definition related to a process instance: 

    System.out.println(kcontext.getProcessInstance().getProcessName());

  • Return the state of a process instance: 

    System.out.println(kcontext.getProcessInstance().getState());

To set a process variable in an action script, use kcontext.setVariable("VARIABLE_NAME", "VALUE").