You can expose a synchronous interface in the front end while using an asynchronous callback in the back end to simulate a synchronous reply. This is the default behavior in BPEL processes with the automatic setting of the bpel.config.transaction property to requiresNew in the composite.xml file. The following example provides details.

<component name="BPELProcess1"> 
  <implementation.bpel src="BPELProcess1.bpel"/> 
  <property name="bpel.config.transaction" type="xs:string" 
  many="false">requiresNew</property> 
  </component> 

The requiresNew value is recommended. If you want to participate in the client's transaction, you must set the bpel.config.transaction property to required.