Restarting the Java Stack of an SAP NetWeaver Dual-Stack System 
With a dual stack system, a Java instance is assigned to an ABAP instance. The Internet Communication Manager (ICM) of the ABAP instance starts and stops the associated Java instance as required.
Proceed as follows to restart the Java stack of your SAP NetWeaver dual-stack (ABAP + Java) system:
Log on to the ABAP stack of SAP NetWeaver.
Open the list of SAP servers by calling transaction SM51.
Double-click the instance for which you want to restart the Java stack.
You are now connected to the selected instance.
Start the ICM Monitor (transaction SMICM) by entering /nSMICM in the command field.
In transaction SMICM, choose .
The corresponding SAP NetWeaver Java stack for your instance is stopped and restarted.