//AServiceImpl.java
/** This file contains an object that is explicitly used by client and servant code to communicate with the service. When the client calls begin() on the service, the service causes a ServiceID specific to the service to be put in the TSC PICurrent slot reserved by this service. When the client calls end() on the service, it sets the TSC slot to a non-valid value to indicate that the service is not in effect. Servants use the verify() method to determine whether the ServiceID was passed from the client side to the server side. 
*/

package pi.serviceexample;

import org.omg.CORBA.Any;
import org.omg.CORBA.TCKind;
import org.omg.CORBA.LocalObject;
import org.omg.CORBA.ORB;
import org.omg.PortableInterceptor.Current;
import org.omg.PortableInterceptor.InvalidSlot;

class AServiceImpl
    extends LocalObject
    implements AService
{
    private int slotId;

    private int currentServiceId = 0;

    private Current piCurrent;

    private Any NOT_IN_EFFECT;

    public AServiceImpl(int slotId)
    {
	this.slotId = slotId;
	NOT_IN_EFFECT = ORB.init().create_any();
    }

    // Package protected so the AService ORBInitializer can access this
    // non-IDL defined method.
    void setPICurrent(Current piCurrent)
    {
	this.piCurrent = piCurrent;
    }

    public void begin()
    {
	Any any = ORB.init().create_any();
	any.insert_long(++currentServiceId);
	setSlot(any);
    }

    public void end()
    {
	setSlot(NOT_IN_EFFECT);
    }

    public void verify()
    {
	try {
	    Any any = piCurrent.get_slot(slotId);
	    if (any.type().kind().equals(TCKind.tk_long)) {
		System.out.println("Service present: " + any.extract_long());
	    } else {
		System.out.println("Service not present");
	    }
	} catch (InvalidSlot e) {
	    System.out.println("Exception handling not shown.");
	}
    }

    // Synchronized because two threads in the same ORB could be
    // sharing this object.
    synchronized private void setSlot(Any any)
    {
	try {
	    piCurrent.set_slot(slotId, any);
	} catch (InvalidSlot e) {
	    System.out.println("Exception handling not shown.");
	}
    }
}