/*
 * @(#)LocalClientRequestDispatcherBase.java	1.15 03/12/19
 *
 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package com.sun.corba.se.impl.protocol;

import org.omg.CORBA.portable.ServantObject;

import com.sun.corba.se.spi.protocol.LocalClientRequestDispatcher;
import com.sun.corba.se.spi.protocol.RequestDispatcherRegistry;

import com.sun.corba.se.spi.orb.ORB;
import com.sun.corba.se.spi.ior.IOR ;
import com.sun.corba.se.spi.oa.ObjectAdapterFactory;

import com.sun.corba.se.spi.ior.ObjectAdapterId;
import com.sun.corba.se.spi.ior.TaggedProfile;
import com.sun.corba.se.spi.ior.ObjectKeyTemplate;
import com.sun.corba.se.spi.ior.ObjectId; 

public abstract class LocalClientRequestDispatcherBase implements LocalClientRequestDispatcher
{
    protected ORB orb;
    int scid;

    // Cached information needed for local dispatch
    protected boolean servantIsLocal ;
    protected ObjectAdapterFactory oaf ;
    protected ObjectAdapterId oaid ;
    protected byte[] objectId ;

    // If isNextIsLocalValid.get() == Boolean.TRUE, 
    // the next call to isLocal should be valid
    protected static ThreadLocal isNextCallValid = new ThreadLocal() {
	    protected synchronized Object initialValue() {
		return Boolean.TRUE;
	    }
	};

    protected LocalClientRequestDispatcherBase(ORB orb, int scid, IOR ior)
    {
	this.orb = orb ;

	TaggedProfile prof = ior.getProfile() ;
	servantIsLocal = orb.getORBData().isLocalOptimizationAllowed() && 
	    prof.isLocal();

	ObjectKeyTemplate oktemp = prof.getObjectKeyTemplate() ;
	this.scid = oktemp.getSubcontractId() ;
	RequestDispatcherRegistry sreg = orb.getRequestDispatcherRegistry() ;
	oaf = sreg.getObjectAdapterFactory( scid ) ;
	oaid = oktemp.getObjectAdapterId() ;
	ObjectId oid = prof.getObjectId() ;
	objectId = oid.getId() ;
    }

    public byte[] getObjectId() 
    {
	return objectId ;
    }

    public boolean is_local(org.omg.CORBA.Object self)
    {
	return false;
    }

    /*
    * Possible paths through
    * useLocalInvocation/servant_preinvoke/servant_postinvoke:
    *
    * A: call useLocalInvocation
    * If useLocalInvocation returns false, servant_preinvoke is not called.
    * If useLocalInvocation returns true,
    * call servant_preinvoke
    *	If servant_preinvoke returns null,
    *	    goto A
    *   else
    *	    (local invocation proceeds normally)
    *	    servant_postinvoke is called
    *
    */
    public boolean useLocalInvocation( org.omg.CORBA.Object self ) 
    {
	if (isNextCallValid.get() == Boolean.TRUE)
	    return servantIsLocal ;
	else
	    isNextCallValid.set( Boolean.TRUE ) ;

	return false ;    
    }

    /** Check that the servant in info (which must not be null) is
    * an instance of the expectedType.  If not, set the thread local flag
    * and return false.
    */
    protected boolean checkForCompatibleServant( ServantObject so, 
	Class expectedType )
    {
	if (so == null)
	    return false ;

	// Normally, this test will never fail.  However, if the servant
	// and the stub were loaded in different class loaders, this test
	// will fail.
	if (!expectedType.isInstance( so.servant )) {
	    isNextCallValid.set( Boolean.FALSE ) ;

	    // When servant_preinvoke returns null, the stub will
	    // recursively re-invoke itself.  Thus, the next call made from 
	    // the stub is another useLocalInvocation call.
	    return false ;
	}

	return true ;
    }

}

// End of file.