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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

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 *

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package com.sun.corba.se.impl.oa.poa ;

import java.util.Set ;

import org.omg.CORBA.SystemException ;

import org.omg.PortableServer.ServantActivator ;

import org.omg.PortableServer.Servant ;

import org.omg.PortableServer.ServantManager ;

import org.omg.PortableServer.ForwardRequest ;

import org.omg.PortableServer.POAPackage.WrongPolicy ;

import org.omg.PortableServer.POAPackage.ObjectNotActive ;

import org.omg.PortableServer.POAPackage.ServantNotActive ;

import org.omg.PortableServer.POAPackage.ObjectAlreadyActive ;

import org.omg.PortableServer.POAPackage.ServantAlreadyActive ;

import org.omg.PortableServer.POAPackage.NoServant ;

import com.sun.corba.se.impl.orbutil.concurrent.SyncUtil ;

import com.sun.corba.se.impl.orbutil.ORBUtility ;

import com.sun.corba.se.impl.orbutil.ORBConstants ;

import com.sun.corba.se.impl.oa.NullServantImpl ;

import com.sun.corba.se.impl.javax.rmi.CORBA.Util ;

import com.sun.corba.se.spi.oa.OAInvocationInfo ;

import com.sun.corba.se.spi.oa.NullServant ;

/** Implementation of POARequesHandler that provides policy specific

 * operations on the POA.

 */

public class POAPolicyMediatorImpl_R_USM extends POAPolicyMediatorBase_R {

    protected ServantActivator activator ;

    POAPolicyMediatorImpl_R_USM( Policies policies, POAImpl poa )

    {

        // assert policies.retainServants()

        super( policies, poa ) ;

        activator = null ;

        if (!policies.useServantManager())

            throw poa.invocationWrapper().policyMediatorBadPolicyInFactory() ;

    }

    /* This handles a rather subtle bug (4939892).  The problem is that

     * enter will wait on the entry if it is being etherealized.  When the

     * deferred state transition completes, the entry is no longer in the

     * AOM, and so we need to get a new entry, otherwise activator.incarnate

     * will be called twice, once for the old entry, and again when a new

     * entry is created.  This fix also required extending the FSM StateEngine

     * to allow actions to throw exceptions, and adding a new state in the

     * AOMEntry FSM to detect this condition.

     */

    private AOMEntry enterEntry( ActiveObjectMap.Key key )

    {

        AOMEntry result = null ;

        boolean failed ;

        do {

            failed = false ;

            result = activeObjectMap.get(key) ;

            try {

                result.enter() ;

            } catch (Exception exc) {

                failed = true ;

            }

        } while (failed) ;

        return result ;

    }

    protected java.lang.Object internalGetServant( byte[] id,

        String operation ) throws ForwardRequest

    {

        if (poa.getDebug()) {

            ORBUtility.dprint( this,

                "Calling POAPolicyMediatorImpl_R_USM.internalGetServant " +

                "for poa " + poa + " operation=" + operation ) ;

        }

        try {

            ActiveObjectMap.Key key = new ActiveObjectMap.Key( id ) ;

            AOMEntry entry = enterEntry(key) ;

            java.lang.Object servant = activeObjectMap.getServant( entry ) ;

            if (servant != null) {

                if (poa.getDebug()) {

                    ORBUtility.dprint( this,

                        "internalGetServant: servant already activated" ) ;

                }

                return servant ;

            }

            if (activator == null) {

                if (poa.getDebug()) {

                    ORBUtility.dprint( this,

                        "internalGetServant: no servant activator in POA" ) ;

                }

                entry.incarnateFailure() ;

                throw poa.invocationWrapper().poaNoServantManager() ;

            }

            // Drop the POA lock during the incarnate call and

            // re-acquire it afterwards.  The entry state machine

            // prevents more than one thread from executing the

            // incarnate method at a time within the same POA.

            try {

                if (poa.getDebug()) {

                    ORBUtility.dprint( this,

                        "internalGetServant: upcall to incarnate" ) ;

                }

                poa.unlock() ;

                servant = activator.incarnate(id, poa);

                if (servant == null)

                    servant = new NullServantImpl(

                        poa.omgInvocationWrapper().nullServantReturned() ) ;

            } catch (ForwardRequest freq) {

                if (poa.getDebug()) {

                    ORBUtility.dprint( this,

                        "internalGetServant: incarnate threw ForwardRequest" ) ;

                }

                throw freq ;

            } catch (SystemException exc) {

                if (poa.getDebug()) {

                    ORBUtility.dprint( this,

                        "internalGetServant: incarnate threw SystemException " + exc ) ;

                }

                throw exc ;

            } catch (Throwable exc) {

                if (poa.getDebug()) {

                    ORBUtility.dprint( this,

                        "internalGetServant: incarnate threw Throwable " + exc ) ;

                }

                throw poa.invocationWrapper().poaServantActivatorLookupFailed(

                    exc ) ;

            } finally {

                poa.lock() ;

                // servant == null means incarnate threw an exception,

                // while servant instanceof NullServant means incarnate returned a

                // null servant.  Either case is an incarnate failure to the

                // entry state machine.

                if ((servant == null) || (servant instanceof NullServant)) {

                    if (poa.getDebug()) {

                        ORBUtility.dprint( this,

                            "internalGetServant: incarnate failed" ) ;

                    }

                    // XXX Does the AOM leak in this case? Yes,

                    // but the problem is hard to fix.  There may be

                    // a number of threads waiting for the state to change

                    // from INCARN to something else, which is VALID or

                    // INVALID, depending on the incarnate result.

                    // The activeObjectMap.get() call above creates an

                    // ActiveObjectMap.Entry if one does not already exist,

                    // and stores it in the keyToEntry map in the AOM.

                    entry.incarnateFailure() ;

                } else {

                    // here check for unique_id policy, and if the servant

                    // is already registered for a different ID, then throw

                    // OBJ_ADAPTER exception, else activate it. Section 11.3.5.1

                    // 99-10-07.pdf

                    if (isUnique) {

                        // check if the servant already is associated with some id

                        if (activeObjectMap.contains((Servant)servant)) {

                            if (poa.getDebug()) {

                                ORBUtility.dprint( this,

                                    "internalGetServant: servant already assigned to ID" ) ;

                            }

                            entry.incarnateFailure() ;

                            throw poa.invocationWrapper().poaServantNotUnique() ;

                        }

                    }

                    if (poa.getDebug()) {

                        ORBUtility.dprint( this,

                            "internalGetServant: incarnate complete" ) ;

                    }

                    entry.incarnateComplete() ;

                    activateServant(key, entry, (Servant)servant);

                }

            }

            return servant ;

        } finally {

            if (poa.getDebug()) {

                ORBUtility.dprint( this,

                    "Exiting POAPolicyMediatorImpl_R_USM.internalGetServant " +

                    "for poa " + poa ) ;

            }

        }

    }

    public void returnServant()

    {

        OAInvocationInfo info = orb.peekInvocationInfo();

        byte[] id = info.id() ;

        ActiveObjectMap.Key key = new ActiveObjectMap.Key( id ) ;

        AOMEntry entry = activeObjectMap.get( key ) ;

        entry.exit() ;

    }

    public void etherealizeAll()

    {

        if (activator != null)  {

            Set keySet = activeObjectMap.keySet() ;

            // Copy the elements in the set to an array to avoid

            // changes in the set due to concurrent modification

            ActiveObjectMap.Key[] keys =

                (ActiveObjectMap.Key[])keySet.toArray(

                    new ActiveObjectMap.Key[ keySet.size() ] ) ;

            for (int ctr=0; ctr<keySet.size(); ctr++) {

                ActiveObjectMap.Key key = keys[ctr] ;

                AOMEntry entry = activeObjectMap.get( key ) ;

                Servant servant = activeObjectMap.getServant( entry ) ;

                if (servant != null) {

                    boolean remainingActivations =

                        activeObjectMap.hasMultipleIDs(entry) ;

                    // Here we etherealize in the thread that called this

                    // method, rather than etherealizing in a new thread

                    // as in the deactivate case.  We still inform the

                    // entry state machine so that only one thread at a

                    // time can call the etherealize method.

                    entry.startEtherealize( null ) ;

                    try {

                        poa.unlock() ;

                        try {

                            activator.etherealize(key.id, poa, servant, true,

                                remainingActivations);

                        } catch (Exception exc) {

                            // ignore all exceptions

                        }

                    } finally {

                        poa.lock() ;

                        entry.etherealizeComplete() ;

                    }

                }

            }

        }

    }

    public ServantManager getServantManager() throws WrongPolicy

    {

        return activator;

    }

    public void setServantManager(

        ServantManager servantManager ) throws WrongPolicy

    {

        if (activator != null)

            throw poa.invocationWrapper().servantManagerAlreadySet() ;

        if (servantManager instanceof ServantActivator)

            activator = (ServantActivator)servantManager;

        else

            throw poa.invocationWrapper().servantManagerBadType() ;

    }

    public Servant getDefaultServant() throws NoServant, WrongPolicy

    {

        throw new WrongPolicy();

    }

    public void setDefaultServant( Servant servant ) throws WrongPolicy

    {

        throw new WrongPolicy();

    }

        private POAPolicyMediatorImpl_R_USM mediator ;

        private ActiveObjectMap.Key key ;

        private AOMEntry entry ;

        private Servant servant ;

        private boolean debug ;

        public Etherealizer( POAPolicyMediatorImpl_R_USM mediator,

            ActiveObjectMap.Key key, AOMEntry entry, Servant servant,

            boolean debug )

        {

            this.mediator = mediator ;

            this.key = key ;

            this.entry = entry;

            this.servant = servant;

            this.debug = debug ;

        }

        public void run() {

            if (debug) {

                ORBUtility.dprint( this, "Calling Etherealizer.run on key " +

                    key ) ;

            }

            try {

                try {

                    mediator.activator.etherealize( key.id, mediator.poa, servant,

                        false, mediator.activeObjectMap.hasMultipleIDs( entry ) );

                } catch (Exception exc) {

                    // ignore all exceptions

                }

                try {

                    mediator.poa.lock() ;

                    entry.etherealizeComplete() ;

                    mediator.activeObjectMap.remove( key ) ;

                    POAManagerImpl pm = (POAManagerImpl)mediator.poa.the_POAManager() ;

                    POAFactory factory = pm.getFactory() ;

                    factory.unregisterPOAForServant( mediator.poa, servant);

                } finally {

                    mediator.poa.unlock() ;

                }

            } finally {

                if (debug) {

                    ORBUtility.dprint( this, "Exiting Etherealizer.run" ) ;

                }

            }

        }

    }

    public void deactivateHelper( ActiveObjectMap.Key key, AOMEntry entry,

        Servant servant ) throws ObjectNotActive, WrongPolicy

    {

        if (activator == null)

            throw poa.invocationWrapper().poaNoServantManager() ;

        Etherealizer eth = new Etherealizer( this, key, entry, servant, poa.getDebug() ) ;

        entry.startEtherealize( eth ) ;

    }

    public Servant idToServant( byte[] id )

        throws WrongPolicy, ObjectNotActive

    {

        ActiveObjectMap.Key key = new ActiveObjectMap.Key( id ) ;

        AOMEntry entry = activeObjectMap.get(key);

        Servant servant = activeObjectMap.getServant( entry ) ;

        if (servant != null)

            return servant ;

        else

            throw new ObjectNotActive() ;

    }

}