/*
 * Copyright (c) 1998, 2013, Oracle and/or its affiliates. All rights reserved.
 * 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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 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package java.beans.beancontext;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;

import java.util.TooManyListenersException;

import java.util.Locale;


This helper class provides a utility implementation of the
java.beans.beancontext.BeanContextServices interface.


Since this class directly implements the BeanContextServices interface,
the class can, and is intended to be used either by subclassing this
implementation, or via delegation of an instance of this class
from another through the BeanContextProxy interface.

Author:
Laurence P. G. Cable
Since:
1.2/**
 * <p>
 * This helper class provides a utility implementation of the
 * java.beans.beancontext.BeanContextServices interface.
 * </p>
 * <p>
 * Since this class directly implements the BeanContextServices interface,
 * the class can, and is intended to be used either by subclassing this
 * implementation, or via delegation of an instance of this class
 * from another through the BeanContextProxy interface.
 * </p>
 *
 * @author Laurence P. G. Cable
 * @since 1.2
 */

public class      BeanContextServicesSupport extends BeanContextSupport
       implements BeanContextServices {
    private static final long serialVersionUID = -8494482757288719206L;

    

Construct a BeanContextServicesSupport instance

Params:
peer –      The peer BeanContext we are supplying an implementation for, if null the this object is its own peer
lcle –      The current Locale for this BeanContext.
dTime –     The initial state, true if in design mode, false if runtime.
visible –   The initial visibility./**
     * <p>
     * Construct a BeanContextServicesSupport instance
     * </p>
     *
     * @param peer      The peer BeanContext we are supplying an implementation for, if null the this object is its own peer
     * @param lcle      The current Locale for this BeanContext.
     * @param dTime     The initial state, true if in design mode, false if runtime.
     * @param visible   The initial visibility.
     *
     */

    public BeanContextServicesSupport(BeanContextServices peer, Locale lcle, boolean dTime, boolean visible) {
        super(peer, lcle, dTime, visible);
    }

    
Create an instance using the specified Locale and design mode.
Params:
peer –      The peer BeanContext we are supplying an implementation for, if null the this object is its own peer
lcle –      The current Locale for this BeanContext.
dtime –     The initial state, true if in design mode, false if runtime./**
     * Create an instance using the specified Locale and design mode.
     *
     * @param peer      The peer BeanContext we are supplying an implementation for, if null the this object is its own peer
     * @param lcle      The current Locale for this BeanContext.
     * @param dtime     The initial state, true if in design mode, false if runtime.
     */

    public BeanContextServicesSupport(BeanContextServices peer, Locale lcle, boolean dtime) {
        this (peer, lcle, dtime, true);
    }

    
Create an instance using the specified locale
Params:
peer –      The peer BeanContext we are supplying an implementation for, if null the this object is its own peer
lcle –      The current Locale for this BeanContext./**
     * Create an instance using the specified locale
     *
     * @param peer      The peer BeanContext we are supplying an implementation for, if null the this object is its own peer
     * @param lcle      The current Locale for this BeanContext.
     */

    public BeanContextServicesSupport(BeanContextServices peer, Locale lcle) {
        this (peer, lcle, false, true);
    }

    
Create an instance with a peer
Params:
peer –      The peer BeanContext we are supplying an implementation for, if null the this object is its own peer/**
     * Create an instance with a peer
     *
     * @param peer      The peer BeanContext we are supplying an implementation for, if null the this object is its own peer
     */

    public BeanContextServicesSupport(BeanContextServices peer) {
        this (peer, null, false, true);
    }

    
Create an instance that is not a delegate of another object
/**
     * Create an instance that is not a delegate of another object
     */

    public BeanContextServicesSupport() {
        this (null, null, false, true);
    }

    
called by BeanContextSupport superclass during construction and
deserialization to initialize subclass transient state.
subclasses may envelope this method, but should not override it or
call it directly.
/**
     * called by BeanContextSupport superclass during construction and
     * deserialization to initialize subclass transient state.
     *
     * subclasses may envelope this method, but should not override it or
     * call it directly.
     */

    public void initialize() {
        super.initialize();

        services     = new HashMap(serializable + 1);
        bcsListeners = new ArrayList(1);
    }

    
Gets the BeanContextServices associated with this
BeanContextServicesSupport.
Returns:
the instance of BeanContext
this object is providing the implementation for./**
     * Gets the <tt>BeanContextServices</tt> associated with this
     * <tt>BeanContextServicesSupport</tt>.
     *
     * @return the instance of <tt>BeanContext</tt>
     * this object is providing the implementation for.
     */
    public BeanContextServices getBeanContextServicesPeer() {
        return (BeanContextServices)getBeanContextChildPeer();
    }

    /************************************************************************/

    /*
     * protected nested class containing per child information, an instance
     * of which is associated with each child in the "children" hashtable.
     * subclasses can extend this class to include their own per-child state.
     *
     * Note that this 'value' is serialized with the corresponding child 'key'
     * when the BeanContextSupport is serialized.
     */

    protected class BCSSChild extends BeanContextSupport.BCSChild  {

        private static final long serialVersionUID = -3263851306889194873L;

        /*
         * private nested class to map serviceClass to Provider and requestors
         * listeners.
         */

        class BCSSCServiceClassRef {

            // create an instance of a service ref

            BCSSCServiceClassRef(Class sc, BeanContextServiceProvider bcsp, boolean delegated) {
                super();

                serviceClass     = sc;

                if (delegated)
                    delegateProvider = bcsp;
                else
                    serviceProvider  = bcsp;
            }

            // add a requestor and assoc listener

            void addRequestor(Object requestor, BeanContextServiceRevokedListener bcsrl) throws TooManyListenersException {
                BeanContextServiceRevokedListener cbcsrl = (BeanContextServiceRevokedListener)requestors.get(requestor);

                if (cbcsrl != null && !cbcsrl.equals(bcsrl))
                    throw new TooManyListenersException();

                requestors.put(requestor, bcsrl);
            }

            // remove a requestor

            void removeRequestor(Object requestor) {
                requestors.remove(requestor);
            }

            // check a requestors listener

            void verifyRequestor(Object requestor, BeanContextServiceRevokedListener bcsrl) throws TooManyListenersException {
                BeanContextServiceRevokedListener cbcsrl = (BeanContextServiceRevokedListener)requestors.get(requestor);

                if (cbcsrl != null && !cbcsrl.equals(bcsrl))
                    throw new TooManyListenersException();
            }

            void verifyAndMaybeSetProvider(BeanContextServiceProvider bcsp, boolean isDelegated) {
                BeanContextServiceProvider current;

                if (isDelegated) { // the provider is delegated
                    current = delegateProvider;

                    if (current == null || bcsp == null) {
                        delegateProvider = bcsp;
                        return;
                    }
                } else { // the provider is registered with this BCS
                    current = serviceProvider;

                    if (current == null || bcsp == null) {
                        serviceProvider = bcsp;
                        return;
                    }
                }

                if (!current.equals(bcsp))
                    throw new UnsupportedOperationException("existing service reference obtained from different BeanContextServiceProvider not supported");

            }

            Iterator cloneOfEntries() {
                return ((HashMap)requestors.clone()).entrySet().iterator();
            }

            Iterator entries() { return requestors.entrySet().iterator(); }

            boolean isEmpty() { return requestors.isEmpty(); }

            Class getServiceClass() { return serviceClass; }

            BeanContextServiceProvider getServiceProvider() {
                return serviceProvider;
            }

            BeanContextServiceProvider getDelegateProvider() {
                return delegateProvider;
            }

            boolean isDelegated() { return delegateProvider != null; }

            void addRef(boolean delegated) {
                if (delegated) {
                    delegateRefs++;
                } else {
                    serviceRefs++;
                }
            }


            void releaseRef(boolean delegated) {
                if (delegated) {
                    if (--delegateRefs == 0) {
                        delegateProvider = null;
                    }
                } else {
                    if (--serviceRefs  <= 0) {
                        serviceProvider = null;
                    }
                }
            }

            int getRefs() { return serviceRefs + delegateRefs; }

            int getDelegateRefs() { return delegateRefs; }

            int getServiceRefs() { return serviceRefs; }

            /*
             * fields
             */

            Class                               serviceClass;

            BeanContextServiceProvider          serviceProvider;
            int                                 serviceRefs;

            BeanContextServiceProvider          delegateProvider; // proxy
            int                                 delegateRefs;

            HashMap                             requestors = new HashMap(1);
        }

        /*
         * per service reference info ...
         */

        class BCSSCServiceRef {
            BCSSCServiceRef(BCSSCServiceClassRef scref, boolean isDelegated) {
                serviceClassRef = scref;
                delegated       = isDelegated;
            }

            void addRef()  { refCnt++;        }
            int  release() { return --refCnt; }

            BCSSCServiceClassRef getServiceClassRef() { return serviceClassRef; }

            boolean isDelegated() { return delegated; }

            /*
             * fields
             */

            BCSSCServiceClassRef serviceClassRef;
            int                  refCnt    = 1;
            boolean              delegated = false;
        }

        BCSSChild(Object bcc, Object peer) { super(bcc, peer); }

        // note usage of service per requestor, per service

        synchronized void usingService(Object requestor, Object service, Class serviceClass, BeanContextServiceProvider bcsp, boolean isDelegated, BeanContextServiceRevokedListener bcsrl)  throws TooManyListenersException, UnsupportedOperationException {

            // first, process mapping from serviceClass to requestor(s)

            BCSSCServiceClassRef serviceClassRef = null;

            if (serviceClasses == null)
                serviceClasses = new HashMap(1);
            else
                serviceClassRef = (BCSSCServiceClassRef)serviceClasses.get(serviceClass);

            if (serviceClassRef == null) { // new service being used ...
                serviceClassRef = new BCSSCServiceClassRef(serviceClass, bcsp, isDelegated);
                serviceClasses.put(serviceClass, serviceClassRef);

            } else { // existing service ...
                serviceClassRef.verifyAndMaybeSetProvider(bcsp, isDelegated); // throws
                serviceClassRef.verifyRequestor(requestor, bcsrl); // throws
            }

            serviceClassRef.addRequestor(requestor, bcsrl);
            serviceClassRef.addRef(isDelegated);

            // now handle mapping from requestor to service(s)

            BCSSCServiceRef serviceRef = null;
            Map             services   = null;

            if (serviceRequestors == null) {
                serviceRequestors = new HashMap(1);
            } else {
                services = (Map)serviceRequestors.get(requestor);
            }

            if (services == null) {
                services = new HashMap(1);

                serviceRequestors.put(requestor, services);
            } else
                serviceRef = (BCSSCServiceRef)services.get(service);

            if (serviceRef == null) {
                serviceRef = new BCSSCServiceRef(serviceClassRef, isDelegated);

                services.put(service, serviceRef);
            } else {
                serviceRef.addRef();
            }
        }

        // release a service reference

        synchronized void releaseService(Object requestor, Object service) {
            if (serviceRequestors == null) return;

            Map services = (Map)serviceRequestors.get(requestor);

            if (services == null) return; // oops its not there anymore!

            BCSSCServiceRef serviceRef = (BCSSCServiceRef)services.get(service);

            if (serviceRef == null) return; // oops its not there anymore!

            BCSSCServiceClassRef serviceClassRef = serviceRef.getServiceClassRef();
            boolean                    isDelegated = serviceRef.isDelegated();
            BeanContextServiceProvider bcsp        = isDelegated ? serviceClassRef.getDelegateProvider() : serviceClassRef.getServiceProvider();

            bcsp.releaseService(BeanContextServicesSupport.this.getBeanContextServicesPeer(), requestor, service);

            serviceClassRef.releaseRef(isDelegated);
            serviceClassRef.removeRequestor(requestor);

            if (serviceRef.release() == 0) {

                services.remove(service);

                if (services.isEmpty()) {
                    serviceRequestors.remove(requestor);
                    serviceClassRef.removeRequestor(requestor);
                }

                if (serviceRequestors.isEmpty()) {
                    serviceRequestors = null;
                }

                if (serviceClassRef.isEmpty()) {
                    serviceClasses.remove(serviceClassRef.getServiceClass());
                }

                if (serviceClasses.isEmpty())
                    serviceClasses = null;
            }
        }

        // revoke a service

        synchronized void revokeService(Class serviceClass, boolean isDelegated, boolean revokeNow) {
            if (serviceClasses == null) return;

            BCSSCServiceClassRef serviceClassRef = (BCSSCServiceClassRef)serviceClasses.get(serviceClass);

            if (serviceClassRef == null) return;

            Iterator i = serviceClassRef.cloneOfEntries();

            BeanContextServiceRevokedEvent bcsre       = new BeanContextServiceRevokedEvent(BeanContextServicesSupport.this.getBeanContextServicesPeer(), serviceClass, revokeNow);
            boolean                        noMoreRefs  = false;

            while (i.hasNext() && serviceRequestors != null) {
                Map.Entry                         entry    = (Map.Entry)i.next();
                BeanContextServiceRevokedListener listener = (BeanContextServiceRevokedListener)entry.getValue();

                if (revokeNow) {
                    Object  requestor = entry.getKey();
                    Map     services  = (Map)serviceRequestors.get(requestor);

                    if (services != null) {
                        Iterator i1 = services.entrySet().iterator();

                        while (i1.hasNext()) {
                            Map.Entry       tmp        = (Map.Entry)i1.next();

                            BCSSCServiceRef serviceRef = (BCSSCServiceRef)tmp.getValue();
                            if (serviceRef.getServiceClassRef().equals(serviceClassRef) && isDelegated == serviceRef.isDelegated()) {
                                i1.remove();
                            }
                        }

                        if (noMoreRefs = services.isEmpty()) {
                            serviceRequestors.remove(requestor);
                        }
                    }

                    if (noMoreRefs) serviceClassRef.removeRequestor(requestor);
                }

                listener.serviceRevoked(bcsre);
            }

            if (revokeNow && serviceClasses != null) {
                if (serviceClassRef.isEmpty())
                    serviceClasses.remove(serviceClass);

                if (serviceClasses.isEmpty())
                    serviceClasses = null;
            }

            if (serviceRequestors != null && serviceRequestors.isEmpty())
                serviceRequestors = null;
        }

        // release all references for this child since it has been unnested.

        void cleanupReferences() {

            if (serviceRequestors == null) return;

            Iterator requestors = serviceRequestors.entrySet().iterator();

            while(requestors.hasNext()) {
                Map.Entry            tmp       = (Map.Entry)requestors.next();
                Object               requestor = tmp.getKey();
                Iterator             services  = ((Map)tmp.getValue()).entrySet().iterator();

                requestors.remove();

                while (services.hasNext()) {
                    Map.Entry       entry   = (Map.Entry)services.next();
                    Object          service = entry.getKey();
                    BCSSCServiceRef sref    = (BCSSCServiceRef)entry.getValue();

                    BCSSCServiceClassRef       scref = sref.getServiceClassRef();

                    BeanContextServiceProvider bcsp  = sref.isDelegated() ? scref.getDelegateProvider() : scref.getServiceProvider();

                    scref.removeRequestor(requestor);
                    services.remove();

                    while (sref.release() >= 0) {
                        bcsp.releaseService(BeanContextServicesSupport.this.getBeanContextServicesPeer(), requestor, service);
                    }
                }
            }

            serviceRequestors = null;
            serviceClasses    = null;
        }

        void revokeAllDelegatedServicesNow() {
            if (serviceClasses == null) return;

            Iterator serviceClassRefs  =
                new HashSet(serviceClasses.values()).iterator();

            while (serviceClassRefs.hasNext()) {
                BCSSCServiceClassRef serviceClassRef = (BCSSCServiceClassRef)serviceClassRefs.next();

                if (!serviceClassRef.isDelegated()) continue;

                Iterator i = serviceClassRef.cloneOfEntries();
                BeanContextServiceRevokedEvent bcsre       = new BeanContextServiceRevokedEvent(BeanContextServicesSupport.this.getBeanContextServicesPeer(), serviceClassRef.getServiceClass(), true);
                boolean                        noMoreRefs  = false;

                while (i.hasNext()) {
                    Map.Entry                         entry     = (Map.Entry)i.next();
                    BeanContextServiceRevokedListener listener  = (BeanContextServiceRevokedListener)entry.getValue();

                    Object                            requestor = entry.getKey();
                    Map                               services  = (Map)serviceRequestors.get(requestor);

                    if (services != null) {
                        Iterator i1 = services.entrySet().iterator();

                        while (i1.hasNext()) {
                            Map.Entry       tmp        = (Map.Entry)i1.next();

                            BCSSCServiceRef serviceRef = (BCSSCServiceRef)tmp.getValue();
                            if (serviceRef.getServiceClassRef().equals(serviceClassRef) && serviceRef.isDelegated()) {
                                i1.remove();
                            }
                        }

                        if (noMoreRefs = services.isEmpty()) {
                            serviceRequestors.remove(requestor);
                        }
                    }

                    if (noMoreRefs) serviceClassRef.removeRequestor(requestor);

                    listener.serviceRevoked(bcsre);

                    if (serviceClassRef.isEmpty())
                        serviceClasses.remove(serviceClassRef.getServiceClass());
                }
            }

            if (serviceClasses.isEmpty()) serviceClasses = null;

            if (serviceRequestors != null && serviceRequestors.isEmpty())
                serviceRequestors = null;
        }

        /*
         * fields
         */

        private transient HashMap       serviceClasses;
        private transient HashMap       serviceRequestors;
    }

    

Subclasses can override this method to insert their own subclass
of Child without having to override add() or the other Collection
methods that add children to the set.

Params:
targetChild – the child to create the Child on behalf of
peer –        the peer if the targetChild and peer are related by BeanContextProxy/**
     * <p>
     * Subclasses can override this method to insert their own subclass
     * of Child without having to override add() or the other Collection
     * methods that add children to the set.
     * </p>
     *
     * @param targetChild the child to create the Child on behalf of
     * @param peer        the peer if the targetChild and peer are related by BeanContextProxy
     */

    protected BCSChild createBCSChild(Object targetChild, Object peer) {
        return new BCSSChild(targetChild, peer);
    }

    /************************************************************************/

        
subclasses may subclass this nested class to add behaviors for
each BeanContextServicesProvider.
/**
         * subclasses may subclass this nested class to add behaviors for
         * each BeanContextServicesProvider.
         */

        protected static class BCSSServiceProvider implements Serializable {
            private static final long serialVersionUID = 861278251667444782L;

            BCSSServiceProvider(Class sc, BeanContextServiceProvider bcsp) {
                super();

                serviceProvider = bcsp;
            }

            
Returns the service provider.
Returns:
the service provider/**
             * Returns the service provider.
             * @return the service provider
             */
            protected BeanContextServiceProvider getServiceProvider() {
                return serviceProvider;
            }

            
The service provider.
/**
             * The service provider.
             */

            protected BeanContextServiceProvider serviceProvider;
        }

        
subclasses can override this method to create new subclasses of
BCSSServiceProvider without having to override addService() in
order to instantiate.
Params:
sc – the class
bcsp – the service provider
Returns:
a service provider without overriding addService()/**
         * subclasses can override this method to create new subclasses of
         * BCSSServiceProvider without having to override addService() in
         * order to instantiate.
         * @param sc the class
         * @param bcsp the service provider
         * @return a service provider without overriding addService()
         */

        protected BCSSServiceProvider createBCSSServiceProvider(Class sc, BeanContextServiceProvider bcsp) {
            return new BCSSServiceProvider(sc, bcsp);
        }

    /************************************************************************/

    
add a BeanContextServicesListener
Throws:
NullPointerException – if the argument is null/**
     * add a BeanContextServicesListener
     *
     * @throws NullPointerException if the argument is null
     */

    public void addBeanContextServicesListener(BeanContextServicesListener bcsl) {
        if (bcsl == null) throw new NullPointerException("bcsl");

        synchronized(bcsListeners) {
            if (bcsListeners.contains(bcsl))
                return;
            else
                bcsListeners.add(bcsl);
        }
    }

    
remove a BeanContextServicesListener
/**
     * remove a BeanContextServicesListener
     */

    public void removeBeanContextServicesListener(BeanContextServicesListener bcsl) {
        if (bcsl == null) throw new NullPointerException("bcsl");

        synchronized(bcsListeners) {
            if (!bcsListeners.contains(bcsl))
                return;
            else
                bcsListeners.remove(bcsl);
        }
    }

    
add a service
Params:
serviceClass – the service class
bcsp – the service provider/**
     * add a service
     * @param serviceClass the service class
     * @param bcsp the service provider
     */

    public boolean addService(Class serviceClass, BeanContextServiceProvider bcsp) {
        return addService(serviceClass, bcsp, true);
    }

    
add a service
Params:
serviceClass – the service class
bcsp – the service provider
fireEvent – whether or not an event should be fired
Returns:
true if the service was successfully added/**
     * add a service
     * @param serviceClass the service class
     * @param bcsp the service provider
     * @param fireEvent whether or not an event should be fired
     * @return true if the service was successfully added
     */

    protected boolean addService(Class serviceClass, BeanContextServiceProvider bcsp, boolean fireEvent) {

        if (serviceClass == null) throw new NullPointerException("serviceClass");
        if (bcsp         == null) throw new NullPointerException("bcsp");

        synchronized(BeanContext.globalHierarchyLock) {
            if (services.containsKey(serviceClass))
                return false;
            else {
                services.put(serviceClass,  createBCSSServiceProvider(serviceClass, bcsp));

                if (bcsp instanceof Serializable) serializable++;

                if (!fireEvent) return true;


                BeanContextServiceAvailableEvent bcssae = new BeanContextServiceAvailableEvent(getBeanContextServicesPeer(), serviceClass);

                fireServiceAdded(bcssae);

                synchronized(children) {
                    Iterator i = children.keySet().iterator();

                    while (i.hasNext()) {
                        Object c = i.next();

                        if (c instanceof BeanContextServices) {
                            ((BeanContextServicesListener)c).serviceAvailable(bcssae);
                        }
                    }
                }

                return true;
            }
        }
    }

    
remove a service
Params:
serviceClass – the service class
bcsp – the service provider
revokeCurrentServicesNow – whether or not to revoke the service/**
     * remove a service
     * @param serviceClass the service class
     * @param bcsp the service provider
     * @param revokeCurrentServicesNow whether or not to revoke the service
     */

    public void revokeService(Class serviceClass, BeanContextServiceProvider bcsp, boolean revokeCurrentServicesNow) {

        if (serviceClass == null) throw new NullPointerException("serviceClass");
        if (bcsp         == null) throw new NullPointerException("bcsp");

        synchronized(BeanContext.globalHierarchyLock) {
            if (!services.containsKey(serviceClass)) return;

            BCSSServiceProvider bcsssp = (BCSSServiceProvider)services.get(serviceClass);

            if (!bcsssp.getServiceProvider().equals(bcsp))
                throw new IllegalArgumentException("service provider mismatch");

            services.remove(serviceClass);

            if (bcsp instanceof Serializable) serializable--;

            Iterator i = bcsChildren(); // get the BCSChild values.

            while (i.hasNext()) {
                ((BCSSChild)i.next()).revokeService(serviceClass, false, revokeCurrentServicesNow);
            }

            fireServiceRevoked(serviceClass, revokeCurrentServicesNow);
        }
    }

    
has a service, which may be delegated
/**
     * has a service, which may be delegated
     */

    public synchronized boolean hasService(Class serviceClass) {
        if (serviceClass == null) throw new NullPointerException("serviceClass");

        synchronized(BeanContext.globalHierarchyLock) {
            if (services.containsKey(serviceClass)) return true;

            BeanContextServices bcs = null;

            try {
                bcs = (BeanContextServices)getBeanContext();
            } catch (ClassCastException cce) {
                return false;
            }

            return bcs == null ? false : bcs.hasService(serviceClass);
        }
    }

    /************************************************************************/

    /*
     * a nested subclass used to represent a proxy for serviceClasses delegated
     * to an enclosing BeanContext.
     */

    protected class BCSSProxyServiceProvider implements BeanContextServiceProvider, BeanContextServiceRevokedListener {

        BCSSProxyServiceProvider(BeanContextServices bcs) {
            super();

            nestingCtxt = bcs;
        }

        public Object getService(BeanContextServices bcs, Object requestor, Class serviceClass, Object serviceSelector) {
            Object service = null;

            try {
                service = nestingCtxt.getService(bcs, requestor, serviceClass, serviceSelector, this);
            } catch (TooManyListenersException tmle) {
                return null;
            }

            return service;
        }

        public void releaseService(BeanContextServices bcs, Object requestor, Object service) {
            nestingCtxt.releaseService(bcs, requestor, service);
        }

        public Iterator getCurrentServiceSelectors(BeanContextServices bcs, Class serviceClass) {
            return nestingCtxt.getCurrentServiceSelectors(serviceClass);
        }

        public void serviceRevoked(BeanContextServiceRevokedEvent bcsre) {
            Iterator i = bcsChildren(); // get the BCSChild values.

            while (i.hasNext()) {
                ((BCSSChild)i.next()).revokeService(bcsre.getServiceClass(), true, bcsre.isCurrentServiceInvalidNow());
            }
        }

        /*
         * fields
         */

        private BeanContextServices nestingCtxt;
    }

    /************************************************************************/

    
obtain a service which may be delegated
/**
     * obtain a service which may be delegated
     */

     public Object getService(BeanContextChild child, Object requestor, Class serviceClass, Object serviceSelector, BeanContextServiceRevokedListener bcsrl) throws TooManyListenersException {
        if (child        == null) throw new NullPointerException("child");
        if (serviceClass == null) throw new NullPointerException("serviceClass");
        if (requestor    == null) throw new NullPointerException("requestor");
        if (bcsrl        == null) throw new NullPointerException("bcsrl");

        Object              service = null;
        BCSSChild           bcsc;
        BeanContextServices bcssp   = getBeanContextServicesPeer();

        synchronized(BeanContext.globalHierarchyLock) {
            synchronized(children) { bcsc = (BCSSChild)children.get(child); }

            if (bcsc == null) throw new IllegalArgumentException("not a child of this context"); // not a child ...

            BCSSServiceProvider bcsssp = (BCSSServiceProvider)services.get(serviceClass);

            if (bcsssp != null) {
                BeanContextServiceProvider bcsp = bcsssp.getServiceProvider();
                service = bcsp.getService(bcssp, requestor, serviceClass, serviceSelector);
                if (service != null) { // do bookkeeping ...
                    try {
                        bcsc.usingService(requestor, service, serviceClass, bcsp, false, bcsrl);
                    } catch (TooManyListenersException tmle) {
                        bcsp.releaseService(bcssp, requestor, service);
                        throw tmle;
                    } catch (UnsupportedOperationException uope) {
                        bcsp.releaseService(bcssp, requestor, service);
                        throw uope; // unchecked rt exception
                    }

                    return service;
                }
            }


            if (proxy != null) {

                // try to delegate ...

                service = proxy.getService(bcssp, requestor, serviceClass, serviceSelector);

                if (service != null) { // do bookkeeping ...
                    try {
                        bcsc.usingService(requestor, service, serviceClass, proxy, true, bcsrl);
                    } catch (TooManyListenersException tmle) {
                        proxy.releaseService(bcssp, requestor, service);
                        throw tmle;
                    } catch (UnsupportedOperationException uope) {
                        proxy.releaseService(bcssp, requestor, service);
                        throw uope; // unchecked rt exception
                    }

                    return service;
                }
            }
        }

        return null;
    }

    
release a service
/**
     * release a service
     */

    public void releaseService(BeanContextChild child, Object requestor, Object service) {
        if (child     == null) throw new NullPointerException("child");
        if (requestor == null) throw new NullPointerException("requestor");
        if (service   == null) throw new NullPointerException("service");

        BCSSChild bcsc;

        synchronized(BeanContext.globalHierarchyLock) {
                synchronized(children) { bcsc = (BCSSChild)children.get(child); }

                if (bcsc != null)
                    bcsc.releaseService(requestor, service);
                else
                   throw new IllegalArgumentException("child actual is not a child of this BeanContext");
        }
    }

    
Returns:
an iterator for all the currently registered service classes./**
     * @return an iterator for all the currently registered service classes.
     */

    public Iterator getCurrentServiceClasses() {
        return new BCSIterator(services.keySet().iterator());
    }

    
Returns:
an iterator for all the currently available service selectors
(if any) available for the specified service./**
     * @return an iterator for all the currently available service selectors
     * (if any) available for the specified service.
     */

    public Iterator getCurrentServiceSelectors(Class serviceClass) {

        BCSSServiceProvider bcsssp = (BCSSServiceProvider)services.get(serviceClass);

        return bcsssp != null ? new BCSIterator(bcsssp.getServiceProvider().getCurrentServiceSelectors(getBeanContextServicesPeer(), serviceClass)) : null;
    }

    
BeanContextServicesListener callback, propagates event to all
currently registered listeners and BeanContextServices children,
if this BeanContextService does not already implement this service
itself.
subclasses may override or envelope this method to implement their
own propagation semantics.
/**
     * BeanContextServicesListener callback, propagates event to all
     * currently registered listeners and BeanContextServices children,
     * if this BeanContextService does not already implement this service
     * itself.
     *
     * subclasses may override or envelope this method to implement their
     * own propagation semantics.
     */

     public void serviceAvailable(BeanContextServiceAvailableEvent bcssae) {
        synchronized(BeanContext.globalHierarchyLock) {
            if (services.containsKey(bcssae.getServiceClass())) return;

            fireServiceAdded(bcssae);

            Iterator i;

            synchronized(children) {
                i = children.keySet().iterator();
            }

            while (i.hasNext()) {
                Object c = i.next();

                if (c instanceof BeanContextServices) {
                    ((BeanContextServicesListener)c).serviceAvailable(bcssae);
                }
            }
        }
     }

    
BeanContextServicesListener callback, propagates event to all
currently registered listeners and BeanContextServices children,
if this BeanContextService does not already implement this service
itself.
subclasses may override or envelope this method to implement their
own propagation semantics.
/**
     * BeanContextServicesListener callback, propagates event to all
     * currently registered listeners and BeanContextServices children,
     * if this BeanContextService does not already implement this service
     * itself.
     *
     * subclasses may override or envelope this method to implement their
     * own propagation semantics.
     */

    public void serviceRevoked(BeanContextServiceRevokedEvent bcssre) {
        synchronized(BeanContext.globalHierarchyLock) {
            if (services.containsKey(bcssre.getServiceClass())) return;

            fireServiceRevoked(bcssre);

            Iterator i;

            synchronized(children) {
                i = children.keySet().iterator();
            }

            while (i.hasNext()) {
                Object c = i.next();

                if (c instanceof BeanContextServices) {
                    ((BeanContextServicesListener)c).serviceRevoked(bcssre);
                }
            }
        }
    }

    
Gets the BeanContextServicesListener (if any) of the specified
child.
Params:
child – the specified child
Returns:
the BeanContextServicesListener (if any) of the specified child/**
     * Gets the <tt>BeanContextServicesListener</tt> (if any) of the specified
     * child.
     *
     * @param child the specified child
     * @return the BeanContextServicesListener (if any) of the specified child
     */
    protected static final BeanContextServicesListener getChildBeanContextServicesListener(Object child) {
        try {
            return (BeanContextServicesListener)child;
        } catch (ClassCastException cce) {
            return null;
        }
    }

    
called from superclass child removal operations after a child
has been successfully removed. called with child synchronized.
This subclass uses this hook to immediately revoke any services
being used by this child if it is a BeanContextChild.
subclasses may envelope this method in order to implement their
own child removal side-effects.
/**
     * called from superclass child removal operations after a child
     * has been successfully removed. called with child synchronized.
     *
     * This subclass uses this hook to immediately revoke any services
     * being used by this child if it is a BeanContextChild.
     *
     * subclasses may envelope this method in order to implement their
     * own child removal side-effects.
     */

    protected void childJustRemovedHook(Object child, BCSChild bcsc) {
        BCSSChild bcssc = (BCSSChild)bcsc;

        bcssc.cleanupReferences();
    }

    
called from setBeanContext to notify a BeanContextChild
to release resources obtained from the nesting BeanContext.
This method revokes any services obtained from its parent.
subclasses may envelope this method to implement their own semantics.
/**
     * called from setBeanContext to notify a BeanContextChild
     * to release resources obtained from the nesting BeanContext.
     *
     * This method revokes any services obtained from its parent.
     *
     * subclasses may envelope this method to implement their own semantics.
     */

    protected synchronized void releaseBeanContextResources() {
        Object[] bcssc;

        super.releaseBeanContextResources();

        synchronized(children) {
            if (children.isEmpty()) return;

            bcssc = children.values().toArray();
        }


        for (int i = 0; i < bcssc.length; i++) {
            ((BCSSChild)bcssc[i]).revokeAllDelegatedServicesNow();
        }

        proxy = null;
    }

    
called from setBeanContext to notify a BeanContextChild
to allocate resources obtained from the nesting BeanContext.
subclasses may envelope this method to implement their own semantics.
/**
     * called from setBeanContext to notify a BeanContextChild
     * to allocate resources obtained from the nesting BeanContext.
     *
     * subclasses may envelope this method to implement their own semantics.
     */

    protected synchronized void initializeBeanContextResources() {
        super.initializeBeanContextResources();

        BeanContext nbc = getBeanContext();

        if (nbc == null) return;

        try {
            BeanContextServices bcs = (BeanContextServices)nbc;

            proxy = new BCSSProxyServiceProvider(bcs);
        } catch (ClassCastException cce) {
            // do nothing ...
        }
    }

    
Fires a BeanContextServiceEvent notifying of a new service.
Params:
serviceClass – the service class/**
     * Fires a <tt>BeanContextServiceEvent</tt> notifying of a new service.
     * @param serviceClass the service class
     */
    protected final void fireServiceAdded(Class serviceClass) {
        BeanContextServiceAvailableEvent bcssae = new BeanContextServiceAvailableEvent(getBeanContextServicesPeer(), serviceClass);

        fireServiceAdded(bcssae);
    }

    
Fires a BeanContextServiceAvailableEvent indicating that a new
service has become available.
Params:
bcssae – the BeanContextServiceAvailableEvent/**
     * Fires a <tt>BeanContextServiceAvailableEvent</tt> indicating that a new
     * service has become available.
     *
     * @param bcssae the <tt>BeanContextServiceAvailableEvent</tt>
     */
    protected final void fireServiceAdded(BeanContextServiceAvailableEvent bcssae) {
        Object[]                         copy;

        synchronized (bcsListeners) { copy = bcsListeners.toArray(); }

        for (int i = 0; i < copy.length; i++) {
            ((BeanContextServicesListener)copy[i]).serviceAvailable(bcssae);
        }
    }

    
Fires a BeanContextServiceEvent notifying of a service being revoked.
Params:
bcsre – the BeanContextServiceRevokedEvent/**
     * Fires a <tt>BeanContextServiceEvent</tt> notifying of a service being revoked.
     *
     * @param bcsre the <tt>BeanContextServiceRevokedEvent</tt>
     */
    protected final void fireServiceRevoked(BeanContextServiceRevokedEvent bcsre) {
        Object[]                         copy;

        synchronized (bcsListeners) { copy = bcsListeners.toArray(); }

        for (int i = 0; i < copy.length; i++) {
            ((BeanContextServiceRevokedListener)copy[i]).serviceRevoked(bcsre);
        }
    }

    
Fires a BeanContextServiceRevokedEvent
indicating that a particular service is
no longer available.
Params:
serviceClass – the service class
revokeNow – whether or not the event should be revoked now/**
     * Fires a <tt>BeanContextServiceRevokedEvent</tt>
     * indicating that a particular service is
     * no longer available.
     * @param serviceClass the service class
     * @param revokeNow whether or not the event should be revoked now
     */
    protected final void fireServiceRevoked(Class serviceClass, boolean revokeNow) {
        Object[]                       copy;
        BeanContextServiceRevokedEvent bcsre = new BeanContextServiceRevokedEvent(getBeanContextServicesPeer(), serviceClass, revokeNow);

        synchronized (bcsListeners) { copy = bcsListeners.toArray(); }

        for (int i = 0; i < copy.length; i++) {
            ((BeanContextServicesListener)copy[i]).serviceRevoked(bcsre);
        }
   }

    
called from BeanContextSupport writeObject before it serializes the
children ...
This class will serialize any Serializable BeanContextServiceProviders
herein.
subclasses may envelope this method to insert their own serialization
processing that has to occur prior to serialization of the children
/**
     * called from BeanContextSupport writeObject before it serializes the
     * children ...
     *
     * This class will serialize any Serializable BeanContextServiceProviders
     * herein.
     *
     * subclasses may envelope this method to insert their own serialization
     * processing that has to occur prior to serialization of the children
     */

    protected synchronized void bcsPreSerializationHook(ObjectOutputStream oos) throws IOException {

        oos.writeInt(serializable);

        if (serializable <= 0) return;

        int count = 0;

        Iterator i = services.entrySet().iterator();

        while (i.hasNext() && count < serializable) {
            Map.Entry           entry = (Map.Entry)i.next();
            BCSSServiceProvider bcsp  = null;

             try {
                bcsp = (BCSSServiceProvider)entry.getValue();
             } catch (ClassCastException cce) {
                continue;
             }

             if (bcsp.getServiceProvider() instanceof Serializable) {
                oos.writeObject(entry.getKey());
                oos.writeObject(bcsp);
                count++;
             }
        }

        if (count != serializable)
            throw new IOException("wrote different number of service providers than expected");
    }

    
called from BeanContextSupport readObject before it deserializes the
children ...
This class will deserialize any Serializable BeanContextServiceProviders
serialized earlier thus making them available to the children when they
deserialized.
subclasses may envelope this method to insert their own serialization
processing that has to occur prior to serialization of the children
/**
     * called from BeanContextSupport readObject before it deserializes the
     * children ...
     *
     * This class will deserialize any Serializable BeanContextServiceProviders
     * serialized earlier thus making them available to the children when they
     * deserialized.
     *
     * subclasses may envelope this method to insert their own serialization
     * processing that has to occur prior to serialization of the children
     */

    protected synchronized void bcsPreDeserializationHook(ObjectInputStream ois) throws IOException, ClassNotFoundException {

        serializable = ois.readInt();

        int count = serializable;

        while (count > 0) {
            services.put(ois.readObject(), ois.readObject());
            count--;
        }
    }

    
serialize the instance
/**
     * serialize the instance
     */

    private synchronized void writeObject(ObjectOutputStream oos) throws IOException {
        oos.defaultWriteObject();

        serialize(oos, (Collection)bcsListeners);
    }

    
deserialize the instance
/**
     * deserialize the instance
     */

    private synchronized void readObject(ObjectInputStream ois) throws IOException, ClassNotFoundException {

        ois.defaultReadObject();

        deserialize(ois, (Collection)bcsListeners);
    }


    /*
     * fields
     */

    
all accesses to the  protected transient HashMap services 
field should be synchronized on that object
/**
     * all accesses to the <code> protected transient HashMap services </code>
     * field should be synchronized on that object
     */
    protected transient HashMap                  services;

    
The number of instances of a serializable BeanContextServceProvider.
/**
     * The number of instances of a serializable <tt>BeanContextServceProvider</tt>.
     */
    protected transient int                      serializable = 0;


    
Delegate for the BeanContextServiceProvider.
/**
     * Delegate for the <tt>BeanContextServiceProvider</tt>.
     */
    protected transient BCSSProxyServiceProvider proxy;


    
List of BeanContextServicesListener objects.
/**
     * List of <tt>BeanContextServicesListener</tt> objects.
     */
    protected transient ArrayList                bcsListeners;
}