Java example source code file (BeanContextServicesSupport.java)
The BeanContextServicesSupport.java Java example source code/*
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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,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 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;
/**
* <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;
/**
* <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.
*
* @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
*
* @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
*
* @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
*/
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.
*/
public void initialize() {
super.initialize();
services = new HashMap(serializable + 1);
bcsListeners = new ArrayList(1);
}
/**
* Gets the <tt>BeanContextServices associated with this
* <tt>BeanContextServicesSupport.
*
* @return the instance of <tt>BeanContext
* 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;
}
/**
* <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.
*/
protected static class BCSSServiceProvider implements Serializable {
private static final long serialVersionUID = 861278251667444782L;
BCSSServiceProvider(Class sc, BeanContextServiceProvider bcsp) {
super();
serviceProvider = bcsp;
}
/**
* Returns the service provider.
* @return the service provider
*/
protected BeanContextServiceProvider getServiceProvider() {
return serviceProvider;
}
/**
* 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.
* @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
*/
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
*/
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
* @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
* @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
* @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
*/
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
*/
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
*/
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");
}
}
/**
* @return an iterator for all the currently registered service classes.
*/
public Iterator getCurrentServiceClasses() {
return new BCSIterator(services.keySet().iterator());
}
/**
* @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.
*/
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.
*/
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 <tt>BeanContextServicesListener (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.
*/
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.
*/
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.
*/
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 <tt>BeanContextServiceEvent 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 <tt>BeanContextServiceAvailableEvent indicating that a new
* service has become available.
*
* @param bcssae the <tt>BeanContextServiceAvailableEvent
*/
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 <tt>BeanContextServiceEvent notifying of a service being revoked.
*
* @param bcsre the <tt>BeanContextServiceRevokedEvent
*/
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 <tt>BeanContextServiceRevokedEvent
* 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
*/
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
*/
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
*/
private synchronized void writeObject(ObjectOutputStream oos) throws IOException {
oos.defaultWriteObject();
serialize(oos, (Collection)bcsListeners);
}
/**
* deserialize the instance
*/
private synchronized void readObject(ObjectInputStream ois) throws IOException, ClassNotFoundException {
ois.defaultReadObject();
deserialize(ois, (Collection)bcsListeners);
}
/*
* fields
*/
/**
* all accesses to the <code> protected transient HashMap services
* field should be synchronized on that object
*/
protected transient HashMap services;
/**
* The number of instances of a serializable <tt>BeanContextServceProvider.
*/
protected transient int serializable = 0;
/**
* Delegate for the <tt>BeanContextServiceProvider.
*/
protected transient BCSSProxyServiceProvider proxy;
/**
* List of <tt>BeanContextServicesListener objects.
*/
protected transient ArrayList bcsListeners;
}
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