| /* java.beans.beancontext.BeanContextServiceProvider |
| Copyright (C) 1999 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package java.beans.beancontext; |
| |
| import java.util.Iterator; |
| |
| /** |
| * An actual factory for services. |
| * <P> |
| * |
| * It is the <code>BeanContextServiceProvider</code>'s responsibility to |
| * register itself with whatever <code>BeanContextServices</code> object |
| * it wishes to provide services through using the |
| * <code>addService()</code> method. |
| * <P> |
| * |
| * If for some reason it can no longer provide services for a particular |
| * class, this class must invoke |
| * <code>BeanContextServices.revokeService(serviceClass,this,true)</code> |
| * for all the places it has registered the service. |
| * |
| * @author John Keiser |
| * @since JDK1.2 |
| */ |
| |
| public interface BeanContextServiceProvider { |
| /** |
| * Get a service. |
| * Called from <code>BeanContextServices.getService()</code>. |
| * |
| * <p>If the requested service class is not available, or if this |
| * <code>BeanContextServiceProvider</code> chooses not honor the |
| * request for some reason, then this method will return |
| * <code>null</code>.</p> |
| * |
| * This method may throw unchecked exceptions, so watch out. |
| * |
| * @param services the <code>BeanContextServices</code> that wants |
| * to get the service. Only weak references to this will |
| * be retained, and it will never be changed, only queried |
| * in a read-only manner. |
| * @param requestor the actual requestor of the service. Only |
| * weak references to this will be retained, and it will |
| * never be changed, only queried in a read-only manner. |
| * @param serviceClass the <code>Class</code> of the service being |
| * requested. |
| * @param serviceSelector a parameter to customize the service |
| * returned with. |
| * @return an instance of <code>serviceClass</code> (such that |
| * <code>instanceof</code> serviceClass is true), or |
| * <code>null</code>. |
| * @see java.beans.beancontext.BeanContextServices#getService(java.beans.beancontext.BeanContextChild,java.lang.Object,java.lang.Class,java.lang.Object,java.beans.beancontext.BeanContextServiceRevokedListener) |
| */ |
| Object getService(BeanContextServices services, Object requestor, Class serviceClass, Object serviceSelector); |
| |
| /** |
| * Release the service. |
| * <P> |
| * |
| * Called by <code>BeanContextServices.releaseService()</code>. |
| * <P> |
| * |
| * Most <code>BeanContextServiceProvider</code>s won't have to do |
| * anything here. |
| * |
| * @param services the <code>BeanContextServices</code> that wants |
| * to release the service. Only weak references to this will |
| * be retained, and it will never be changed, only queried |
| * in a read-only manner. |
| * @param requestor the original requestor of the service. |
| * @param service the service to relinquish |
| * @see java.beans.beancontext.BeanContextServices#releaseService(java.beans.beancontext.BeanContextChild,java.lang.Object,java.lang.Object) |
| */ |
| void releaseService(BeanContextServices services, Object requestor, Object service); |
| |
| /** |
| * Get a list of valid service selectors for the specified service class. |
| * This method is called from |
| * <code>BeanContextServices.getCurrentServiceSelectors()</code>. |
| * <P> |
| * |
| * If the specified service class does not have a finite number of |
| * valid service selectors, it should return <code>null</code>. |
| * If it takes a general <code>Integer</code> parameter, for |
| * example, you may as well return <code>null</code> or the poor |
| * soul who called this method will be iterating all day. |
| * <P> |
| * |
| * If it has no valid service selectors, it should still return an empty |
| * <code>Iterator</code>. |
| * |
| * @param services the <code>BeanContextServices</code> that wants |
| * to get the service selectors. Only weak references to this will |
| * be retained, and it will never be changed, only queried |
| * in a read-only manner. |
| * @param serviceClass the service class to get selectors for. |
| * @return a list of valid service selectors for the service |
| * class, or <code>null</code>. |
| * @see java.beans.beancontext.BeanContextServices#getCurrentServiceSelectors(java.lang.Class) |
| */ |
| Iterator getCurrentServiceSelectors(BeanContextServices services, Class serviceClass); |
| } |