001    /* DGC.java --
002       Copyright (c) 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    package java.rmi.dgc;
039    
040    import java.rmi.Remote;
041    import java.rmi.RemoteException;
042    import java.rmi.server.ObjID;
043    
044    /**
045     * The DGC implementation is used for the server side during the distributed
046     * garbage collection. This interface contains the two methods: dirty and clean.
047     * A dirty call is made when a remote reference is unmarshaled in a client. A
048     * corresponding clean call is made by client it no longer uses that remote
049     * reference. A reference to a remote object is also automatically released
050     * after so called lease period that starts after the dirty call is received. It
051     * is the client's responsibility to renew the leases, by making additional
052     * dirty calls before such leases expire.
053     */
054    public interface DGC
055        extends Remote
056    {
057      /**
058       * Mark the given objects referecnes as used on the client side.
059       *
060       * @param ids the ids of the used objects.
061       * @param sequenceNum the number of the call (used to detect and discard late
062       *          calls).
063       * @param lease the requested lease
064       * @return the granted lease
065       */
066      Lease dirty(ObjID[] ids, long sequenceNum, Lease lease)
067          throws RemoteException;
068    
069      /**
070       * Mark the given objects as no longer used on the client side.
071       *
072       * @param ids the ids of the objects that are no longer used.
073       * @param sequenceNum the number of the call (used to detect and discard late
074       * @param vmid the VMID of the client.
075       * @param strong make the "strong" clean call ("strong" calls are scheduled
076       * after the failed dirty calls).
077       */
078      void clean(ObjID[] ids, long sequenceNum, VMID vmid, boolean strong)
079          throws RemoteException;
080    }