/* DGC.java --
   Copyright (c) 1996, 1997, 1998, 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
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02110-1301 USA.

Linking this library statically or dynamically with other modules is
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permission to link this library with independent modules to produce an
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package java.rmi.dgc;

import java.rmi.Remote;
import java.rmi.RemoteException;
import java.rmi.server.ObjID;

/**
 * The DGC implementation is used for the server side during the distributed
 * garbage collection. This interface contains the two methods: dirty and clean.
 * A dirty call is made when a remote reference is unmarshaled in a client. A
 * corresponding clean call is made by client it no longer uses that remote
 * reference. A reference to a remote object is also automatically released
 * after so called lease period that starts after the dirty call is received. It
 * is the client's responsibility to renew the leases, by making additional
 * dirty calls before such leases expire.
 */
public interface DGC
    extends Remote
{
  /**
   * Mark the given objects referecnes as used on the client side.
   *
   * @param ids the ids of the used objects.
   * @param sequenceNum the number of the call (used to detect and discard late
   *          calls).
   * @param lease the requested lease
   * @return the granted lease
   */
  Lease dirty(ObjID[] ids, long sequenceNum, Lease lease)
      throws RemoteException;

  /**
   * Mark the given objects as no longer used on the client side.
   *
   * @param ids the ids of the objects that are no longer used.
   * @param sequenceNum the number of the call (used to detect and discard late
   * @param vmid the VMID of the client.
   * @param strong make the "strong" clean call ("strong" calls are scheduled
   * after the failed dirty calls).
   */
  void clean(ObjID[] ids, long sequenceNum, VMID vmid, boolean strong)
      throws RemoteException;
}