Imported GNU Classpath 0.90

       * scripts/makemake.tcl: Set gnu/java/awt/peer/swing to ignore.
       * gnu/classpath/jdwp/VMFrame.java (SIZE): New constant.
       * java/lang/VMCompiler.java: Use gnu.java.security.hash.MD5.
       * java/lang/Math.java: New override file.
       * java/lang/Character.java: Merged from Classpath.
       (start, end): Now 'int's.
       (canonicalName): New field.
       (CANONICAL_NAME, NO_SPACES_NAME, CONSTANT_NAME): New constants.
       (UnicodeBlock): Added argument.
       (of): New overload.
       (forName): New method.
       Updated unicode blocks.
       (sets): Updated.
       * sources.am: Regenerated.
       * Makefile.in: Likewise.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@111942 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 127 insertions, 51 deletions

diff --git a/libjava/classpath/gnu/java/rmi/dgc/DGCImpl.java b/libjava/classpath/gnu/java/rmi/dgc/DGCImpl.java
index a32445c343b..a7bc0940ed0 100644
--- a/libjava/classpath/gnu/java/rmi/dgc/DGCImpl.java
+++ b/libjava/classpath/gnu/java/rmi/dgc/DGCImpl.java
@@ -8,7 +8,7 @@ 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
@@ -49,70 +49,146 @@ import java.rmi.server.RMISocketFactory;
 import java.util.Hashtable;
 
 /**
-  * I let DGCImpl to extend UnicastServerRef, but not 
-  * UnicastRemoteObject, because UnicastRemoteObject must
-  * exportObject automatically.
-  */
+ * 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 class DGCImpl
-    extends UnicastServerRef implements DGC {
-
-    private static final long LEASE_VALUE = 600000L;
-    // leaseCache caches a LeaseRecord associated with a vmid
-    private Hashtable leaseCache = new Hashtable();
-
-public DGCImpl() throws RemoteException {
-    	super(new ObjID(ObjID.DGC_ID), 0, RMISocketFactory.getSocketFactory());
-}
-
-public Lease dirty(ObjID[] ids, long sequenceNum, Lease lease) throws RemoteException {
-	VMID vmid = lease.getVMID();
-    	if (vmid == null)
-    	    vmid = new VMID();
-    	long leaseValue = LEASE_VALUE;
-    	//long leaseValue = lease.getValue();
+    extends UnicastServerRef
+    implements DGC
+{
+  /*
+   * The DGCImpl extends UnicastServerRef and not UnicastRemoteObject, because
+   * UnicastRemoteObject must exportObject automatically.
+   */
+  
+  /**
+   * This defauld lease value is used if the lease value, passed to the
+   * {@link #dirty} is equal to zero.
+   */
+  static final long LEASE_VALUE = 600000L;
+
+  // leaseCache caches a LeaseRecord associated with a vmid
+  Hashtable leaseCache = new Hashtable();
+
+  public DGCImpl() throws RemoteException
+  {
+    super(new ObjID(ObjID.DGC_ID), 0, RMISocketFactory.getSocketFactory());
+  }
+
+  /**
+   * 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
+   */
+  public Lease dirty(ObjID[] ids, long sequenceNum, Lease lease)
+      throws RemoteException
+  {
+    VMID vmid = lease.getVMID();
+    if (vmid == null)
+      vmid = new VMID();
+
+    long leaseValue = lease.getValue();
+    if (leaseValue <= 0)
+      leaseValue = LEASE_VALUE;
+
     lease = new Lease(vmid, leaseValue);
-        synchronized(leaseCache){
-            LeaseRecord lr = (LeaseRecord)leaseCache.get(vmid);
-            if (lr != null)
-                lr.reset(leaseValue);
-            else{
-                lr = new LeaseRecord(vmid, leaseValue);
-                leaseCache.put(vmid, lr);
-            }
-        }
-        
-	return (lease);
-}
-
-public void clean(ObjID[] ids, long sequenceNum, VMID vmid, boolean strong) throws RemoteException {
-  // Not implemented
-}
+    LeaseRecord lr = (LeaseRecord) leaseCache.get(vmid);
+    if (lr != null)
+      lr.reset(leaseValue);
+    else
+      {
+        lr = new LeaseRecord(vmid, leaseValue, ids);
+        leaseCache.put(vmid, lr);
+      }
     
+    return (lease);
+  }
+
+  /**
+   * 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
+   *          calls)
+   * @param vmid the VMID of the client.
+   * @param strong make the "strong" clean call.
+   */
+  public void clean(ObjID[] ids, long sequenceNum, VMID vmid, boolean strong)
+      throws RemoteException
+  {
+    // Not implemented
+    // TODO implement
+  }
+
   /**
    * LeaseRecord associates a vmid to expireTime.
    */
-  private static class LeaseRecord{
-    private VMID vmid;
-    private long expireTime;
+  static class LeaseRecord
+  {
+    /**
+     * The lease id.
+     */
+    final VMID vmid;
+
+    /**
+     * The lease expiration time.
+     */ 
+    long expireTime;
     
-    LeaseRecord(VMID vmid, long leaseValue){
+    /**
+     * The array of ObjeID's that must be protected from being garbage
+     * collected.
+     */
+    final ObjID [] objects;
+
+    /**
+     * Create the new lease record.
+     * 
+     * @param vmid lease id.
+     * @param leaseValue lease value
+     */
+    LeaseRecord(VMID vmid, long leaseValue, ObjID [] an_objects)
+    {
       this.vmid = vmid;
       reset(leaseValue);
+      objects = an_objects;
     }
-    
-    // reset expireTime
-    void reset(long leaseValue){
+
+    /**
+     * Prolong the expiration time till current time + passed value
+     * 
+     * @param leaseValue the value after that (since the current moment)
+     * the lease should expire in the future.
+     */
+    void reset(long leaseValue)
+    {
       long l = System.currentTimeMillis();
       expireTime = l + leaseValue;
     }
-
-    boolean isExpired(){
+    
+    /**
+     * Check if the lease has been expired.
+     * 
+     * @return true if the lease has been expired, false if it is still valid.
+     */
+    boolean isExpired()
+    {
       long l = System.currentTimeMillis();
-      if ( l > expireTime)
-	return true;
+      if (l > expireTime)
+        return true;
       return false;
     }
-        
-  } //End of LeaseRecord
 
-} //End of DGCImpl
+  } // End of LeaseRecord
+
+} // End of DGCImpl