Index: gnu/classpath/jdwp/id/IdManager.java
===================================================================
RCS file: gnu/classpath/jdwp/id/IdManager.java
diff -N gnu/classpath/jdwp/id/IdManager.java
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ gnu/classpath/jdwp/id/IdManager.java 21 Jun 2005 18:55:53 -0000
@@ -0,0 +1,232 @@
+/* IdManager.java -- a manager for JDWP object/reference type IDs
+ Copyright (C) 2005 Free Software Foundation
+
+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., 59 Temple Place, Suite 330, Boston, MA
+02111-1307 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
+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 gnu.classpath.jdwp.id;
+
+import gnu.classpath.jdwp.exception.InvalidClassException;
+import gnu.classpath.jdwp.exception.InvalidObjectException;
+
+import java.lang.ref.Reference;
+import java.lang.ref.ReferenceQueue;
+import java.lang.ref.WeakReference;
+import java.io.DataInputStream;
+import java.io.IOException;
+import java.util.Collections;
+import java.util.Hashtable;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.WeakHashMap;
+
+/**
+ * This class manages objects and referencetypes that are reported
+ * to the debugger. All objects and referencetypes reported to the
+ * debugger should go through this manager.
+ *
+ * @author Keith Seitz (address@hidden)
+ */
+public class IdManager
+{
+ // Reference queues for invalid ObjectIds and ReferenceTypeIds
+ private ReferenceQueue _oidRefQueue;
+ private ReferenceQueue _ridRefQueue;
+
+ /* Mapping of objects (Object) to IDs (ObjectId). Table is a
+ synchronized WeakHashMap. */
+ private Map _oidTable;
+
+ /* Mapping of ID numbers (Long) to IDs (ObjectId). IDs are
+ stored as WeakReferences */
+ private Hashtable _idTable;
+
+ /* Mapping of class (Class) to IDs (ReferenceTypeId) for reference
+ types. Table is a synchronized WeakHashMap. */
+ private Map _classTable;
+
+ /* Mapping of ID numbers (Long) to reference type IDs (ReferenceTypeId).
+ IDs are stored as WeakReferences */
+ private Hashtable _ridTable;
+
+ /**
+ * Constructs a new IdManager
+ */
+ public IdManager ()
+ {
+ _oidRefQueue = new ReferenceQueue ();
+ _ridRefQueue = new ReferenceQueue ();
+ _oidTable = Collections.synchronizedMap (new WeakHashMap (50));
+ _idTable = new Hashtable (50);
+ _classTable = Collections.synchronizedMap (new WeakHashMap (20));
+ _ridTable = new Hashtable (20);
+ }
+
+ // Updates the ID tables, removing IDs whose objects/classes have
+ // been garbage collected.
+ private void _update ()
+ {
+ Reference ref;
+ while ((ref = _oidRefQueue.poll ()) != null)
+ {
+ ObjectId id = (ObjectId) ref.get ();
+ _oidTable.remove (new Long (id.getId ()));
+ }
+
+ while ((ref = _ridRefQueue.poll ()) != null)
+ {
+ ReferenceTypeId id = (ReferenceTypeId) ref.get ();
+ _ridTable.remove (new Long (id.getId ()));
+ }
+ }
+
+ /**
+ * Returns an id for the given object, adding it
+ * if it does not have an id.
+ *
+ * @param theObject the object to get an ID/add
+ * @returns the ID of the object
+ */
+ public ObjectId getId (Object theObject)
+ {
+ ObjectId id = (ObjectId) _oidTable.get (theObject);
+ if (id == null)
+ {
+ // update the tables -- this is an arbitrary place to put this
+ _update ();
+
+ // Object not found. Make new id for it
+ id = JdwpIdFactory.newId (theObject);
+ _oidTable.put (theObject, id);
+ _idTable.put (new Long (id.getId ()),
+ new WeakReference (id, _oidRefQueue));
+ }
+
+ return id;
+ }
+
+ /**
+ * Returns the JdwpId for a given ID. Unlike
+ * getId, it throws an exception if the ID is not
+ * known.
+ *
+ * @param id the numerical ID of the desired JdwpId
+ * @throws InvalidObjectException if the ID is not found
+ */
+ public ObjectId get (long id)
+ throws InvalidObjectException
+ {
+ WeakReference ref = (WeakReference) _idTable.get (new Long (id));
+ ObjectId oid = (ObjectId) ref.get ();
+ if (oid == null)
+ throw new InvalidObjectException (id);
+
+ return oid;
+ }
+
+ /**
+ * Reads a numerical ID from the stream, returning
+ * the actual ID associated with it
+ *
+ * @returns the object id
+ * @throws IOException for any errors reading from the stream
+ * @throws InvaildObjectException if ID is not found
+ */
+ public ObjectId readId (DataInputStream is)
+ throws IOException, InvalidObjectException
+ {
+ // All IDs are longs, making this really easy
+ long nid = is.readLong ();
+ return get (nid);
+ }
+
+ /**
+ * Gets the reference type id for the given class, creating
+ * a new one if it does not already have an id
+ *
+ * @param theClazz the class for which to get an ID
+ * @returns the ID of the class
+ */
+ public ReferenceTypeId getReferenceTypeId (Class clazz)
+ {
+ ReferenceTypeId id = (ReferenceTypeId)_classTable.get (clazz);
+ if (id == null)
+ {
+ // Object not found. Make new id for it
+ id = JdwpIdFactory.newReferenceTypeId (clazz);
+ _classTable.put (clazz, id);
+ _ridTable.put (new Long (id.getId ()),
+ new WeakReference (id, _ridRefQueue));
+ }
+
+ return id;
+ }
+
+ /**
+ * Returns the ReferenceTypeId for a given ID. Unlike
+ * getReferenceTypeId, it throws an exception if the ID is not
+ * known.
+ *
+ * @param id the numerical ID of the desired reference type
+ * @throws InvalidClassException if the ID is not found
+ */
+ public ReferenceTypeId getReferenceType (long id)
+ throws InvalidClassException
+ {
+ WeakReference ref = (WeakReference) _ridTable.get (new Long (id));
+ ReferenceTypeId rid = (ReferenceTypeId) ref.get ();
+ if (rid == null)
+ throw new InvalidClassException (id);
+
+ return rid;
+ }
+
+ /**
+ * Reads a numerical ID from the stream, returning
+ * the actual reference type ID associated with it
+ *
+ * @returns the JdwpId
+ * @throws IOException for any errors reading from the stream
+ * @throws InvaildObjectException if ID is not found
+ */
+ public ReferenceTypeId readReferenceTypeId (DataInputStream is)
+ throws IOException, InvalidClassException
+ {
+ // All IDs are longs, making this really easy
+ long nid = is.readLong ();
+ return getReferenceType (nid);
+ }
+}