--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/sun/security/pkcs11/Session.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,111 @@
+/*
+ * Copyright 2003-2005 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code 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
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package sun.security.pkcs11;
+
+import java.util.*;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import java.security.*;
+
+import sun.security.pkcs11.wrapper.*;
+
+/**
+ * A session object. Sessions are obtained via the SessionManager,
+ * see there for details. Most code will only ever need one method in
+ * this class, the id() method to obtain the session id.
+ *
+ * @author  Andreas Sterbenz
+ * @since   1.5
+ */
+final class Session implements Comparable<Session> {
+
+    // time after which to close idle sessions, in milliseconds (3 minutes)
+    private final static long MAX_IDLE_TIME = 3 * 60 * 1000;
+
+    // token instance
+    final Token token;
+
+    // session id
+    private final long id;
+
+    // number of objects created within this session
+    private final AtomicInteger createdObjects;
+
+    // time this session was last used
+    // not synchronized/volatile for performance, so may be unreliable
+    // this could lead to idle sessions being closed early, but that is harmless
+    private long lastAccess;
+
+    Session(Token token, long id) {
+        this.token = token;
+        this.id = id;
+        createdObjects = new AtomicInteger();
+        id();
+    }
+
+    public int compareTo(Session other) {
+        if (this.lastAccess == other.lastAccess) {
+            return 0;
+        } else {
+            return (this.lastAccess < other.lastAccess) ? -1 : 1;
+        }
+    }
+
+    boolean isLive(long currentTime) {
+        return currentTime - lastAccess < MAX_IDLE_TIME;
+    }
+
+    long idInternal() {
+        return id;
+    }
+
+    long id() {
+        if (token.isPresent(this) == false) {
+            throw new ProviderException("Token has been removed");
+        }
+        lastAccess = System.currentTimeMillis();
+        return id;
+    }
+
+    void addObject() {
+        int n = createdObjects.incrementAndGet();
+        // XXX update statistics in session manager if n == 1
+    }
+
+    void removeObject() {
+        int n = createdObjects.decrementAndGet();
+        if (n == 0) {
+            token.sessionManager.demoteObjSession(this);
+        } else if (n < 0) {
+            throw new ProviderException("Internal error: objects created " + n);
+        }
+    }
+
+    boolean hasObjects() {
+        return createdObjects.get() != 0;
+    }
+
+}