1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/memory/referencePolicy.hpp Sat Dec 01 00:00:00 2007 +0000
1.3 @@ -0,0 +1,62 @@
1.4 +/*
1.5 + * Copyright 2000 Sun Microsystems, Inc. All Rights Reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
1.23 + * CA 95054 USA or visit www.sun.com if you need additional information or
1.24 + * have any questions.
1.25 + *
1.26 + */
1.27 +
1.28 +// referencePolicy is used to determine when soft reference objects
1.29 +// should be cleared.
1.30 +
1.31 +
1.32 +class ReferencePolicy : public ResourceObj {
1.33 + public:
1.34 + virtual bool should_clear_reference(oop p) { ShouldNotReachHere(); return true; }
1.35 +};
1.36 +
1.37 +class NeverClearPolicy : public ReferencePolicy {
1.38 + public:
1.39 + bool should_clear_reference(oop p) { return false; }
1.40 +};
1.41 +
1.42 +class AlwaysClearPolicy : public ReferencePolicy {
1.43 + public:
1.44 + bool should_clear_reference(oop p) { return true; }
1.45 +};
1.46 +
1.47 +class LRUCurrentHeapPolicy : public ReferencePolicy {
1.48 + private:
1.49 + jlong _max_interval;
1.50 +
1.51 + public:
1.52 + LRUCurrentHeapPolicy();
1.53 +
1.54 + bool should_clear_reference(oop p);
1.55 +};
1.56 +
1.57 +class LRUMaxHeapPolicy : public ReferencePolicy {
1.58 + private:
1.59 + jlong _max_interval;
1.60 +
1.61 + public:
1.62 + LRUMaxHeapPolicy();
1.63 +
1.64 + bool should_clear_reference(oop p);
1.65 +};
