82 lines
2.4 KiB
C++
82 lines
2.4 KiB
C++
/*
|
|
* Copyright (c) 2000, 2015, Oracle and/or its affiliates. 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.
|
|
*
|
|
* 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
|
|
* or visit www.oracle.com if you need additional information or have any
|
|
* questions.
|
|
*
|
|
*/
|
|
|
|
#ifndef SHARE_VM_GC_SHARED_REFERENCEPOLICY_HPP
|
|
#define SHARE_VM_GC_SHARED_REFERENCEPOLICY_HPP
|
|
|
|
// referencePolicy is used to determine when soft reference objects
|
|
// should be cleared.
|
|
|
|
|
|
class ReferencePolicy : public CHeapObj<mtGC> {
|
|
public:
|
|
virtual bool should_clear_reference(oop p, jlong timestamp_clock) {
|
|
ShouldNotReachHere();
|
|
return true;
|
|
}
|
|
|
|
// Capture state (of-the-VM) information needed to evaluate the policy
|
|
virtual void setup() { /* do nothing */ }
|
|
};
|
|
|
|
class NeverClearPolicy : public ReferencePolicy {
|
|
public:
|
|
virtual bool should_clear_reference(oop p, jlong timestamp_clock) {
|
|
return false;
|
|
}
|
|
};
|
|
|
|
class AlwaysClearPolicy : public ReferencePolicy {
|
|
public:
|
|
virtual bool should_clear_reference(oop p, jlong timestamp_clock) {
|
|
return true;
|
|
}
|
|
};
|
|
|
|
class LRUCurrentHeapPolicy : public ReferencePolicy {
|
|
private:
|
|
jlong _max_interval;
|
|
|
|
public:
|
|
LRUCurrentHeapPolicy();
|
|
|
|
// Capture state (of-the-VM) information needed to evaluate the policy
|
|
void setup();
|
|
virtual bool should_clear_reference(oop p, jlong timestamp_clock);
|
|
};
|
|
|
|
class LRUMaxHeapPolicy : public ReferencePolicy {
|
|
private:
|
|
jlong _max_interval;
|
|
|
|
public:
|
|
LRUMaxHeapPolicy();
|
|
|
|
// Capture state (of-the-VM) information needed to evaluate the policy
|
|
void setup();
|
|
virtual bool should_clear_reference(oop p, jlong timestamp_clock);
|
|
};
|
|
|
|
#endif // SHARE_VM_GC_SHARED_REFERENCEPOLICY_HPP
|