| /* |
| * Copyright (c) 2016, 2018, 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. |
| */ |
| |
| package sun.hotspot.gc; |
| |
| import sun.hotspot.WhiteBox; |
| |
| /** |
| * API to obtain information about selected and supported Garbage Collectors |
| * retrieved from the VM with the WhiteBox API. |
| */ |
| public enum GC { |
| /* |
| * Enum values must match CollectedHeap::Name |
| */ |
| Serial(1), |
| Parallel(2), |
| ConcMarkSweep(3), |
| G1(4), |
| Epsilon(5), |
| Z(6), |
| Shenandoah(7); |
| |
| private static final WhiteBox WB = WhiteBox.getWhiteBox(); |
| |
| private final int name; |
| |
| private GC(int name) { |
| this.name = name; |
| } |
| |
| /** |
| * @return true if this GC is supported by the VM, i.e., it is built into the VM. |
| */ |
| public boolean isSupported() { |
| return WB.isGCSupported(name); |
| } |
| |
| /** |
| * @return true if this GC is currently selected/used |
| */ |
| public boolean isSelected() { |
| return WB.isGCSelected(name); |
| } |
| |
| /** |
| * @return true if GC was selected ergonomically, as opposed |
| * to being explicitly specified on the command line |
| */ |
| public static boolean isSelectedErgonomically() { |
| return WB.isGCSelectedErgonomically(); |
| } |
| |
| /** |
| * @return the selected GC. |
| */ |
| public static GC selected() { |
| for (GC gc : values()) { |
| if (gc.isSelected()) { |
| return gc; |
| } |
| } |
| throw new IllegalStateException("No selected GC found"); |
| } |
| } |