| /* |
| * Copyright (c) 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. |
| */ |
| |
| import java.lang.management.GarbageCollectorMXBean; |
| import java.lang.management.ManagementFactory; |
| import java.util.Arrays; |
| import java.util.Objects; |
| |
| /** |
| * Helper class with enum representation of GC types. |
| */ |
| public final class GCTypes { |
| |
| private static <T extends GCType> T getCurrentGCType(Class<T> type) { |
| return ManagementFactory.getGarbageCollectorMXBeans().stream() |
| .map(bean -> getGCTypeByName(type, bean.getName())) |
| .filter(Objects::nonNull) |
| .findFirst() |
| .orElse(null); |
| } |
| |
| private static <T extends GCType> T getGCTypeByName(Class<T> type, String name) { |
| return Arrays.stream(type.getEnumConstants()) |
| .filter(e -> e.getGCName().equals(name)) |
| .findFirst() |
| .orElse(null); |
| } |
| |
| private static <T extends GCType> GarbageCollectorMXBean getGCBeanByType(Class<T> type) { |
| return ManagementFactory.getGarbageCollectorMXBeans().stream() |
| .filter(bean -> Arrays.stream(type.getEnumConstants()) |
| .filter(enumName -> enumName.getGCName().equals(bean.getName())) |
| .findFirst() |
| .isPresent() |
| ) |
| .findFirst() |
| .orElse(null); |
| } |
| |
| /** |
| * Helper interface used by GCTypes static methods |
| * to get gcTypeName field of *GCType classes. |
| */ |
| private interface GCType { |
| |
| String getGCName(); |
| } |
| |
| public static enum YoungGCType implements GCType { |
| DefNew("Copy"), |
| ParNew("ParNew"), |
| PSNew("PS Scavenge"), |
| G1("G1 Young Generation"); |
| |
| @Override |
| public String getGCName() { |
| return gcTypeName; |
| } |
| private final String gcTypeName; |
| |
| private YoungGCType(String name) { |
| gcTypeName = name; |
| } |
| |
| public static YoungGCType getYoungGCType() { |
| return GCTypes.getCurrentGCType(YoungGCType.class); |
| } |
| |
| public static GarbageCollectorMXBean getYoungGCBean() { |
| return GCTypes.getGCBeanByType(YoungGCType.class); |
| } |
| } |
| |
| public static enum OldGCType implements GCType { |
| Serial("MarkSweepCompact"), |
| CMS("ConcurrentMarkSweep"), |
| PSOld("PS MarkSweep"), |
| G1("G1 Old Generation"); |
| |
| private final String gcTypeName; |
| |
| private OldGCType(String name) { |
| gcTypeName = name; |
| } |
| |
| public static OldGCType getOldGCType() { |
| return GCTypes.getCurrentGCType(OldGCType.class); |
| } |
| |
| @Override |
| public String getGCName() { |
| return gcTypeName; |
| } |
| } |
| } |