| /* |
| * Copyright (c) 2016, 2019, 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. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package jdk.jfr.internal.consumer; |
| |
| import jdk.jfr.internal.LongMap; |
| |
| /** |
| * Holds mapping between a set of keys and their corresponding object. |
| * |
| * If the type is a known type, i.e. {@link RecordedThread}, an |
| * {@link ObjectFactory} can be supplied which will instantiate a typed object. |
| */ |
| final class ConstantMap { |
| |
| private static final int RESOLUTION_FINISHED = 0; |
| private static final int RESOLUTION_STARTED = 1; |
| public static final ConstantMap EMPTY = new ConstantMap(); |
| |
| // A temporary placeholder, so objects can |
| // reference themselves (directly, or indirectly), |
| // when making a transition from numeric id references |
| // to normal Java references. |
| private final static class Reference { |
| private final long key; |
| private final ConstantMap pool; |
| |
| Reference(ConstantMap pool, long key) { |
| this.pool = pool; |
| this.key = key; |
| } |
| |
| Object resolve() { |
| return pool.get(key); |
| } |
| |
| public String toString() { |
| return "ref: " + pool.name + "[" + key + "]"; |
| } |
| } |
| |
| final ObjectFactory<?> factory; |
| final String name; |
| |
| private final LongMap<Object> objects; |
| |
| private boolean resolving; |
| private boolean allResolved; |
| |
| private ConstantMap() { |
| this(null, "<empty>"); |
| allResolved = true; |
| } |
| |
| ConstantMap(ObjectFactory<?> factory, String name) { |
| this.name = name; |
| this.objects = new LongMap<>(2); |
| this.factory = factory; |
| } |
| |
| Object get(long id) { |
| // fast path, all objects in pool resolved |
| if (allResolved) { |
| return objects.get(id); |
| } |
| // referenced from a pool, deal with this later |
| if (!resolving) { |
| return new Reference(this, id); |
| } |
| |
| // should always have a value |
| Object value = objects.get(id); |
| if (value == null) { |
| // unless is 0 which is used to represent null |
| if (id == 0) { |
| return null; |
| } |
| throw new InternalError("Missing object id=" + id + " in pool " + name + ". All ids should reference object"); |
| } |
| |
| // id is resolved (but not the whole pool) |
| if (objects.isSetId(id, RESOLUTION_FINISHED)) { |
| return value; |
| } |
| |
| // resolving ourself, abort to avoid infinite recursion |
| if (objects.isSetId(id, RESOLUTION_STARTED)) { |
| return null; |
| } |
| |
| // mark id as STARTED if we should |
| // come back during object resolution |
| objects.setId(id, RESOLUTION_STARTED); |
| |
| // resolve object! |
| Object resolved = resolve(value); |
| |
| // mark id as FINISHED |
| objects.setId(id, RESOLUTION_FINISHED); |
| |
| // if a factory exists, convert to RecordedThread. |
| // RecordedClass etc. and store back results |
| if (factory != null) { |
| Object factorized = factory.createObject(id, resolved); |
| objects.put(id, factorized); |
| return factorized; |
| } else { |
| objects.put(id, resolved); |
| return resolved; |
| } |
| } |
| |
| private static Object resolve(Object o) { |
| if (o instanceof Reference) { |
| return resolve(((Reference) o).resolve()); |
| } |
| if (o != null && o.getClass().isArray()) { |
| final Object[] array = (Object[]) o; |
| for (int i = 0; i < array.length; i++) { |
| Object element = array[i]; |
| array[i] = resolve(element); |
| } |
| return array; |
| } |
| return o; |
| } |
| |
| public void resolve() { |
| objects.forEachKey(k -> get(k)); |
| } |
| |
| public void put(long key, Object value) { |
| objects.put(key, value); |
| } |
| |
| public void setResolving() { |
| resolving = true; |
| allResolved = false; |
| } |
| |
| public void setResolved() { |
| allResolved = true; |
| resolving = false; |
| } |
| |
| public String getName() { |
| return name; |
| } |
| |
| public Object getResolved(long id) { |
| return objects.get(id); |
| } |
| |
| public void putResolved(long id, Object object) { |
| objects.put(id, object); |
| objects.setId(id, RESOLUTION_FINISHED); |
| } |
| |
| public void setAllResolved(boolean allResolved) { |
| this.allResolved = allResolved; |
| } |
| } |