2 * Copyright (c) 2017 Red Hat, Inc. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.controller.md.sal.trace.closetracker.impl;
10 import java.util.Objects;
11 import javax.annotation.Nullable;
14 * Implementation of {@link CloseTracked} which can be used as a field in
15 * another class which implements {@link CloseTracked} and delegates its methods
18 * <p>This is useful if that class already has another parent class.
19 * If it does not, then it's typically more convenient to just extend AbstractCloseTracked.
21 * @author Michael Vorburger.ch
23 public class CloseTrackedTrait<T extends CloseTracked<T>> implements CloseTracked<T> {
25 // NB: It's important that we keep a Throwable here, and not directly the StackTraceElement[] !
26 // This is because creating a new Throwable() is a lot less expensive in terms of runtime overhead
27 // than actually calling its getStackTrace(), which we can delay until we really need to.
28 // see also e.g. https://stackoverflow.com/a/26122232/421602
29 private final @Nullable Throwable allocationContext;
30 private final CloseTrackedRegistry<T> closeTrackedRegistry;
31 private final CloseTracked<T> realCloseTracked;
33 public CloseTrackedTrait(CloseTrackedRegistry<T> transactionChainRegistry, CloseTracked<T> realCloseTracked) {
34 if (transactionChainRegistry.isDebugContextEnabled()) {
35 // NB: We're NOT doing the (expensive) getStackTrace() here just yet (only below)
36 // TODO When we're on Java 9, then instead use the new java.lang.StackWalker API..
37 this.allocationContext = new Throwable();
39 this.allocationContext = null;
41 this.realCloseTracked = Objects.requireNonNull(realCloseTracked, "realCloseTracked");
42 this.closeTrackedRegistry = Objects.requireNonNull(transactionChainRegistry, "transactionChainRegistry");
43 this.closeTrackedRegistry.add(this);
48 public StackTraceElement[] getAllocationContextStackTrace() {
49 return allocationContext != null ? allocationContext.getStackTrace() : null;
52 public void removeFromTrackedRegistry() {
53 closeTrackedRegistry.remove(this);
57 public CloseTracked<T> getRealCloseTracked() {
58 return realCloseTracked;