| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.catalina.core; |
| |
| import java.util.concurrent.Executor; |
| |
| import org.apache.catalina.Container; |
| import org.apache.catalina.ContainerEvent; |
| import org.apache.catalina.ContainerListener; |
| import org.apache.catalina.Context; |
| import org.apache.catalina.Engine; |
| import org.apache.catalina.Host; |
| import org.apache.catalina.Lifecycle; |
| import org.apache.catalina.LifecycleEvent; |
| import org.apache.catalina.LifecycleListener; |
| import org.apache.catalina.Server; |
| import org.apache.catalina.Service; |
| import org.apache.catalina.connector.Connector; |
| import org.apache.coyote.ProtocolHandler; |
| import org.apache.juli.logging.Log; |
| import org.apache.juli.logging.LogFactory; |
| import org.apache.tomcat.util.res.StringManager; |
| import org.apache.tomcat.util.threads.ThreadPoolExecutor; |
| |
| /** |
| * <p> |
| * A {@link LifecycleListener} that triggers the renewal of threads in Executor |
| * pools when a {@link Context} is being stopped to avoid thread-local related |
| * memory leaks. |
| * </p> |
| * <p> |
| * Note : active threads will be renewed one by one when they come back to the |
| * pool after executing their task, see |
| * {@link org.apache.tomcat.util.threads.ThreadPoolExecutor}.afterExecute(). |
| * </p> |
| * |
| * This listener must be declared in server.xml to be active. |
| * |
| */ |
| public class ThreadLocalLeakPreventionListener implements LifecycleListener, |
| ContainerListener { |
| |
| private static final Log log = |
| LogFactory.getLog(ThreadLocalLeakPreventionListener.class); |
| |
| private volatile boolean serverStopping = false; |
| |
| /** |
| * The string manager for this package. |
| */ |
| protected static final StringManager sm = |
| StringManager.getManager(Constants.Package); |
| |
| /** |
| * Listens for {@link LifecycleEvent} for the start of the {@link Server} to |
| * initialize itself and then for after_stop events of each {@link Context}. |
| */ |
| @Override |
| public void lifecycleEvent(LifecycleEvent event) { |
| try { |
| Lifecycle lifecycle = event.getLifecycle(); |
| if (Lifecycle.AFTER_START_EVENT.equals(event.getType()) && |
| lifecycle instanceof Server) { |
| // when the server starts, we register ourself as listener for |
| // all context |
| // as well as container event listener so that we know when new |
| // Context are deployed |
| Server server = (Server) lifecycle; |
| registerListenersForServer(server); |
| } |
| |
| if (Lifecycle.BEFORE_STOP_EVENT.equals(event.getType()) && |
| lifecycle instanceof Server) { |
| // Server is shutting down, so thread pools will be shut down so |
| // there is no need to clean the threads |
| serverStopping = true; |
| } |
| |
| if (Lifecycle.AFTER_STOP_EVENT.equals(event.getType()) && |
| lifecycle instanceof Context) { |
| stopIdleThreads((Context) lifecycle); |
| } |
| } catch (Exception e) { |
| String msg = |
| sm.getString( |
| "threadLocalLeakPreventionListener.lifecycleEvent.error", |
| event); |
| log.error(msg, e); |
| } |
| } |
| |
| @Override |
| public void containerEvent(ContainerEvent event) { |
| try { |
| String type = event.getType(); |
| if (Container.ADD_CHILD_EVENT.equals(type)) { |
| processContainerAddChild(event.getContainer(), |
| (Container) event.getData()); |
| } else if (Container.REMOVE_CHILD_EVENT.equals(type)) { |
| processContainerRemoveChild(event.getContainer(), |
| (Container) event.getData()); |
| } |
| } catch (Exception e) { |
| String msg = |
| sm.getString( |
| "threadLocalLeakPreventionListener.containerEvent.error", |
| event); |
| log.error(msg, e); |
| } |
| |
| } |
| |
| private void registerListenersForServer(Server server) { |
| for (Service service : server.findServices()) { |
| Engine engine = (Engine) service.getContainer(); |
| engine.addContainerListener(this); |
| registerListenersForEngine(engine); |
| } |
| |
| } |
| |
| private void registerListenersForEngine(Engine engine) { |
| for (Container hostContainer : engine.findChildren()) { |
| Host host = (Host) hostContainer; |
| host.addContainerListener(this); |
| registerListenersForHost(host); |
| } |
| } |
| |
| private void registerListenersForHost(Host host) { |
| for (Container contextContainer : host.findChildren()) { |
| Context context = (Context) contextContainer; |
| registerContextListener(context); |
| } |
| } |
| |
| private void registerContextListener(Context context) { |
| context.addLifecycleListener(this); |
| } |
| |
| protected void processContainerAddChild(Container parent, Container child) { |
| if (log.isDebugEnabled()) |
| log.debug("Process addChild[parent=" + parent + ",child=" + child + |
| "]"); |
| |
| if (child instanceof Context) { |
| registerContextListener((Context) child); |
| } else if (child instanceof Engine) { |
| registerListenersForEngine((Engine) child); |
| } else if (child instanceof Host) { |
| registerListenersForHost((Host) child); |
| } |
| |
| } |
| |
| protected void processContainerRemoveChild(Container parent, |
| Container child) { |
| |
| if (log.isDebugEnabled()) |
| log.debug("Process removeChild[parent=" + parent + ",child=" + |
| child + "]"); |
| |
| if (child instanceof Context) { |
| Context context = (Context) child; |
| context.removeLifecycleListener(this); |
| } else if (child instanceof Host || child instanceof Engine) { |
| child.removeContainerListener(this); |
| } |
| } |
| |
| /** |
| * Updates each ThreadPoolExecutor with the current time, which is the time |
| * when a context is being stopped. |
| * |
| * @param context |
| * the context being stopped, used to discover all the Connectors |
| * of its parent Service. |
| */ |
| private void stopIdleThreads(Context context) { |
| if (serverStopping) return; |
| |
| if (context instanceof StandardContext && |
| !((StandardContext) context).getRenewThreadsWhenStoppingContext()) { |
| log.debug("Not renewing threads when the context is stopping, " |
| + "it is configured not to do it."); |
| return; |
| } |
| |
| Engine engine = (Engine) context.getParent().getParent(); |
| Service service = engine.getService(); |
| Connector[] connectors = service.findConnectors(); |
| if (connectors != null) { |
| for (Connector connector : connectors) { |
| ProtocolHandler handler = connector.getProtocolHandler(); |
| Executor executor = null; |
| if (handler != null) { |
| executor = handler.getExecutor(); |
| } |
| |
| if (executor instanceof ThreadPoolExecutor) { |
| ThreadPoolExecutor threadPoolExecutor = |
| (ThreadPoolExecutor) executor; |
| threadPoolExecutor.contextStopping(); |
| } else if (executor instanceof StandardThreadExecutor) { |
| StandardThreadExecutor stdThreadExecutor = |
| (StandardThreadExecutor) executor; |
| stdThreadExecutor.contextStopping(); |
| } |
| |
| } |
| } |
| } |
| } |