X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=liblttng-ust-java-agent%2Fjava%2Flttng-ust-agent-common%2Forg%2Flttng%2Fust%2Fagent%2Ffilter%2FIFilterChangeListener.java;fp=liblttng-ust-java-agent%2Fjava%2Flttng-ust-agent-common%2Forg%2Flttng%2Fust%2Fagent%2Ffilter%2FIFilterChangeListener.java;h=90883c7a4c02e15d00b319d9c5ea135da86d769b;hb=4fb826b158cbd2cea8f4a91457f49417c261777d;hp=0000000000000000000000000000000000000000;hpb=3daf5cba66edbd7d8b608be1372a1665189b3c67;p=lttng-ust.git

diff --git a/liblttng-ust-java-agent/java/lttng-ust-agent-common/org/lttng/ust/agent/filter/IFilterChangeListener.java b/liblttng-ust-java-agent/java/lttng-ust-agent-common/org/lttng/ust/agent/filter/IFilterChangeListener.java
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+/*
+ * Copyright (C) 2015 - EfficiOS Inc., Alexandre Montplaisir <alexmonthy@efficios.com>
+ *
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License, version 2.1 only,
+ * as published by the Free Software Foundation.
+ *
+ * This library 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 Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+package org.lttng.ust.agent.filter;
+
+import org.lttng.ust.agent.session.EventRule;
+
+/**
+ * Filter notification listener interface.
+ * <p>
+ * Applications wanting to be notified of event filtering rule changes should
+ * implement this interface, then register their listener using
+ * {@link FilterChangeNotifier#registerListener}.
+ * </p>
+ * <p>
+ * The callbacks defined in this interface will be called whenever an event rule
+ * is added or removed. The manager will take care of the reference-counting in
+ * case multiple tracing sessions enable the exact same rules. For example, the
+ * {@link #eventRuleRemoved} callback is only called when there are no more
+ * session interested into it.
+ * </p>
+ * <p>
+ * Do not forget to unregister the listener after use, using
+ * {@link FilterChangeNotifier#unregisterListener}. If you do not, or if
+ * you use an anonymous listener for example, these will remain attached until
+ * the complete shutdown of the application.
+ * </p>
+ * <p>
+ * Only one thread is used to dispatch notifications, sequentially. This means
+ * that if a callback hangs it will prevent other listeners from receiving
+ * notifications. Please take care of not blocking inside the listener
+ * callbacks, and use separate threads for potentially long or blocking
+ * operations.
+ * </p>
+ *
+ * @author Alexandre Montplaisir
+ */
+public interface IFilterChangeListener {
+
+	/**
+	 * Notification that a new event rule is now enabled in the tracing
+	 * sessions.
+	 *
+	 * @param rule
+	 *            The event rule that was enabled
+	 */
+	void eventRuleAdded(EventRule rule);
+
+	/**
+	 * Notification that an existing event rule is now disabled in the tracing
+	 * sessions.
+	 *
+	 * @param rule
+	 *            The event rule that was disabled
+	 */
+	void eventRuleRemoved(EventRule rule);
+}