--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/org/tmatesoft/hg/util/LogFacility.java	Fri Sep 16 05:35:32 2011 +0200
@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2011 TMate Software Ltd
+ *  
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program 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 for more details.
+ *
+ * For information on how to redistribute this software under
+ * the terms of a license other than GNU General Public License
+ * contact TMate Software at support@hg4j.com
+ */
+package org.tmatesoft.hg.util;
+
+import org.tmatesoft.hg.internal.Experimental;
+
+/**
+ * WORK IN PROGRESS
+ * 
+ * Intention of this class is to abstract away almost any log facility out there clients might be using with the <b>Hg4J</b> library, 
+ * not to be a full-fledged logging facility of its own.
+ * 
+ * Implementations may wrap platform- or application-specific loggers, e.g. {@link java.util.logging.Logger} or 
+ * <code>org.eclipse.core.runtime.ILog</code>
+ * 
+ * @author Artem Tikhomirov
+ * @author TMate Software Ltd.
+ */
+@Experimental(reason="API might get changed")
+public interface LogFacility {
+
+	boolean isDebug();
+	boolean isInfo();
+
+	// src and format never null
+	void debug(Class<?> src, String format, Object... args);
+	void info(Class<?> src, String format, Object... args);
+	void warn(Class<?> src, String format, Object... args);
+	void error(Class<?> src, String format, Object... args);
+
+	// src shall be non null, either th or message or both
+	void debug(Class<?> src, Throwable th, String message);
+	void info(Class<?> src, Throwable th, String message);
+	void warn(Class<?> src, Throwable th, String message);
+	void error(Class<?> src, Throwable th, String message);
+}