Index: lams_tool_chat/src/java/org/lamsfoundation/lams/tool/chat/util/ChatMessageFilter.java
===================================================================
diff -u
--- lams_tool_chat/src/java/org/lamsfoundation/lams/tool/chat/util/ChatMessageFilter.java	(revision 0)
+++ lams_tool_chat/src/java/org/lamsfoundation/lams/tool/chat/util/ChatMessageFilter.java	(revision 3f2f66ee045baee864813b60e960478908341832)
@@ -0,0 +1,57 @@
+/****************************************************************
+ * Copyright (C) 2005 LAMS Foundation (http://lamsfoundation.org)
+ * =============================================================
+ * License Information: http://lamsfoundation.org/licensing/lams/2.0/
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2.0 
+ * as published by the Free Software Foundation.
+ * 
+ * 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.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
+ * USA
+ * 
+ * http://www.gnu.org/licenses/gpl.txt
+ * ****************************************************************
+ */
+
+/* $Id$ */
+
+package org.lamsfoundation.lams.tool.chat.util;
+
+import java.util.regex.Pattern;
+
+import org.lamsfoundation.lams.tool.chat.model.Chat;
+
+public class ChatMessageFilter {
+
+	private Pattern pattern;
+
+	public ChatMessageFilter(Chat chat) {
+		this.pattern = null;
+		String regex = chat.getFilterKeywords();
+		if (regex != null) {
+			// constructing regex
+			regex = regex.replaceAll("[" + "\\(" + "\\)" + "\\[" + "\\]"
+					+ "\\{" + "\\}" + "\\\\" + "\\^" + "\\$" + "\\|" + "\\?"
+					+ "\\*" + "\\+" + "\\." + "]+", " ");
+			regex = regex.replaceAll("[\\s]+", " ");
+			regex = regex.trim();
+			regex = regex.replaceAll(" ", "|");
+
+			if (regex.length() != 0) {
+				this.pattern = Pattern.compile(regex);
+			}
+		}
+	}
+
+	public Pattern getPattern() {
+		return this.pattern;
+	}
+}