Index: trunk/EventBenchConsole/src/de/ugoe/cs/eventbench/web/commands/CMDloadSessionsFromClickstream.java
===================================================================
--- trunk/EventBenchConsole/src/de/ugoe/cs/eventbench/web/commands/CMDloadSessionsFromClickstream.java	(revision 235)
+++ trunk/EventBenchConsole/src/de/ugoe/cs/eventbench/web/commands/CMDloadSessionsFromClickstream.java	(revision 236)
@@ -34,6 +34,6 @@
 			throw new InvalidParameterException();
 		}
-		String source = (String) parameters.get(0);
-		String sequencesName = (String) parameters.get(1);
+		String source;
+		String sequencesName;
 		String serverUrl = null;
 		int timeout = -1;
@@ -42,17 +42,23 @@
 		boolean generateFrequentUsers = false;
 		int frequentUserThreshold = 20;
-		if (parameters.size() >= 3) {
-			serverUrl = (String) parameters.get(2);
-		}
-		if (parameters.size() >= 6) {
-			timeout = Integer.parseInt((String) parameters.get(3));
-			minLength = Integer.parseInt((String) parameters.get(4));
-			maxLength = Integer.parseInt((String) parameters.get(5));
-		}
-		if (parameters.size() >= 8) {
-			generateFrequentUsers = Boolean.parseBoolean((String) parameters
-					.get(6));
-			frequentUserThreshold = Integer
-					.parseInt((String) parameters.get(7));
+		try {
+			source = (String) parameters.get(0);
+			sequencesName = (String) parameters.get(1);
+			if (parameters.size() >= 3) {
+				serverUrl = (String) parameters.get(2);
+			}
+			if (parameters.size() >= 6) {
+				timeout = Integer.parseInt((String) parameters.get(3));
+				minLength = Integer.parseInt((String) parameters.get(4));
+				maxLength = Integer.parseInt((String) parameters.get(5));
+			}
+			if (parameters.size() >= 8) {
+				generateFrequentUsers = Boolean
+						.parseBoolean((String) parameters.get(6));
+				frequentUserThreshold = Integer.parseInt((String) parameters
+						.get(7));
+			}
+		} catch (Exception e) {
+			throw new InvalidParameterException();
 		}
 
@@ -89,7 +95,10 @@
 					.getFrequentUserSequences();
 			for (int i = 0; i < frequentUserIDs.size(); i++) {
-				GlobalDataContainer.getInstance().addData(
+				if (GlobalDataContainer.getInstance().addData(
 						sequencesName + "_" + frequentUserIDs.get(i),
-						frequentUserSessions.get(i));
+						frequentUserSessions.get(i))) {
+					Console.traceln("Old data \"" + sequencesName
+							+ "\" overwritten");
+				}
 			}
 		}