Rely on string builder to avoid to slow the execution.

Change-Id: I4fe4029b7a6a3da770b26c9867acfc01bc9997a5
Signed-off-by: jeremie.tatibouet <jeremie.tatibouet@cea.fr>
diff --git a/bundles/core/engines/org.eclipse.papyrus.moka.timedfuml/src/org/eclipse/papyrus/moka/timedfuml/actions/_displayCurrentTimeAction.java b/bundles/core/engines/org.eclipse.papyrus.moka.timedfuml/src/org/eclipse/papyrus/moka/timedfuml/actions/_displayCurrentTimeAction.java
index cffdcb4..1a29b94 100644
--- a/bundles/core/engines/org.eclipse.papyrus.moka.timedfuml/src/org/eclipse/papyrus/moka/timedfuml/actions/_displayCurrentTimeAction.java
+++ b/bundles/core/engines/org.eclipse.papyrus.moka.timedfuml/src/org/eclipse/papyrus/moka/timedfuml/actions/_displayCurrentTimeAction.java
@@ -38,9 +38,15 @@
 		if (out == null) {
 			this.out = System.out;
 		}
-		String message = "Step: " + this.step + ", Current time: " + DEScheduler.getInstance().getCurrentTime() + "\n";
+		StringBuilder builder = new StringBuilder();
+		builder.append("\n------------------------------------------------------------------------\n");
+		builder.append("Step: ");
+		builder.append(this.step);
+		builder.append(", Current time: ");
+		builder.append(DEScheduler.getInstance().getCurrentTime());
+		builder.append("\n------------------------------------------------------------------------\n");
 		try {
-			out.write(message.getBytes());
+			out.write(builder.toString().getBytes());
 		} catch (IOException e) {
 
 		}