FooComponent: check before create

Change-Id: Ie073ebc41a4c9028a1db804c57047a95f6617e47
diff --git a/apps/foo/src/main/java/org/onlab/onos/foo/FooComponent.java b/apps/foo/src/main/java/org/onlab/onos/foo/FooComponent.java
index 4439db5..b6f1eb9 100644
--- a/apps/foo/src/main/java/org/onlab/onos/foo/FooComponent.java
+++ b/apps/foo/src/main/java/org/onlab/onos/foo/FooComponent.java
@@ -157,7 +157,9 @@
             final String someTable = "admin";
             final String someKey = "long";
 
-            dbAdminService.createTable(someTable);
+            if (!dbAdminService.listTables().contains(someTable)) {
+                dbAdminService.createTable(someTable);
+            }
 
             VersionedValue vv = dbService.get(someTable, someKey);
             if (vv == null) {