Fix ConcurrentModificationException when creating tables and executing SHOW…

Fix ConcurrentModificationException when creating tables and executing SHOW TABLES in parallel. Reported by vvoytovych@llnw.com.

h2/src/docsrc/html/changelog.html

@@ -35,6 +35,7 @@ Change Log
 </li><li>Fix ABBA deadlock between adding a constraint and the H2-Log-Writer thread.
 </li><li>Optimize IN(...) queries where the values are constant and of the same type.
 </li><li>Restore tool: the parameter "quiet" was not used and is now removed.
+</li><li>Fix ConcurrentModificationException when creating tables and executing SHOW TABLES in parallel. Reported by vvoytovych@llnw.com.
 </li></ul>
 
 <h2>Version 1.3.169 (2012-09-09)</h2>

h2/src/main/org/h2/schema/Schema.java

@@ -510,7 +510,9 @@ public class Schema extends DbObjectBase {
      * @return a (possible empty) list of all objects
      */
     public ArrayList<Table> getAllTablesAndViews() {
-        return New.arrayList(tablesAndViews.values());
+        synchronized (database) {
+            return New.arrayList(tablesAndViews.values());
+        }
     }
 
     /**