make the code read easier

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

@@ -112,14 +112,23 @@ public class Sequence extends SchemaObjectBase {
      * @param session the session
      */
     public synchronized void flush(Session session) {
-        Session sysSession = database.getSystemSession();
         if (session == null || !database.isSysTableLocked()) {
             // this session may not lock the sys table (except if it already has locked it)
             // because it must be committed immediately
             // otherwise other threads can not access the sys table.
-            session = sysSession;
+            Session sysSession = database.getSystemSession();
+            synchronized (sysSession) {
+                flushInternal(sysSession);
+                sysSession.commit(false);
             }
+        } else {
             synchronized (session) {
+                flushInternal(session);
+            }
+        }
+    }
+
+    private void flushInternal(Session session) {
         // just for this case, use the value with the margin for the script
         long realValue = value;
         try {
@@ -128,12 +137,6 @@ public class Sequence extends SchemaObjectBase {
         } finally {
             value = realValue;
         }
-            if (session == sysSession) {
-                // if the system session is used,
-                // the transaction must be committed immediately
-                sysSession.commit(false);
-            }
-        }
     }
     
     /**