Closing a Statement or PreparedStatement at the same time as executing a…

Closing a Statement or PreparedStatement at the same time as executing a statement could throw a strange exception.

h2/src/main/org/h2/jdbc/JdbcConnection.java

@@ -297,11 +297,15 @@ public class JdbcConnection extends TraceObject implements Connection {
             if (session == null) {
                 return;
             }
-            synchronized (session) {
+            session.cancel();
             if (executingStatement != null) {
+                try {
                     executingStatement.cancel();
+                } catch (NullPointerException e) {
+                    // ignore
                 }
-                session.cancel();
+            }
+            synchronized (session) {
                 try {
                     if (!session.isClosed()) {
                         try {

h2/src/test/org/h2/test/unit/TestConcurrent.java

@@ -82,10 +82,13 @@ public class TestConcurrent extends TestBase {
             conn.close();
             t.join();
             SQLException e = ex[0];
-            if (e != null && ErrorCode.OBJECT_CLOSED != e.getErrorCode()) {
+            if (e != null) {
+                if (ErrorCode.OBJECT_CLOSED != e.getErrorCode() &&
+                        ErrorCode.STATEMENT_WAS_CANCELED != e.getErrorCode()) {
                     throw e;
                 }
             }
         }
+    }
 
 }