[OPENJPA-2789] JDBC connection not closed when running named query in explicitly opened connection

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 2.4.3
• Fix Version/s: 3.2.0
• Component/s: jdbc, kernel
• Environment: Windows 7, Java 8 64 Bit, openJPA 2.4.3, maven 3.6.1
• Assignee: Mark Struberg
• Reporter: Wolfgang Rupprath
• Created: 18/Jun/19 16:33
• Updated: 14/May/21 08:16
• Resolved: 18/Apr/21 21:11

Description

When executing a named query against a database within an explicitly opened transaction, after 10 successful executions the program hangs.

The problem occured when we started migrating from openJPA 2.2.0 to 2.4.3

I have tested against DB2 and Oracle databases with the same results. I suspect the problem arises for any relational DB.

I have attached a simple maven project that will demonstrate the bug.

Under 2.2.0, the test runs fine.

When the query is changed to a native query, the test runs fine.

Debugging the openJPA code, I found suspicious code in class org.apache.openjpa.jdbc.kernel.JDBCStoreQuery, method executeBulkOperation, line 587:

            try {
         if (conn.getAutoCommit())
                       conn.close();
         } catch (SQLException se) {}{{}}

The connection in case will not be returned to the pool as the conn.close() is not executed wthin a transaction. So when committing, the ref count will not be zero when the transaction ends and the underlying JDBC connection will not be closed.