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  1. MariaDB Connector/J
  2. CONJ-245

Check connection status before executing query

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    Details

    • Type: Bug
    • Status: Closed (View Workflow)
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 1.4.0
    • Component/s: Other
    • Labels:
      None

      Description

      If a statement execute a query on a close connection a nullpointer exception is thrown :
      javax.persistence.PersistenceException: java.lang.NullPointerException
      at org.eclipse.persistence.internal.jpa.QueryImpl.getResultList(QueryImpl.java:484)
      at MariaDBTest$2.run(MariaDBTest.java:52)
      Caused by: java.lang.NullPointerException
      at org.mariadb.jdbc.internal.stream.PacketOutputStream.startPacket(PacketOutputStream.java:68)
      at org.mariadb.jdbc.internal.stream.PacketOutputStream.startPacket(PacketOutputStream.java:78)
      at org.mariadb.jdbc.internal.packet.send.SendTextQueryPacket.send(SendTextQueryPacket.java:101)
      at org.mariadb.jdbc.internal.protocol.AbstractQueryProtocol.sendQuery(AbstractQueryProtocol.java:388)
      at org.mariadb.jdbc.internal.protocol.AbstractQueryProtocol.executeQuery(AbstractQueryProtocol.java:382)
      at org.mariadb.jdbc.internal.protocol.AbstractQueryProtocol.executeQuery(AbstractQueryProtocol.java:339)
      at org.mariadb.jdbc.MariaDbStatement.execute(MariaDbStatement.java:280)
      at org.mariadb.jdbc.MariaDbStatement.executeQuery(MariaDbStatement.java:448)

      to reproduce :

      ```
      Connection connection = DriverManager.getConnection("jdbc:mariadb:/....");
      Statement statement = connection.createStatement();
      try

      { Statement otherStatement = connection.createStatement(); otherStatement.execute("QUERY"); }

      catch (SQLException e)

      { //throw connection exception (SQLState "08XXX") due to network instability //otherStatement and connection will be closed //but method continue }

      //Will throw this nullPointerException
      statement.execute("QUERY");
      ```
      The correction seem not to change the PacketOutputStream, since socket is close. The thing is to check "connected" status in the AbstractQueryProtocol, before executing a query and to throw a connection exception since connection is closed. That way, if driver is configured to support failover, a new connection will be created, if not, the statement will be closed and throw exception.

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            Assignee:
            diego dupin Diego Dupin
            Reporter:
            diego dupin Diego Dupin
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              Dates

              Created:
              Updated:
              Resolved:

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