SQLNonTransientConnectionException: No current connection, in my application while interacting with Derby database - database

Question

I implemented derby data base in my application to save my data,and I am getting this exception in retrieval of result set form select query in Derby database.
To establish the connection I use connection string as:
I establish connection using this method:
I declare this method in class Connection.java:
public synchronized Connection createConnection() throws Exception {
Connection rescon = null;
try {
if (this.dbuser == null) {
rescon = DriverManager.getConnection(this.URI + ";create=true");
} else {
rescon = DriverManager.getConnection(this.URI + ";create=true",
this.dbuser, this.dbpass);
}
// new connection in connection pool created
} catch (SQLException e) {
final String stackNum = Utility.exceptionHandler(e);
throw new Exception("Exception get during Connection - " + e.getMessage());
}
return rescon;
}
I used this method as and create connection, create connection during intraction using string:
private Connection objConnection = null;
objConnectionpool = new Connection("jdbc:derby:" + Folder.getAbsolutePath() + "/myapplication" + sFileName, null, null, "org.apache.derby.jdbc.EmbeddedDriver");
objConnection = objConnectionpool.createNewConnection();
I am getting exception in execution of query:
sQuery = "select value,reason from " + TableNm + " where fileName ='" + FileName + "' AND type='"+Type+"' AND status ='remaining'";
during processing and interaction with Derby database we might update as well get the data from the database:
I perform setAutoCommit as false before inserting in the database
objConnection.setAutoCommit(false);
after insertion:
ps = objConnection.prepareStatement(sQuery);
rs = ps.executeQuery();
objConnection.commit();
objConnection.setAutoCommit(true);
I am getting Exception as
java.sql.SQLNonTransientConnectionException: No current connection.
at org.apache.derby.impl.jdbc.SQLExceptionFactory40.getSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.Util.newEmbedSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.Util.newEmbedSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.Util.noCurrentConnection(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedConnection.checkIfClosed(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedConnection.setupContextStack(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedConnection.prepareStatement(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedConnection.prepareStatement(Unknown Source)
at com.myapplication.c.aw.a(Unknown Source)
at com.myapplication.c.aw.a(Unknown Source)
at com.myapplication.main.avd.run(Unknown Source)
Caused by: java.sql.SQLException: No current connection.
at org.apache.derby.impl.jdbc.SQLExceptionFactory.getSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.SQLExceptionFactory40.wrapArgsForTransportAcrossDRDA(Unknown Source)
... 11 more

Answer 1

Found this via Google.
I had the same problem and found my answer in this sample application: http://db.apache.org/derby/docs/10.4/devguide/rdevcsecure26537.html
// force garbage collection to unload the EmbeddedDriver
// so Derby can be restarted
System.gc();
Works perfectly now.