I am testing ClientXADataSource. 
It fails when end() is called - here is the output fromn my test program. 

Running test org.simplejta.xatests.common.Test1 
autocommit = false 
No of rows Affected 1 
autocommit = true 
No of rows Affected 1 
org.apache.derby.client.am.XaException: XAER_RMFAIL : Connection is Closed. 
at org.apache.derby.client.net.NetXAResource.throwXAException(Unknown Source) 
at org.apache.derby.client.net.NetXAResource.throwXAException(Unknown Source) 
at org.apache.derby.client.net.NetXAResource.connectionClosedFailure(Unknown Source) 
at org.apache.derby.client.net.NetXAResource.end(Unknown Source) 
at org.simplejta.xatests.common.Test1.doTest(Test1.java:52) 
at org.simplejta.tests.DerbyClientTests.main(DerbyClientTests.java:66) 
Caused by: org.apache.derby.client.am.SqlException: Connection is Closed. 
... 4 more 
Test org.simplejta.xatests.common.Test1 failed 

The test program is: 

/* 
 * Test case for multiple logical connections between start() and end(). 
 */ 
package org.simplejta.xatests.common; 

import java.sql.Connection; 
import java.sql.SQLException; 
import java.sql.Statement; 

import javax.sql.XAConnection; 
import javax.sql.XADataSource; 
import javax.transaction.xa.XAResource; 
import javax.transaction.xa.Xid; 

public class Test1 extends TestCase { 

    public void doTest(XADataSource ds) throws Exception { 

            // Get a XA connection to the underlying data source 
            XAConnection pc1 = ds.getXAConnection(); 

            // Get the XA Resource 
            XAResource xar1 = pc1.getXAResource(); 

            // Create an Xid 
            Xid xid1 = Utils.createXid(1); 

            // Start the XA transaction 
            xar1.start(xid1, XAResource.TMNOFLAGS); 

            // Get a Logical Connection 
            Connection conn1 = pc1.getConnection(); 
            System.out.println("autocommit = " + conn1.getAutoCommit()); 

            // Do something with conn1 
            doSomeWork1(conn1, 50); 

            // Close the logical connection 
            conn1.close(); 

            // Get another logical connection 
            conn1 = pc1.getConnection(); 
            System.out.println("autocommit = " + conn1.getAutoCommit()); 

            // Do something with conn1 
            doSomeWork1(conn1, 51); 

            // Close the logical connection 
            conn1.close(); 

            // END the branche 
            xar1.end(xid1, XAResource.TMSUCCESS); 

            // Prepare the RMs 
            int prp1 = xar1.prepare(xid1); 

            // Commit transaction 
            xar1.commit(xid1, false); 

            // Close physical connection 
            pc1.close(); 
    } 

    private void doSomeWork1(Connection conn, int deptno) throws SQLException { 
        Statement stmt = conn.createStatement(); 
        int cnt = stmt 
                .executeUpdate("INSERT INTO dept VALUES (" + deptno + ", 'BSD', 'LONDON')"); 
        System.out.println("No of rows Affected " + cnt); 
        stmt.close(); 
        stmt = null; 
    } 
} 


This test works fine with EmbeddedXADataSource. It also works fine with Oracle. 

Also, note that this error seems similar to the error I am getting with DB2 using the DB2 type 4 driver. 

Running test org.simplejta.xatests.common.Test1 
autocommit = false 
No of rows Affected 1 
autocommit = false 
No of rows Affected 1 
com.ibm.db2.jcc.b.de: XAER_RMFAIL : Connection is Closed. : Exception from native code during XA 
at com.ibm.db2.jcc.uw.UWXAResource.a(UWXAResource.java:695) 
at com.ibm.db2.jcc.uw.UWXAResource.a(UWXAResource.java:709) 
at com.ibm.db2.jcc.uw.UWXAResource.end(UWXAResource.java:227) 
at org.simplejta.xatests.common.Test1.doTest(Test1.java:52) 
at org.simplejta.tests.DB2Tests.main(DB2Tests.java:65) 
Caused by: com.ibm.db2.jcc.b.SqlException: Connection is Closed. 
at com.ibm.db2.jcc.uw.UWXAResource.a(UWXAResource.java:705) 
... 3 more 
Test org.simplejta.xatests.common.Test1 failed 



Curiously, the error appears to corrupt the database. Subsequent attempts to start the database gives an error. 


org.apache.derby.client.am.SqlException: DERBY SQL error: SQLCODE: -1, SQLSTATE: XJ040, SQLERRMC: tcaXJ040.CXSTB0:XSTB0.MFailed to start database 'tca', see the next exception for details.An exception was thrown during transaction abort.(server log:c:\derby\databases\derby.log) 
at org.apache.derby.client.am.Connection.completeSqlca(Unknown Source) 
at org.apache.derby.client.net.NetConnectionReply.parseRdbAccessFailed(Unknown Source) 
at org.apache.derby.client.net.NetConnectionReply.parseAccessRdbError(Unknown Source) 
at org.apache.derby.client.net.NetConnectionReply.parseACCRDBreply(Unknown Source) 
at org.apache.derby.client.net.NetConnectionReply.readAccessDatabase(Unknown Source) 
at org.apache.derby.client.net.NetConnection.readSecurityCheckAndAccessRdb(Unknown Source) 
at org.apache.derby.client.net.NetConnection.flowSecurityCheckAndAccessRdb(Unknown Source) 
at org.apache.derby.client.net.NetConnection.flowUSRIDPWDconnect(Unknown Source) 
at org.apache.derby.client.net.NetConnection.flowConnect(Unknown Source) 
at org.apache.derby.client.net.NetConnection.initialize(Unknown Source) 
at org.apache.derby.client.net.NetConnection.<init>(Unknown Source) 
at org.apache.derby.client.net.NetXAConnection.<init>(Unknown Source) 
at org.apache.derby.client.ClientPooledConnection.<init>(Unknown Source) 
at org.apache.derby.client.ClientXAConnection.<init>(Unknown Source) 
at org.apache.derby.jdbc.ClientXADataSource.getXAConnection(Unknown Source) 
at org.apache.derby.jdbc.ClientXADataSource.getXAConnection(Unknown Source)