com.atomikos.datasource.xa.TemporaryXATransactionalResource Maven / Gradle / Ivy
/**
* Copyright (C) 2000-2017 Atomikos
*
* LICENSE CONDITIONS
*
* See http://www.atomikos.com/Main/WhichLicenseApplies for details.
*/
package com.atomikos.datasource.xa;
import javax.transaction.xa.XAException;
import javax.transaction.xa.XAResource;
import com.atomikos.datasource.ResourceException;
import com.atomikos.logging.Logger;
import com.atomikos.logging.LoggerFactory;
/**
* A class for temporary resources. This is useful for configurations that don't
* register any XATransactionalResources in advance (zero setup). These cases
* require a dynamic and temporary XATransactionalResource to be added. This
* resource will be closed with the connection it is created on, and therefore
* is temporary.
*/
public class TemporaryXATransactionalResource extends XATransactionalResource
{
private static final Logger LOGGER = LoggerFactory.createLogger(TemporaryXATransactionalResource.class);
/**
* Max length in bytes of the resource name
*/
private static final int MAX_BYTES = 45;
/**
* Truncates name to fit in 45 bytes
* @param name
* @return
*/
private static final String truncateNameTo45Bytes ( String name )
{
String ret = name;
if ( ret.getBytes().length > MAX_BYTES ) {
ret = name.substring ( 0 , MAX_BYTES );
}
//still too long? -> must be double-byte encoding
//so halve bytes
if ( ret.getBytes().length > MAX_BYTES ) {
ret = name.substring ( 0 , MAX_BYTES / 2 );
}
return ret;
}
public TemporaryXATransactionalResource ( XAResource xares )
{
super ( truncateNameTo45Bytes ( String.valueOf(xares.hashCode()) ) );
xares_ = xares;
// get xa resource a first time, to
// so that needsRefresh() means that the
// connection is closed (as opposed to not inited)
getXAResource ();
try {
if ( !xares.isSameRM ( xares ) )
LOGGER.logWarning("XAResource " + xares + " of class "
+ xares.getClass ().getName ()
+ " does not correctly implement isSameRM(): "
+ "use explicit resource registration to save memory.");
} catch ( XAException e ) {
// ignore: this is vanilla code anyway
}
}
/**
* @see com.atomikos.datasource.xa.XATransactionalResource#refreshXAConnection()
*/
protected XAResource refreshXAConnection () throws ResourceException
{
// return the same instance at all times, since there is no connection
// factory for temporary resources
return xares_;
}
public boolean isClosed ()
{
return needsRefresh ();
}
}