/*
* Copyright 2000-2008, Atomikos (http://www.atomikos.com)
*
* This code ("Atomikos TransactionsEssentials"), by itself,
* is being distributed under the
* Apache License, Version 2.0 ("License"), a copy of which may be found at
* http://www.atomikos.com/licenses/apache-license-2.0.txt .
* You may not use this file except in compliance with the License.
*
* While the License grants certain patent license rights,
* those patent license rights only extend to the use of
* Atomikos TransactionsEssentials by itself.
*
* This code (Atomikos TransactionsEssentials) contains certain interfaces
* in package (namespace) com.atomikos.icatch
* (including com.atomikos.icatch.Participant) which, if implemented, may
* infringe one or more patents held by Atomikos.
* It should be appreciated that you may NOT implement such interfaces;
* licensing to implement these interfaces must be obtained separately from Atomikos.
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
*
*/
package com.atomikos.jdbc.nonxa;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import javax.sql.PooledConnection;
import com.atomikos.icatch.CompositeTransaction;
import com.atomikos.icatch.CompositeTransactionManager;
import com.atomikos.icatch.HeuristicMessage;
import com.atomikos.icatch.jta.TransactionManagerImp;
import com.atomikos.icatch.system.Configuration;
/**
*
*
*
* A dynamic proxy class that wraps JDBC local connections to enable them for
* JTA transactions and the J2EE programming model: different modules in the
* same thread (and transaction) can get a connection from the datasource, and
* rollback will undo all that work.
*
*
*
*/
class ThreadLocalConnection implements InvocationHandler
{
private final static List NON_TRANSACTIONAL_METHOD_NAMES = Arrays.asList(new String[] {
"equals",
"hashCode",
"notify",
"notifyAll",
"toString",
"wait"
});
private int useCount;
// incremented by 1 for every time this connection is gotten
private Connection wrapped;
// the wrapped JDBC Connection
private NonXAPooledConnectionImp pooledConnection;
// the PooledConnection to which we belong
private CompositeTransaction transaction;
// not null iff we are in an active tx
private boolean stale;
// true if underlying connection is back in pool
private NonXAParticipant participant;
// the participant; kept here to add heuristic msgs to
// note: this will be null for non-transactional use!
static Object newInstance ( NonXAPooledConnectionImp pooledConnection )
throws SQLException
{
Object obj = pooledConnection.getConnection ();
Set interfaces = getAllImplementedInterfaces ( obj.getClass() );
Class[] interfaceClasses = ( Class[] ) interfaces.toArray ( new Class[0] );
return java.lang.reflect.Proxy.newProxyInstance ( obj.getClass ()
.getClassLoader (), interfaceClasses,
new ThreadLocalConnection ( pooledConnection ) );
}
//FIXED ISSUE 10080
static Set getAllImplementedInterfaces ( Class clazz )
{
Set ret = null;
if ( clazz.getSuperclass() != null ) {
//if superclass exists: first add the superclass interfaces!!!
ret = getAllImplementedInterfaces ( clazz.getSuperclass() );
}
else {
//no superclass: start with empty set
ret = new HashSet();
}
//add the interfaces in this class
Class[] interfaces = clazz.getInterfaces();
for ( int i = 0 ; i < interfaces.length ; i++ ) {
ret.add ( interfaces[i] );
}
return ret;
}
/**
* Private constructor: instances should be gotten through factory method.
*/
private ThreadLocalConnection ( NonXAPooledConnectionImp pooledConnection )
throws SQLException
{
useCount = 0;
this.wrapped = pooledConnection.getConnection ();
this.pooledConnection = pooledConnection;
setStale ( false );
resetForTransaction ();
updateInTransaction ();
}
private void resetForTransaction ()
{
setTransaction ( null );
participant = null;
}
private void setStale ( boolean val )
{
stale = val;
}
boolean isStale ()
{
return stale;
}
private void setTransaction ( CompositeTransaction val )
{
transaction = val;
}
private void updateInTransaction () throws SQLException
{
CompositeTransactionManager ctm = Configuration
.getCompositeTransactionManager ();
if ( ctm == null )
return;
CompositeTransaction ct = ctm.getCompositeTransaction ();
if ( ct != null && ct.getProperty ( TransactionManagerImp.JTA_PROPERTY_NAME ) != null ) {
// if we are already in another (parent) tx then reject this,
// because nested tx rollback can not be supported!!!
if ( isInTransaction () && !isInTransaction ( ct ) )
throw new SQLException (
"Connection accessed by transaction "
+ ct.getTid ()
+ " is already in use in another transaction: "
+ transaction.getTid ()
+ " Non-XA connections are not compatible with nested transaction use." );
setTransaction ( ct );
if ( participant == null ) {
// System.out.println ( "Adding participant");
// make sure we add a participant for commit/rollback
// notifications
participant = new NonXAParticipant ( this );
ct.addParticipant ( participant );
wrapped.setAutoCommit ( false );
}
} else {
// the current thread has NO tx, which means none was started (OK)
// or
// the previous one was terminated by the application. In that case,
// check that there was no ACTIVE rollback on timeout (meaning that
// transactionTerminated was never called!!!)
if ( isInTransaction () )
transactionTerminated ( false );
}
}
private boolean isInTransaction ()
{
return transaction != null;
}
private boolean isInTransaction ( CompositeTransaction ct )
{
boolean ret = false;
if ( isInTransaction () ) {
ret = transaction.isSameTransaction ( ct );
}
return ret;
}
private void decUseCount ()
{
useCount--;
checkReusability ();
}
private void checkReusability ()
{
if ( useCount == 0 && !isInTransaction () ) {
Configuration
.logDebug ( "ThreadLocalConnection: detected reusability" );
setStale ( true );
pooledConnection.notifyCloseListeners ();
} else {
Configuration.logDebug ( "ThreadLocalConnection: not reusable yet" );
}
}
void addHeuristicMessage ( HeuristicMessage msg )
{
if ( participant != null ) {
participant.addHeuristicMessage ( msg );
}
}
void incUseCount ()
{
useCount++;
}
void transactionTerminated ( boolean commit ) throws SQLException
{
// delegate commit or rollback to the underlying connection
try {
if ( commit ) {
Configuration.logInfo ( "ThreadLocalConnection: committing on connection...");
wrapped.commit ();
} else {
Configuration.logInfo ( "ThreadLocalConnection: rolling back on connection...");
wrapped.rollback ();
}
} catch ( SQLException e ) {
// make sure that reuse in pool is not possible
pooledConnection.setInvalidated ();
// e.printStackTrace();
throw e;
} finally {
// reset attributes for next tx
resetForTransaction ();
// put connection in pool if no longer used
checkReusability ();
}
}
/**
* @see java.lang.reflect.InvocationHandler#invoke(java.lang.Object,
* java.lang.reflect.Method, java.lang.Object[])
*/
public Object invoke ( Object o , Method m , Object[] args )
throws Throwable
{
if (NON_TRANSACTIONAL_METHOD_NAMES.contains(m.getName())) {
Configuration.logDebug ("Calling non-transactional method '" + m.getName() + "' on ThreadLocal connection, bypassing enlistment");
return m.invoke ( wrapped, args );
}
Object result = null;
// detect illegal use after connection was resubmitted to the pool
if ( isStale () )
throw new SQLException (
"Attempt to use connection after it was closed." );
// because connections can be gotten BEFORE a transaction is started,
// this is
// the place to check whether we are being used transactionally or not
updateInTransaction ();
if ( m.getName ().equals ( "close" ) ) {
decUseCount ();
} else if ( isInTransaction ()
&& (m.getName ().equals ( "rollback" ) || m.getName ().equals (
"commit" )) ) {
// transactional use forbids connection-level rollback or commit
throw new SQLException (
"Rollback or Commit not allowed inside a managed transaction!" );
} else {
// delegate to the underlying JDBC connection
try {
// System.out.println ( "Proxy: calling method" );
Configuration.logDebug ( "ThreadLocalConnection: delegating method " + m +
" to wrapped connection with args: " + args );
result = m.invoke ( wrapped, args );
} catch ( InvocationTargetException e ) {
throw e.getTargetException ();
} catch ( Exception e ) {
Configuration
.logDebug (
"ThreadLocalConnection: Unexpected invocation exception",
e );
throw new RuntimeException (
"Unexpected invocation exception: " + e.getMessage () );
}
}
return result;
}
public boolean usesConnection ( PooledConnection conn )
{
return pooledConnection.equals ( conn );
}
}