/*
* JBoss, Home of Professional Open Source.
* Copyright 2008, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.as.test.integration.ejb.transaction.bmt.lazyenlist;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.annotation.Resource;
import javax.ejb.Stateless;
import javax.ejb.TransactionManagement;
import javax.ejb.TransactionManagementType;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.sql.DataSource;
import javax.transaction.NotSupportedException;
import javax.transaction.Status;
import javax.transaction.SystemException;
import javax.transaction.UserTransaction;
/**
* @author <a href="mailto:cdewolf@redhat.com">Carlo de Wolf</a>
*/
@Stateless
@TransactionManagement(TransactionManagementType.BEAN)
public class ATMBean implements ATM {
@PersistenceContext
private EntityManager em;
@Resource
private UserTransaction ut;
@Resource(mappedName = "java:jboss/datasources/ExampleDS")
private DataSource ds;
private void beginTx() {
try {
ut.begin();
} catch (NotSupportedException e) {
throw new RuntimeException(e);
} catch (SystemException e) {
throw new RuntimeException(e);
}
}
private void commitTx() {
try {
ut.commit();
} catch (RuntimeException e) {
throw e;
}
// RollbackException, HeuristicMixedException, HeuristicRollbackException, SystemException
catch (Exception e) {
throw new RuntimeException(e);
}
}
public long createAccount(double balance) {
beginTx();
try {
Account a = new Account();
a.setBalance(balance);
em.persist(a);
commitTx();
return a.getId();
} finally {
rollbackTxIfNeeded();
}
}
public double getBalance(long id) {
Account a = em.find(Account.class, id);
return a.getBalance();
}
private void rollbackTx() {
try {
ut.rollback();
} catch (RuntimeException e) {
throw e;
}
// SecurityException, SystemException
catch (Exception e) {
throw new RuntimeException(e);
}
}
private void rollbackTxIfNeeded() {
try {
switch (ut.getStatus()) {
case Status.STATUS_COMMITTED:
case Status.STATUS_NO_TRANSACTION:
break;
default:
ut.rollback();
}
} catch (RuntimeException e) {
throw e;
}
// SecurityException, SystemException
catch (Exception e) {
throw new RuntimeException(e);
}
}
public double depositTwiceWithRollback(long id, double a1, double a2) {
Account a;
beginTx();
try {
a = em.find(Account.class, id);
// unsafe (nolock)
a.setBalance(a.getBalance() + a1);
em.flush();
commitTx();
} finally {
rollbackTxIfNeeded();
}
beginTx();
try {
// unsafe
a.setBalance(a.getBalance() + a2);
em.flush();
} finally {
rollbackTx();
}
return a.getBalance();
}
/**
* Do the same, but then raw sql.
*
* @param id
* @param a1
* @param a2
*/
public double withdrawTwiceWithRollback(long id, double a1, double a2) {
try {
Connection conn = ds.getConnection();
PreparedStatement psSelect = conn.prepareStatement("SELECT balance FROM account WHERE id = ?");
double balance;
try {
psSelect.setLong(1, id);
ResultSet rs = psSelect.executeQuery();
if (!rs.next())
throw new IllegalArgumentException("can't find account " + id);
balance = rs.getDouble(1);
rs.close();
psSelect.close();
PreparedStatement ps = conn.prepareStatement("UPDATE account SET balance = ? WHERE id = ?");
try {
beginTx();
try {
balance -= a1;
ps.setDouble(1, balance);
ps.setLong(2, id);
int rows = ps.executeUpdate();
if (rows != 1)
throw new IllegalStateException("first update failed");
ps.close();
conn.close();
commitTx();
} finally {
rollbackTxIfNeeded();
}
conn = ds.getConnection();
ps = conn.prepareStatement("UPDATE account SET balance = ? WHERE id = ?");
beginTx();
try {
balance -= a2;
ps.setDouble(1, balance);
ps.setLong(2, id);
int rows = ps.executeUpdate();
if (rows != 1)
throw new IllegalStateException("second update failed");
} finally {
rollbackTx();
}
} finally {
ps.close();
}
return balance;
} finally {
conn.close();
}
} catch (SQLException e) {
throw new RuntimeException(e);
}
}
}