Java tutorial
/* * #%L * Alfresco Repository * %% * Copyright (C) 2005 - 2016 Alfresco Software Limited * %% * This file is part of the Alfresco software. * If the software was purchased under a paid Alfresco license, the terms of * the paid license agreement will prevail. Otherwise, the software is * provided under the following open source license terms: * * Alfresco 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 3 of the License, or * (at your option) any later version. * * Alfresco 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 Alfresco. If not, see <http://www.gnu.org/licenses/>. * #L% */ package org.alfresco.repo.transaction; import javax.transaction.RollbackException; import javax.transaction.Status; import javax.transaction.UserTransaction; import org.alfresco.error.AlfrescoRuntimeException; import org.alfresco.service.transaction.TransactionService; import org.springframework.extensions.surf.util.ParameterCheck; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * Class containing transactions helper methods and interfaces. * * @deprecated Use a {@link RetryingTransactionHelper} instance * * @author Derek Hulley */ public class TransactionUtil { private static Log logger = LogFactory.getLog(TransactionUtil.class); /** * Transaction work interface. * <p> * This interface encapsulates a unit of work that should be done within a * transaction. * * @deprecated * @see RetryingTransactionHelper.RetryingTransactionCallback */ public interface TransactionWork<Result> { /** * Method containing the work to be done in the user transaction. * * @return Return the result of the operation */ Result doWork() throws Throwable; } /** * Flush transaction. */ public static void flush() { AlfrescoTransactionSupport.flush(); } /** * Execute the transaction work in a user transaction * * @param transactionService the transaction service * @param transactionWork the transaction work * * @throws java.lang.RuntimeException if the transaction was rolled back * * @deprecated Use a {@link RetryingTransactionHelper} instance */ public static <R> R executeInUserTransaction(TransactionService transactionService, TransactionWork<R> transactionWork) { return executeInTransaction(transactionService, transactionWork, false, false); } /** * Execute the transaction work in a user transaction. * Any current transaction will be continued. * * @param transactionService the transaction service * @param transactionWork the transaction work * @param readOnly true if the transaction should be read-only * * @throws java.lang.RuntimeException if the transaction was rolled back * * @deprecated Use a {@link RetryingTransactionHelper} instance */ public static <R> R executeInUserTransaction(TransactionService transactionService, TransactionWork<R> transactionWork, boolean readOnly) { return executeInTransaction(transactionService, transactionWork, false, readOnly); } /** * Execute the transaction work in a <b>writable</b>, non-propagating user transaction. * Any current transaction will be suspended a new one started. * * @param transactionService the transaction service * @param transactionWork the transaction work * * @throws java.lang.RuntimeException if the transaction was rolled back * * @deprecated Use a {@link RetryingTransactionHelper} instance */ public static <R> R executeInNonPropagatingUserTransaction(TransactionService transactionService, TransactionWork<R> transactionWork) { return executeInTransaction(transactionService, transactionWork, true, false); } /** * Execute the transaction work in a non-propagating user transaction. * Any current transaction will be suspended a new one started. * * @param transactionService the transaction service * @param transactionWork the transaction work * @param readOnly true if the transaction should be read-only * * @throws java.lang.RuntimeException if the transaction was rolled back * * @deprecated Use a {@link RetryingTransactionHelper} instance */ public static <R> R executeInNonPropagatingUserTransaction(TransactionService transactionService, TransactionWork<R> transactionWork, boolean readOnly) { return executeInTransaction(transactionService, transactionWork, true, readOnly); } /** * Execute the transaction work in a user transaction of a specified type * * @param transactionService the transaction service * @param transactionWork the transaction work * @param nonPropagatingUserTransaction indicates whether the transaction * should be non propigating or not * @param readOnly true if the transaction should be read-only * * @throws java.lang.RuntimeException if the transaction was rolled back */ private static <R> R executeInTransaction(TransactionService transactionService, TransactionWork<R> transactionWork, boolean nonPropagatingUserTransaction, boolean readOnly) { ParameterCheck.mandatory("transactionWork", transactionWork); R result = null; // Get the right type of user transaction UserTransaction txn = null; if (nonPropagatingUserTransaction == true) { txn = transactionService.getNonPropagatingUserTransaction(); } else { txn = transactionService.getUserTransaction(readOnly); } try { // Begin the transaction, do the work and then commit the // transaction txn.begin(); result = transactionWork.doWork(); // rollback or commit if (txn.getStatus() == Status.STATUS_MARKED_ROLLBACK) { // something caused the transaction to be marked for rollback txn.rollback(); } else { // transaction should still commit txn.commit(); } } catch (RollbackException exception) { // commit failed throw new AlfrescoRuntimeException("Unexpected rollback exception: \n" + exception.getMessage(), exception); } catch (Throwable exception) { try { // Roll back the exception txn.rollback(); } catch (Throwable rollbackException) { // just dump the exception - we are already in a failure state logger.error("Error rolling back transaction", rollbackException); } // Re-throw the exception if (exception instanceof RuntimeException) { throw (RuntimeException) exception; } else { throw new RuntimeException("Error during execution of transaction.", exception); } } return result; } }