Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * 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. See the License for the * specific language governing permissions and limitations * under the License. */ package org.apache.ranger.service; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Qualifier; import org.springframework.stereotype.Service; import org.springframework.transaction.PlatformTransactionManager; import org.springframework.transaction.TransactionDefinition; import org.springframework.transaction.TransactionStatus; import org.springframework.transaction.support.TransactionCallback; import org.springframework.transaction.support.TransactionTemplate; import javax.annotation.PostConstruct; import javax.annotation.PreDestroy; import java.util.concurrent.Executors; import java.util.concurrent.ScheduledExecutorService; import java.util.concurrent.TimeUnit; import static java.util.concurrent.TimeUnit.MILLISECONDS; @Service public class RangerTransactionService { @Autowired @Qualifier(value = "transactionManager") PlatformTransactionManager txManager; private static final Log LOG = LogFactory.getLog(RangerTransactionService.class); private ScheduledExecutorService scheduler = null; @PostConstruct public void init() { scheduler = Executors.newScheduledThreadPool(1); } @PreDestroy public void destroy() { try { LOG.info("attempt to shutdown RangerTransactionService"); scheduler.shutdown(); scheduler.awaitTermination(5, TimeUnit.SECONDS); } catch (InterruptedException e) { LOG.error("RangerTransactionService tasks interrupted"); } finally { if (!scheduler.isTerminated()) { LOG.info("cancel non-finished RangerTransactionService tasks"); } scheduler.shutdownNow(); LOG.info("RangerTransactionService shutdown finished"); } } public void executeAfterTransactionComplete(final Runnable task) { try { scheduler.schedule(new Runnable() { @Override public void run() { if (task != null) { try { //Create new transaction TransactionTemplate txTemplate = new TransactionTemplate(txManager); txTemplate.setPropagationBehavior(TransactionDefinition.PROPAGATION_REQUIRES_NEW); txTemplate.execute(new TransactionCallback<Object>() { public Object doInTransaction(TransactionStatus status) { task.run(); return null; } }); } catch (Exception e) { LOG.error("Failed to commit TransactionService transaction", e); LOG.error("Ignoring..."); } } } }, 1000L, MILLISECONDS); } catch (Exception e) { LOG.error("Failed to schedule TransactionService transaction:", e); LOG.error("Ignroing..."); } } }