| /* |
| * 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.tephra; |
| |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.List; |
| |
| /** |
| * Utility class that provides handy methods for working with {@link TransactionAware} classes and their instances. |
| */ |
| public final class TransactionAwares { |
| private TransactionAwares() {} |
| |
| /** |
| * Create composite transaction aware object that delegates transaction logic to given collection of |
| * {@link TransactionAware}s |
| * @param transactionAwares collection of {@link TransactionAware}s |
| * @return instance of {@link TransactionAware} |
| */ |
| public static TransactionAware of(Collection<TransactionAware> transactionAwares) { |
| // this is most common case, trying to optimize |
| if (transactionAwares.size() == 1) { |
| return transactionAwares.iterator().next(); |
| } |
| |
| TransactionAwareCollection result = new TransactionAwareCollection(); |
| result.addAll(transactionAwares); |
| |
| return result; |
| } |
| |
| private static class TransactionAwareCollection extends ArrayList<TransactionAware> implements TransactionAware { |
| |
| @Override |
| public void startTx(Transaction tx) { |
| for (TransactionAware txAware : this) { |
| txAware.startTx(tx); |
| } |
| } |
| |
| @Override |
| public void updateTx(Transaction tx) { |
| for (TransactionAware txAware : this) { |
| txAware.updateTx(tx); |
| } |
| } |
| |
| @Override |
| public Collection<byte[]> getTxChanges() { |
| List<byte[]> changes = new ArrayList<byte[]>(); |
| for (TransactionAware txAware : this) { |
| changes.addAll(txAware.getTxChanges()); |
| } |
| |
| return changes; |
| } |
| |
| @Override |
| public boolean commitTx() throws Exception { |
| boolean success = true; |
| for (TransactionAware txAware : this) { |
| success = success && txAware.commitTx(); |
| } |
| return success; |
| } |
| |
| @Override |
| public void postTxCommit() { |
| for (TransactionAware txAware : this) { |
| txAware.postTxCommit(); |
| } |
| } |
| |
| @Override |
| public boolean rollbackTx() throws Exception { |
| boolean success = true; |
| for (TransactionAware txAware : this) { |
| success = success && txAware.rollbackTx(); |
| } |
| return success; |
| } |
| |
| @Override |
| public String getTransactionAwareName() { |
| // todo: will go away, see comment at TransactionAware |
| StringBuilder sb = new StringBuilder("{"); |
| for (TransactionAware txAware : this) { |
| sb.append(txAware.getTransactionAwareName()).append(","); |
| } |
| sb.replace(sb.length() - 1, sb.length() - 1, "}"); |
| return sb.toString(); |
| } |
| } |
| } |