| /** |
| * 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.jena.sparql.core; |
| |
| import org.apache.jena.query.ReadWrite; |
| import org.apache.jena.query.TxnType; |
| import org.apache.jena.sparql.JenaTransactionException; |
| |
| /** |
| * A null action {@link Transactional}. |
| * Does not protect anything but does track the transaction status. |
| * It does provide "abort". |
| */ |
| public class TransactionalNull implements Transactional { |
| |
| // Usage example: |
| private static class Example implements Transactional { |
| private final Transactional txn = new TransactionalNotSupported() ; |
| @Override public void begin() { txn.begin(); } |
| @Override public void begin(TxnType txnType) { txn.begin(txnType); } |
| @Override public void begin(ReadWrite mode) { txn.begin(mode); } |
| @Override public void commit() { txn.commit(); } |
| @Override public void abort() { txn.abort(); } |
| @Override public boolean promote(Promote mode) { return txn.promote(mode) ; } |
| @Override public boolean isInTransaction() { return txn.isInTransaction(); } |
| @Override public void end() { txn.end(); } |
| @Override public ReadWrite transactionMode() { return txn.transactionMode(); } |
| @Override public TxnType transactionType() { return txn.transactionType(); } |
| |
| // For DatasetGraphs: |
| // @Override public boolean supportsTransactions() { return true; } |
| // @Override public boolean supportsTransactionAbort() { return false; } |
| } |
| |
| public static Transactional create() { return new TransactionalNull(); } |
| |
| private ThreadLocal<Boolean> inTransaction = ThreadLocal.withInitial(() -> Boolean.FALSE); |
| private ThreadLocal<TxnType> txnType = ThreadLocal.withInitial(() -> null); |
| private ThreadLocal<ReadWrite> txnMode = ThreadLocal.withInitial(() -> null); |
| |
| @Override |
| public ReadWrite transactionMode() { |
| return txnMode.get(); |
| } |
| |
| @Override |
| public TxnType transactionType() { |
| return txnType.get(); |
| } |
| |
| @Override |
| public void begin(ReadWrite readWrite) { |
| begin(TxnType.convert(readWrite)); |
| } |
| |
| @Override |
| public void begin(TxnType type) { |
| if ( inTransaction.get() ) |
| throw new JenaTransactionException("Already in transaction"); |
| inTransaction.set(true); |
| txnType.set(type); |
| txnMode.set(TxnType.initial(type)); |
| } |
| |
| @Override |
| public boolean promote(Promote txnType) { |
| if ( ! inTransaction.get() ) |
| throw new JenaTransactionException("Not in transaction"); |
| txnMode.set(ReadWrite.WRITE); |
| return true; |
| } |
| |
| @Override |
| public void commit() { |
| if ( ! inTransaction.get() ) |
| throw new JenaTransactionException("Not in transaction"); |
| inTransaction.set(false); |
| } |
| |
| @Override |
| public void abort() { |
| if ( ! inTransaction.get() ) |
| throw new JenaTransactionException("Not in transaction"); |
| inTransaction.set(false); |
| } |
| |
| @Override |
| public boolean isInTransaction() { |
| return inTransaction.get(); |
| } |
| |
| @Override |
| public void end() { |
| clearup(); |
| } |
| |
| private void clearup() { |
| inTransaction.set(false); |
| inTransaction.remove(); |
| txnType.set(null); |
| txnType.remove(); |
| } |
| |
| public void remove() { |
| inTransaction.remove(); |
| } |
| } |