001/*
002 *  Copyright (c) 2022-2023, Mybatis-Flex (fuhai999@gmail.com).
003 *  <p>
004 *  Licensed under the Apache License, Version 2.0 (the "License");
005 *  you may not use this file except in compliance with the License.
006 *  You may obtain a copy of the License at
007 *  <p>
008 *  http://www.apache.org/licenses/LICENSE-2.0
009 *  <p>
010 *  Unless required by applicable law or agreed to in writing, software
011 *  distributed under the License is distributed on an "AS IS" BASIS,
012 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 *  See the License for the specific language governing permissions and
014 *  limitations under the License.
015 */
016package com.mybatisflex.spring;
017
018import com.mybatisflex.core.transaction.TransactionContext;
019import com.mybatisflex.core.transaction.TransactionalManager;
020import com.mybatisflex.core.util.StringUtil;
021import org.springframework.jdbc.datasource.JdbcTransactionObjectSupport;
022import org.springframework.transaction.TransactionDefinition;
023import org.springframework.transaction.TransactionException;
024import org.springframework.transaction.support.AbstractPlatformTransactionManager;
025import org.springframework.transaction.support.DefaultTransactionStatus;
026
027/**
028 * MyBatis-Flex 事务支持。
029 *
030 * @author michael
031 */
032public class FlexTransactionManager extends AbstractPlatformTransactionManager {
033
034    @Override
035    protected Object doGetTransaction() throws TransactionException {
036        return new TransactionObject(TransactionContext.getXID());
037    }
038
039    @Override
040    protected boolean isExistingTransaction(Object transaction) throws TransactionException {
041        TransactionObject transactionObject = (TransactionObject) transaction;
042        return StringUtil.isNotBlank(transactionObject.prevXid);
043    }
044
045    @Override
046    protected Object doSuspend(Object transaction) throws TransactionException {
047        TransactionContext.release();
048        TransactionObject transactionObject = (TransactionObject) transaction;
049        return transactionObject.prevXid;
050    }
051
052    @Override
053    protected void doResume(Object transaction, Object suspendedResources) throws TransactionException {
054        String xid = (String) suspendedResources;
055        TransactionContext.holdXID(xid);
056    }
057
058    @Override
059    protected void doBegin(Object transaction, TransactionDefinition definition) throws TransactionException {
060        TransactionObject transactionObject = (TransactionObject) transaction;
061        transactionObject.currentXid = TransactionalManager.startTransactional();
062    }
063
064    @Override
065    protected void doCommit(DefaultTransactionStatus status) throws TransactionException {
066        TransactionObject transactionObject = (TransactionObject) status.getTransaction();
067        TransactionalManager.commit(transactionObject.currentXid);
068        transactionObject.clear();
069    }
070
071    @Override
072    protected void doRollback(DefaultTransactionStatus status) throws TransactionException {
073        TransactionObject transactionObject = (TransactionObject) status.getTransaction();
074        TransactionalManager.rollback(transactionObject.currentXid);
075        transactionObject.clear();
076    }
077
078    @Override
079    protected void doSetRollbackOnly(DefaultTransactionStatus status) throws TransactionException {
080        // 在多个事务嵌套时，子事务的传递方式为 REQUIRED（加入当前事务）
081        // 那么，当子事务抛出异常时，会调当前方法，而不是直接调用 doRollback
082        // 此时，需要标识 prevXid 进行 Rollback
083        TransactionObject transactionObject = (TransactionObject) status.getTransaction();
084        transactionObject.setRollbackOnly();
085    }
086
087
088    static class TransactionObject extends JdbcTransactionObjectSupport {
089
090        private static final ThreadLocal<String> ROLLBACK_ONLY_XIDS = new ThreadLocal<>();
091
092        private final String prevXid;
093        private String currentXid;
094
095        public TransactionObject(String prevXid) {
096            this.prevXid = prevXid;
097        }
098
099        public void setRollbackOnly() {
100            ROLLBACK_ONLY_XIDS.set(prevXid);
101        }
102
103        public void clear() {
104            ROLLBACK_ONLY_XIDS.remove();
105        }
106
107        @Override
108        public boolean isRollbackOnly() {
109            return currentXid != null && currentXid.equals(ROLLBACK_ONLY_XIDS.get());
110        }
111    }
112
113}