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ActiveMQ example source code file (JournalTransactionStore.java)

This example ActiveMQ source code file (JournalTransactionStore.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - ActiveMQ tags/keywords

arraylist, arraylist, io, ioexception, ioexception, iterator, linkedhashmap, message, messageack, object, recordlocation, recordlocation, tx, tx, txoperation, util

The ActiveMQ JournalTransactionStore.java source code

/**
 * 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.activemq.store.journal;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import javax.transaction.xa.XAException;
import org.apache.activeio.journal.RecordLocation;
import org.apache.activemq.command.JournalTopicAck;
import org.apache.activemq.command.JournalTransaction;
import org.apache.activemq.command.Message;
import org.apache.activemq.command.MessageAck;
import org.apache.activemq.command.TransactionId;
import org.apache.activemq.command.XATransactionId;
import org.apache.activemq.store.TransactionRecoveryListener;
import org.apache.activemq.store.TransactionStore;

/**
 */
public class JournalTransactionStore implements TransactionStore {

    private final JournalPersistenceAdapter peristenceAdapter;
    private final Map<Object, Tx> inflightTransactions = new LinkedHashMap();
    private final Map<TransactionId, Tx> preparedTransactions = new LinkedHashMap();
    private boolean doingRecover;

    public static class TxOperation {

        static final byte ADD_OPERATION_TYPE = 0;
        static final byte REMOVE_OPERATION_TYPE = 1;
        static final byte ACK_OPERATION_TYPE = 3;

        public byte operationType;
        public JournalMessageStore store;
        public Object data;

        public TxOperation(byte operationType, JournalMessageStore store, Object data) {
            this.operationType = operationType;
            this.store = store;
            this.data = data;
        }

    }

    /**
     * Operations
     * 
     * 
     */
    public static class Tx {

        private final RecordLocation location;
        private final ArrayList<TxOperation> operations = new ArrayList();

        public Tx(RecordLocation location) {
            this.location = location;
        }

        public void add(JournalMessageStore store, Message msg) {
            operations.add(new TxOperation(TxOperation.ADD_OPERATION_TYPE, store, msg));
        }

        public void add(JournalMessageStore store, MessageAck ack) {
            operations.add(new TxOperation(TxOperation.REMOVE_OPERATION_TYPE, store, ack));
        }

        public void add(JournalTopicMessageStore store, JournalTopicAck ack) {
            operations.add(new TxOperation(TxOperation.ACK_OPERATION_TYPE, store, ack));
        }

        public Message[] getMessages() {
            ArrayList<Object> list = new ArrayList();
            for (Iterator<TxOperation> iter = operations.iterator(); iter.hasNext();) {
                TxOperation op = iter.next();
                if (op.operationType == TxOperation.ADD_OPERATION_TYPE) {
                    list.add(op.data);
                }
            }
            Message rc[] = new Message[list.size()];
            list.toArray(rc);
            return rc;
        }

        public MessageAck[] getAcks() {
            ArrayList<Object> list = new ArrayList();
            for (Iterator<TxOperation> iter = operations.iterator(); iter.hasNext();) {
                TxOperation op = iter.next();
                if (op.operationType == TxOperation.REMOVE_OPERATION_TYPE) {
                    list.add(op.data);
                }
            }
            MessageAck rc[] = new MessageAck[list.size()];
            list.toArray(rc);
            return rc;
        }

        public ArrayList<TxOperation> getOperations() {
            return operations;
        }

    }

    public JournalTransactionStore(JournalPersistenceAdapter adapter) {
        this.peristenceAdapter = adapter;
    }

    /**
     * @throws IOException
     * @see org.apache.activemq.store.TransactionStore#prepare(TransactionId)
     */
    public void prepare(TransactionId txid) throws IOException {
        Tx tx = null;
        synchronized (inflightTransactions) {
            tx = inflightTransactions.remove(txid);
        }
        if (tx == null) {
            return;
        }
        peristenceAdapter.writeCommand(new JournalTransaction(JournalTransaction.XA_PREPARE, txid, false),
                                       true);
        synchronized (preparedTransactions) {
            preparedTransactions.put(txid, tx);
        }
    }

    /**
     * @throws IOException
     * @see org.apache.activemq.store.TransactionStore#prepare(TransactionId)
     */
    public void replayPrepare(TransactionId txid) throws IOException {
        Tx tx = null;
        synchronized (inflightTransactions) {
            tx = inflightTransactions.remove(txid);
        }
        if (tx == null) {
            return;
        }
        synchronized (preparedTransactions) {
            preparedTransactions.put(txid, tx);
        }
    }

    public Tx getTx(Object txid, RecordLocation location) {
        Tx tx = null;
        synchronized (inflightTransactions) {
            tx = inflightTransactions.get(txid);
        }
        if (tx == null) {
            tx = new Tx(location);
            inflightTransactions.put(txid, tx);
        }
        return tx;
    }

    /**
     * @throws XAException
     * @see org.apache.activemq.store.TransactionStore#commit(org.apache.activemq.service.Transaction)
     */
    public void commit(TransactionId txid, boolean wasPrepared, Runnable preCommit,Runnable postCommit) throws IOException {
        Tx tx;
        if (preCommit != null) {
            preCommit.run();
        }
        if (wasPrepared) {
            synchronized (preparedTransactions) {
                tx = preparedTransactions.remove(txid);
            }
        } else {
            synchronized (inflightTransactions) {
                tx = inflightTransactions.remove(txid);
            }
        }
        if (tx == null) {
            if (postCommit != null) {
                postCommit.run();
            }
            return;
        }
        if (txid.isXATransaction()) {
            peristenceAdapter.writeCommand(new JournalTransaction(JournalTransaction.XA_COMMIT, txid,
                                                                  wasPrepared), true);
        } else {
            peristenceAdapter.writeCommand(new JournalTransaction(JournalTransaction.LOCAL_COMMIT, txid,
                                                                  wasPrepared), true);
        }
        if (postCommit != null) {
            postCommit.run();
        }
    }

    /**
     * @throws XAException
     * @see org.apache.activemq.store.TransactionStore#commit(org.apache.activemq.service.Transaction)
     */
    public Tx replayCommit(TransactionId txid, boolean wasPrepared) throws IOException {
        if (wasPrepared) {
            synchronized (preparedTransactions) {
                return preparedTransactions.remove(txid);
            }
        } else {
            synchronized (inflightTransactions) {
                return inflightTransactions.remove(txid);
            }
        }
    }

    /**
     * @throws IOException
     * @see org.apache.activemq.store.TransactionStore#rollback(TransactionId)
     */
    public void rollback(TransactionId txid) throws IOException {
        Tx tx = null;
        synchronized (inflightTransactions) {
            tx = inflightTransactions.remove(txid);
        }
        if (tx != null) {
            synchronized (preparedTransactions) {
                tx = preparedTransactions.remove(txid);
            }
        }
        if (tx != null) {
            if (txid.isXATransaction()) {
                peristenceAdapter.writeCommand(new JournalTransaction(JournalTransaction.XA_ROLLBACK, txid,
                                                                      false), true);
            } else {
                peristenceAdapter.writeCommand(new JournalTransaction(JournalTransaction.LOCAL_ROLLBACK,
                                                                      txid, false), true);
            }
        }
    }

    /**
     * @throws IOException
     * @see org.apache.activemq.store.TransactionStore#rollback(TransactionId)
     */
    public void replayRollback(TransactionId txid) throws IOException {
        boolean inflight = false;
        synchronized (inflightTransactions) {
            inflight = inflightTransactions.remove(txid) != null;
        }
        if (inflight) {
            synchronized (preparedTransactions) {
                preparedTransactions.remove(txid);
            }
        }
    }

    public void start() throws Exception {
    }

    public void stop() throws Exception {
    }

    public synchronized void recover(TransactionRecoveryListener listener) throws IOException {
        // All the in-flight transactions get rolled back..
        synchronized (inflightTransactions) {
            inflightTransactions.clear();
        }
        this.doingRecover = true;
        try {
            Map<TransactionId, Tx> txs = null;
            synchronized (preparedTransactions) {
                txs = new LinkedHashMap<TransactionId, Tx>(preparedTransactions);
            }
            for (Iterator<TransactionId> iter = txs.keySet().iterator(); iter.hasNext();) {
                Object txid = iter.next();
                Tx tx = txs.get(txid);
                listener.recover((XATransactionId)txid, tx.getMessages(), tx.getAcks());
            }
        } finally {
            this.doingRecover = false;
        }
    }

    /**
     * @param message
     * @throws IOException
     */
    void addMessage(JournalMessageStore store, Message message, RecordLocation location) throws IOException {
        Tx tx = getTx(message.getTransactionId(), location);
        tx.add(store, message);
    }

    /**
     * @param ack
     * @throws IOException
     */
    public void removeMessage(JournalMessageStore store, MessageAck ack, RecordLocation location)
        throws IOException {
        Tx tx = getTx(ack.getTransactionId(), location);
        tx.add(store, ack);
    }

    public void acknowledge(JournalTopicMessageStore store, JournalTopicAck ack, RecordLocation location) {
        Tx tx = getTx(ack.getTransactionId(), location);
        tx.add(store, ack);
    }

    public RecordLocation checkpoint() throws IOException {
        // Nothing really to checkpoint.. since, we don't
        // checkpoint tx operations in to long term store until they are
        // committed.
        // But we keep track of the first location of an operation
        // that was associated with an active tx. The journal can not
        // roll over active tx records.
        RecordLocation rc = null;
        synchronized (inflightTransactions) {
            for (Iterator<Tx> iter = inflightTransactions.values().iterator(); iter.hasNext();) {
                Tx tx = iter.next();
                RecordLocation location = tx.location;
                if (rc == null || rc.compareTo(location) < 0) {
                    rc = location;
                }
            }
        }
        synchronized (preparedTransactions) {
            for (Iterator<Tx> iter = preparedTransactions.values().iterator(); iter.hasNext();) {
                Tx tx = iter.next();
                RecordLocation location = tx.location;
                if (rc == null || rc.compareTo(location) < 0) {
                    rc = location;
                }
            }
            return rc;
        }
    }

    public boolean isDoingRecover() {
        return doingRecover;
    }

}

Other ActiveMQ examples (source code examples)

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