org.proton.plug.context.AbstractProtonContextSender.java Source code

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Here is the source code for org.proton.plug.context.AbstractProtonContextSender.java

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/**
 * 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.proton.plug.context;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.PooledByteBufAllocator;
import org.apache.qpid.proton.amqp.transport.SenderSettleMode;
import org.apache.qpid.proton.engine.Delivery;
import org.apache.qpid.proton.engine.Sender;
import org.apache.qpid.proton.message.ProtonJMessage;
import org.proton.plug.AMQPSessionCallback;
import org.proton.plug.exceptions.ActiveMQAMQPException;
import org.proton.plug.util.CreditsSemaphore;
import org.proton.plug.util.NettyWritable;

/**
 * A this is a wrapper around a ActiveMQ Artemis ServerConsumer for handling outgoing messages and incoming acks via a Proton Sender
 */
public abstract class AbstractProtonContextSender extends ProtonInitializable implements ProtonDeliveryHandler {
    protected final AbstractProtonSessionContext protonSession;
    protected final Sender sender;
    protected final AbstractConnectionContext connection;
    protected boolean closed = false;
    protected final AMQPSessionCallback sessionSPI;
    protected CreditsSemaphore creditsSemaphore = new CreditsSemaphore(0);

    public AbstractProtonContextSender(AbstractConnectionContext connection, Sender sender,
            AbstractProtonSessionContext protonSession, AMQPSessionCallback server) {
        this.connection = connection;
        this.sender = sender;
        this.protonSession = protonSession;
        this.sessionSPI = server;
    }

    public void onFlow(int credits) {
        this.creditsSemaphore.setCredits(credits);
    }

    /*
    * start the session
    * */
    public void start() throws ActiveMQAMQPException {
        sessionSPI.start();
        // protonSession.getServerSession().start();
    }

    /*
    * close the session
    * */
    public void close() throws ActiveMQAMQPException {
        closed = true;
        protonSession.removeSender(sender);
        synchronized (connection.getLock()) {
            sender.close();
        }

        connection.flush();
    }

    @Override
    /*
    * handle an incoming Ack from Proton, basically pass to ActiveMQ Artemis to handle
    * */
    public abstract void onMessage(Delivery delivery) throws ActiveMQAMQPException;

    /*
    * check the state of the consumer, i.e. are there any more messages. only really needed for browsers?
    * */
    public void checkState() {
    }

    public Sender getSender() {
        return sender;
    }

    protected int performSend(ProtonJMessage serverMessage, Object context) {
        if (!creditsSemaphore.tryAcquire()) {
            try {
                creditsSemaphore.acquire();
            } catch (InterruptedException e) {
                Thread.currentThread().interrupt();
                // nothing to be done here.. we just keep going
                throw new IllegalStateException(e.getMessage(), e);
            }
        }

        //presettle means we can ack the message on the dealer side before we send it, i.e. for browsers
        boolean preSettle = sender.getRemoteSenderSettleMode() == SenderSettleMode.SETTLED;

        //we only need a tag if we are going to ack later
        byte[] tag = preSettle ? new byte[0] : protonSession.getTag();

        ByteBuf nettyBuffer = PooledByteBufAllocator.DEFAULT.heapBuffer(1024);
        try {
            serverMessage.encode(new NettyWritable(nettyBuffer));

            int size = nettyBuffer.writerIndex();

            synchronized (connection.getLock()) {
                final Delivery delivery;
                delivery = sender.delivery(tag, 0, tag.length);
                delivery.setContext(context);

                // this will avoid a copy.. patch provided by Norman using buffer.array()
                sender.send(nettyBuffer.array(), nettyBuffer.arrayOffset() + nettyBuffer.readerIndex(),
                        nettyBuffer.readableBytes());

                if (preSettle) {
                    delivery.settle();
                } else {
                    sender.advance();
                }
            }

            connection.flush();

            return size;
        } finally {
            nettyBuffer.release();
        }
    }
}