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#ifndef QPID_CLIENT_LOCALQUEUEIMPL_H
#define QPID_CLIENT_LOCALQUEUEIMPL_H
/*
*
* 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.
*
*/
#include "qpid/client/ClientImportExport.h"
#include "qpid/client/Handle.h"
#include "qpid/client/Message.h"
#include "qpid/client/Subscription.h"
#include "qpid/client/Demux.h"
#include "qpid/sys/Time.h"
#include "qpid/RefCounted.h"
namespace qpid {
namespace client {
/**
* A local queue to collect messages retrieved from a remote broker
* queue. Create a queue and subscribe it using the SubscriptionManager.
* Messages from the remote queue on the broker will be stored in the
* local queue until you retrieve them.
*
* \ingroup clientapi
*
* \details Using a Local Queue
*
* <pre>
* LocalQueue local_queue;
* subscriptions.subscribe(local_queue, string("message_queue"));
* for (int i=0; i<10; i++) {
* Message message = local_queue.get();
* std::cout << message.getData() << std::endl;
* }
* </pre>
*
* <h2>Getting Messages</h2>
*
* <ul><li>
* <p>get()</p>
* <pre>Message message = local_queue.get();</pre>
* <pre>// Specifying timeouts (TIME_SEC, TIME_MSEC, TIME_USEC, TIME_NSEC)
*#include <qpid/sys/Time.h>
*Message message;
*local_queue.get(message, 5*sys::TIME_SEC);</pre></li></ul>
*
* <h2>Checking size</h2>
* <ul><li>
* <p>empty()</p>
* <pre>if (local_queue.empty()) { ... }</pre></li>
* <li><p>size()</p>
* <pre>std::cout << local_queue.size();</pre></li>
* </ul>
*/
class LocalQueueImpl : public RefCounted {
public:
/** Wait up to timeout for the next message from the local queue.
*@param result Set to the message from the queue.
*@param timeout wait up this timeout for a message to appear.
*@return true if result was set, false if queue was empty after timeout.
*/
bool get(Message& result, sys::Duration timeout=0);
/** Get the next message off the local queue, or wait up to the timeout
* for message from the broker queue.
*@param timeout wait up this timeout for a message to appear.
*@return message from the queue.
*@throw ClosedException if subscription is closed or timeout exceeded.
*/
Message get(sys::Duration timeout=sys::TIME_INFINITE);
/** Synonym for get() */
Message pop(sys::Duration timeout=sys::TIME_INFINITE);
/** Return true if local queue is empty. */
bool empty() const;
/** Number of messages on the local queue */
size_t size() const;
private:
Demux::QueuePtr queue;
Subscription subscription;
friend class SubscriptionManagerImpl;
};
}} // namespace qpid::client
#endif /*!QPID_CLIENT_LOCALQUEUEIMPL_H*/
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