2 * ============LICENSE_START=======================================================
4 * ================================================================================
5 * Copyright (C) 2017-2018 AT&T Intellectual Property. All rights reserved.
6 * ================================================================================
7 * Copyright (C) 2017 Amdocs
8 * =============================================================================
9 * Licensed under the Apache License, Version 2.0 (the "License");
10 * you may not use this file except in compliance with the License.
11 * You may obtain a copy of the License at
13 * http://www.apache.org/licenses/LICENSE-2.0
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21 * ============LICENSE_END=========================================================
24 package org.onap.appc.listener;
27 * This interface defines a listener that subscribes to a DMaaP topic and continually polls for messages. The
28 * listener does all operations in the run() method and long running operations should be created in a separate worker
32 public interface Listener extends Runnable {
35 * Should start a continuous poll to get messages from the message bus only ending when stop() or stopNow() are
38 * @see java.lang.Runnable#run()
44 * Signals the listener to stop accepting new messages to the queue and to cleanly finish processing all remaining
45 * messages in the queue. This can take a significant amount of time to complete depending on the thread pool
46 * characteristics. Similar to {@link #stopNow()}
51 * Signals the listener to stop accepting new messages to the queue and to destroy all remaining messages in the
52 * queue. This will complete quicker than {@link #stop()} at the cost of discarded requests. Recovery of these
53 * requests would have to be caught downstream. Similar to {@link #stop()}
55 public void stopNow();
58 * @return A string that shows various benchmarking data. Can be used by humans to tune the thread pool.
60 public String getBenchmark();
63 * @return The listener's id when requesting messages from DMaaP. Also known as the group id.
65 public String getListenerId();
68 * Sets the listener's id to use when requesting messages from DMaaP. Also known as the group id.
73 public void setListenerId(String idString);