2 * Sonitus - DelayFilter.java - Copyright © 2013 David Roden
4 * This program is free software: you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation, either version 3 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 package net.pterodactylus.sonitus.data.filter;
20 import java.io.IOException;
21 import java.util.logging.Logger;
23 import net.pterodactylus.sonitus.data.Metadata;
25 import com.google.common.eventbus.EventBus;
28 * Rate limiting filter that only passes a specified amount of data per second
29 * from its {@link net.pterodactylus.sonitus.data.Source} to its {@link
30 * net.pterodactylus.sonitus.data.Sink}.
32 * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
34 public class RateLimitingFilter extends DummyFilter {
37 private static final Logger logger = Logger.getLogger(RateLimitingFilter.class.getName());
39 /** The limiting rate in bytes/second. */
40 private final int rate;
42 /** The start time. */
43 private long startTime;
45 /** The number of bytes. */
49 * Creates a new rate limiting filter.
54 * The name of the filter
56 * The limiting rate (in bytes/second)
58 public RateLimitingFilter(EventBus eventBus, String name, int rate) {
59 this(eventBus, name, rate, 0);
63 * Creates a new rate limiting filter.
68 * The name of the filter
70 * The limiting rate (in bytes/second)
71 * @param fastStartTime
72 * The amount of time at the start of the filtering during which no delay
73 * will occur (in milliseconds)
75 public RateLimitingFilter(EventBus eventBus, String name, int rate, long fastStartTime) {
76 super(eventBus, name);
78 this.counter = (long) (-rate * (fastStartTime / 1000.0));
86 public void open(Metadata metadata) throws IOException {
88 startTime = System.currentTimeMillis();
92 public void process(byte[] buffer) throws IOException {
93 super.process(buffer);
95 counter += buffer.length;
96 long waitTime = (long) (counter / (rate / 1000.0));
97 while ((System.currentTimeMillis() - startTime) < waitTime) {
99 long limitDelay = waitTime - (System.currentTimeMillis() - startTime);
100 logger.finest(String.format("Waiting %d ms...", limitDelay));
101 Thread.sleep(limitDelay);
102 } catch (InterruptedException ie1) {
103 /* ignore, keep looping. */
106 logger.finest(String.format("Processed %d Bytes during %d ms, that’s %.1f bytes/s.", counter, System.currentTimeMillis() - startTime, counter / ((System.currentTimeMillis() - startTime) / 1000.0)));