2 * Sonitus - ExternalFilter.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.EOFException;
21 import java.io.IOException;
22 import java.io.InputStream;
23 import java.io.OutputStream;
24 import java.io.PipedInputStream;
25 import java.io.PipedOutputStream;
26 import java.util.Arrays;
27 import java.util.logging.Logger;
29 import net.pterodactylus.sonitus.data.ConnectException;
30 import net.pterodactylus.sonitus.data.Connection;
31 import net.pterodactylus.sonitus.data.Filter;
32 import net.pterodactylus.sonitus.data.Format;
33 import net.pterodactylus.sonitus.data.Source;
34 import net.pterodactylus.sonitus.io.InputStreamDrainer;
36 import com.google.common.base.Preconditions;
37 import com.google.common.collect.ImmutableList;
38 import com.google.common.collect.Iterables;
39 import com.google.common.io.ByteStreams;
42 * {@link Filter} implementation that runs its {@link Source} through an
45 * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
47 public abstract class ExternalFilter implements Filter {
50 private final Logger logger = Logger.getLogger(getClass().getName());
52 /** The format of the source. */
53 private Format format;
55 /** The input stream that will hold the converted source. */
56 private PipedInputStream pipedInputStream;
62 public Format format() {
67 public byte[] get(int bufferSize) throws EOFException, IOException {
68 byte[] buffer = new byte[bufferSize];
69 int read = pipedInputStream.read(buffer);
70 return Arrays.copyOf(buffer, read);
74 public void connect(Source source) throws ConnectException {
75 Preconditions.checkNotNull(source, "source must not be null");
77 format = source.format();
79 final Process process = Runtime.getRuntime().exec(Iterables.toArray(ImmutableList.<String>builder().add(binary(format)).addAll(parameters(format)).build(), String.class));
80 final InputStream processOutput = process.getInputStream();
81 final OutputStream processInput = process.getOutputStream();
82 final InputStream processError = process.getErrorStream();
83 final PipedOutputStream pipedOutputStream = new PipedOutputStream();
84 pipedInputStream = new PipedInputStream(pipedOutputStream);
85 new Thread(new InputStreamDrainer(processError)).start();
86 new Thread(new Runnable() {
91 ByteStreams.copy(processOutput, pipedOutputStream);
92 } catch (IOException ioe1) {
93 /* okay, just exit. */
95 logger.finest("Reading stdout finished.");
98 new Thread(new Connection(source) {
101 protected int bufferSize() {
106 protected void feed(byte[] buffer) throws IOException {
107 processInput.write(buffer);
108 processInput.flush();
112 protected void finish() throws IOException {
113 processInput.close();
114 processOutput.close();
115 processError.close();
118 } catch (IOException ioe1) {
128 * Returns the location of the binary to execute.
131 * The format being processed
132 * @return The location of the binary to execute
134 protected abstract String binary(Format format);
137 * Returns the parameters for the binary.
140 * The format being processed
141 * @return The parameters for the binary
143 protected abstract Iterable<String> parameters(Format format);