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.Metadata;
34 import net.pterodactylus.sonitus.data.Source;
35 import net.pterodactylus.sonitus.io.InputStreamDrainer;
37 import com.google.common.base.Preconditions;
38 import com.google.common.collect.ImmutableList;
39 import com.google.common.collect.Iterables;
40 import com.google.common.io.ByteStreams;
43 * {@link Filter} implementation that runs its {@link Source} through an
46 * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
48 public abstract class ExternalFilter implements Filter {
51 private final Logger logger = Logger.getLogger(getClass().getName());
54 private Source source;
56 /** The input stream that will hold the converted source. */
57 private PipedInputStream pipedInputStream;
64 public Format format() {
65 return source.format();
69 public Metadata metadata() {
70 return source.metadata();
74 public byte[] get(int bufferSize) throws EOFException, IOException {
75 byte[] buffer = new byte[bufferSize];
76 int read = pipedInputStream.read(buffer);
78 throw new EOFException();
80 return Arrays.copyOf(buffer, read);
84 public void connect(Source source) throws ConnectException {
85 Preconditions.checkNotNull(source, "source must not be null");
89 final Process process = Runtime.getRuntime().exec(Iterables.toArray(ImmutableList.<String>builder().add(binary(source.format())).addAll(parameters(source.format())).build(), String.class));
90 final InputStream processOutput = process.getInputStream();
91 final OutputStream processInput = process.getOutputStream();
92 final InputStream processError = process.getErrorStream();
93 final PipedOutputStream pipedOutputStream = new PipedOutputStream();
94 pipedInputStream = new PipedInputStream(pipedOutputStream);
95 new Thread(new InputStreamDrainer(processError)).start();
96 new Thread(new Runnable() {
101 ByteStreams.copy(processOutput, pipedOutputStream);
102 } catch (IOException ioe1) {
103 /* okay, just exit. */
105 logger.finest("Reading stdout finished.");
108 new Thread(new Connection(source) {
111 protected int bufferSize() {
116 protected void feed(byte[] buffer) throws IOException {
117 processInput.write(buffer);
118 processInput.flush();
122 protected void finish() throws IOException {
123 processInput.close();
124 processOutput.close();
125 processError.close();
128 } catch (IOException ioe1) {
134 public void metadataUpdated() {
143 * Returns the location of the binary to execute.
146 * The format being processed
147 * @return The location of the binary to execute
149 protected abstract String binary(Format format);
152 * Returns the parameters for the binary.
155 * The format being processed
156 * @return The parameters for the binary
158 protected abstract Iterable<String> parameters(Format format);