1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18 package org.apache.commons.net.examples.util;
19
20 import java.io.IOException;
21 import java.io.InputStream;
22 import java.io.OutputStream;
23
24 import org.apache.commons.net.io.Util;
25 import org.apache.commons.net.util.NetConstants;
26
27 /**
28 * This is a utility class providing a reader/writer capability required by the weatherTelnet, rexec, rshell, and rlogin example programs. The only point of the
29 * class is to hold the static method readWrite which spawns a reader thread and a writer thread. The reader thread reads from a local input source (presumably
30 * stdin) and writes the data to a remote output destination. The writer thread reads from a remote input source and writes to a local output destination. The
31 * threads terminate when the remote input source closes.
32 */
33
34 public final class IOUtil {
35
36 public static void readWrite(final InputStream remoteInput, final OutputStream remoteOutput, final InputStream localInput, final OutputStream localOutput) {
37 final Thread reader;
38 final Thread writer;
39
40 reader = new Thread(() -> {
41 int ch;
42
43 try {
44 while (!Thread.interrupted() && (ch = localInput.read()) != NetConstants.EOS) {
45 remoteOutput.write(ch);
46 remoteOutput.flush();
47 }
48 } catch (final IOException e) {
49 // e.printStackTrace();
50 }
51 });
52
53 writer = new Thread(() -> {
54 try {
55 Util.copyStream(remoteInput, localOutput);
56 } catch (final IOException e) {
57 e.printStackTrace();
58 System.exit(1);
59 }
60 });
61
62 writer.setPriority(Thread.currentThread().getPriority() + 1);
63
64 writer.start();
65 reader.setDaemon(true);
66 reader.start();
67
68 try {
69 writer.join();
70 reader.interrupt();
71 } catch (final InterruptedException e) {
72 // Ignored
73 }
74 }
75
76 }