001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017 018package org.apache.commons.net.examples.util; 019 020import java.io.IOException; 021import java.io.InputStream; 022import java.io.OutputStream; 023 024import org.apache.commons.net.io.Util; 025import org.apache.commons.net.util.NetConstants; 026 027/** 028 * 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 029 * 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 030 * 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 031 * threads terminate when the remote input source closes. 032 */ 033 034public final class IOUtil { 035 036 public static void readWrite(final InputStream remoteInput, final OutputStream remoteOutput, final InputStream localInput, final OutputStream localOutput) { 037 final Thread reader; 038 final Thread writer; 039 040 reader = new Thread(() -> { 041 int ch; 042 043 try { 044 while (!Thread.interrupted() && (ch = localInput.read()) != NetConstants.EOS) { 045 remoteOutput.write(ch); 046 remoteOutput.flush(); 047 } 048 } catch (final IOException e) { 049 // e.printStackTrace(); 050 } 051 }); 052 053 writer = new Thread(() -> { 054 try { 055 Util.copyStream(remoteInput, localOutput); 056 } catch (final IOException e) { 057 e.printStackTrace(); 058 System.exit(1); 059 } 060 }); 061 062 writer.setPriority(Thread.currentThread().getPriority() + 1); 063 064 writer.start(); 065 reader.setDaemon(true); 066 reader.start(); 067 068 try { 069 writer.join(); 070 reader.interrupt(); 071 } catch (final InterruptedException e) { 072 // Ignored 073 } 074 } 075 076}