(这是我的同事在其他地方发布的一个问题,但我想我会在这里发布,看看我是否能够吸引不同的观众.)
大家好,我正在测试编写一个小型Java应用程序的可能性,它将使用Psexec启动远程作业.在测试将java程序的stdin和stdout绑定到psexec的过程中,我遇到了一个奇怪的错误.
我的测试程序是一个基本的echo程序.它启动一个线程从stdin读取,然后将读取输出直接传递回stdout.当在本地机器上运行时,而不是从psexec运行时,它运行得很漂亮.正是应该的.
但是,当我从PsExec调用它时,第一次将输入直接传送到stdout时它会丢失.是什么让这个错误真的很棒,它只是第一次将输入直接输入stdout而丢失了.如果输入String附加到另一个字符串,它可以正常工作.String字符串或String变量.但是,如果输入String直接发送到stdout,则它不会通过.它第二次发送到stdout它经历了很好的 - 每次都在那之后.
我完全不知道这里发生了什么.我试图测试我能想到的每一个可能的错误.我没有想法.我错过了一个或者这只是psexec里面的东西吗？
这是有问题的代码,它有三个类(其中一个实现了一个单一函数interace的接口).
主类:
public class Main {
public static void main(String[] args) {
System.out.println("Starting up.");
CReader input = new CReader(new BufferedReader(
new InputStreamReader(System.in)));
CEcho echo = new CEcho();
input.addInputStreamListener(echo);
input.start();
System.out.println("Successfully started up. Awaiting input.");
}
}
CReader类,它是从stdin读取的线程:
public class CReader extends Thread {
private ArrayList<InputStreamListener> listeners =
new ArrayList<InputStreamListener>();
private boolean exit = false;
private Reader in;
public CReader(Reader in) {
this.in = in;
}
public void addInputStreamListener(InputStreamListener listener) {
listeners.add(listener);
}
public void fireInputRecieved(String input) {
if(input.equals("quit"))
exit = true;
System.out.println("Input string has made it to fireInputRecieved: "
+ input);
for(int index = 0; index < listeners.size(); index++)
listeners.get(index).inputRecieved(input);
}
@Override
public void run() {
StringBuilder sb = new StringBuilder();
int current = 0, last = 0;
while (!exit) {
try {
current = in.read();
}
catch (IOException e) {
System.out.println("Encountered IOException.");
}
if (current == -1) {
break;
}
else if (current == (int) '\r') {
if(sb.toString().length() == 0) {
// Extra \r, don't return empty string.
continue;
}
fireInputRecieved(new String(sb.toString()));
sb = new StringBuilder();
}
else if(current == (int) '\n') {
if(sb.toString().length() == 0) {
// Extra \n, don't return empty string.
continue;
}
fireInputRecieved(new String(sb.toString()));
sb = new StringBuilder();
}
else {
System.out.println("Recieved character: " + (char)current);
sb.append((char) current);
last = current;
}
}
}
}
CEcho类,它是将它传回stdout的类:
public class CEcho implements InputStreamListener {
public void inputRecieved(String input) {
System.out.println("\n\nSTART INPUT RECIEVED");
System.out.println("The input that has been recieved is: "+input);
System.out.println("It is a String, that has been copied from a " +
"StringBuilder's toString().");
System.out.println("Outputting it cleanly to standard out: ");
System.out.println(input);
System.out.println("Outputting it cleanly to standard out again: ");
System.out.println(input);
System.out.println("Finished example outputs of input: "+input);
System.out.println("END INPUT RECIEVED\n\n");
}
}
最后,这是程序输出:
>psexec \\remotecomputer "C:\Program Files\Java\jre1.6.0_05\bin\java.exe" -jar "C:\Documents and Settings\testProram.jar" PsExec v1.96 - Execute processes remotely Copyright (C) 2001-2009 Mark Russinovich Sysinternals - www.sysinternals.com Starting up. Successfully started up. Awaiting input. Test Recieved character: T Recieved character: e Recieved character: s Recieved character: t Input string has made it to fireInputRecieved: Test START INPUT RECIEVED The input that has been recieved is: Test It is a String, that has been copied from a StringBuilder's toString(). Outputting it cleanly to standard out: Outputting it cleanly to standard out again: Test Finished example outputs of input: Test END INPUT RECIEVED
您是否尝试过将输出重定向到文件（ java... >c:\output.txt ）？这样你就可以仔细检查所有内容是否都进入标准输出，并且可能只是被 psexec 吃掉