从java执行终端命令 [英] Executing terminal commands from java

问题描述

我知道有很多线程，但没有一个为我工作。这里是我想做的：

I know there are many threads about this, but none of them worked for me. Here is what I am trying to do:

Javac并从我的java代码运行一个文件。它适用于Windows，但我想让它也在UNIX上工作。代码如下：

Javac and run a file from my java code. It works for Windows but I would like to make it also work on UNIX. Here the code:

if(os.equals("win")){
        //For Windows
        try {
            Runtime.getRuntime().exec(
                            "cmd /c start cmd.exe /K "
                            + "\"cd " + path + "&& "
                            + "javac " + name + ".java && "
                            + "echo ^>^>" + name + ".java " + "outputs: &&"
                            + "echo. &&"
                            + "java " + name + " && "
                            + "echo. &&"
                            + "pause && "
                            + "exit\"");
        } catch (IOException e) {
            System.out.println("Didn't work");
        }
    }else{
        try {
            //TODO make it work for UNIX
            Runtime.getRuntime().exec("");
        } catch (IOException e) {
            System.out.println("Didn't work");
        }
    }

问题是，在UNIX系统上，不可预测的
例如：

The problem is, that on UNIX systems it acts "unpredictable" For exemple:

Runtime.getRuntime().exec("open image.png");

打开图片，但

Runtime.getRuntime().exec("javac Test.java");
Runtime.getRuntime().exec("echo 'hello'");

它什么都不做。无按摩。

It does nothing. No Massage.

我非常感谢任何输入。

UPDATE ------ -------------------------------------------------- ----

看起来像Windows CMD，Terminal需要一个InputStreamReader来显示exec中发生的事情。我发现这个代码在另一个线程，现在至少我从exec终端的一些输出。

It seems like in contrast to Windows CMD, Terminal needs a InputStreamReader to display what happened in exec. I found this code in another thread and now at least I get some output from the exec Terminal.

   String line;
   Process p = Runtime.getRuntime().exec( "echo HelloWorld2" );

   BufferedReader in = new BufferedReader(
           new InputStreamReader(p.getInputStream()) );
   while ((line = in.readLine()) != null) {
     System.out.println(line);
   }
   in.close();

但是事情仍然是神秘的，因为执行

But things still remain misterious, because executing

Process p = Runtime.getRuntime（）。exec（javac Test.java）;

Process p = Runtime.getRuntime().exec("javac Test.java");

工作并生成Test.class文件。

works and generates a Test.class file. But

Process p = Runtime.getRuntime（）。exec（javac Test.java& java Test）; p>

Process p = Runtime.getRuntime().exec("javac Test.java && java Test");

不做任何事情（没有发生任何事情，终端执行没有错误按摩。）在Terminal中手动键入，建立并按预期运行。我缺少什么？

does nothing.(Nothing happens. Terminal "executes" without error massages.) Typing this manually in Terminal builds and runs as expected. What am I missing?

推荐答案

我没有Linux系统可以玩，上面的第二个命令试图编译名为Test.java，&&，java和Test的Java文件。换句话说，Runtime.exec（）方法以字面方式处理参数，而不是应用shell解释。

I don't have a Linux system here to play with, but I'm pretty certain that the second command above is trying to compile Java files named "Test.java", "&&", "java" and "Test"; in other words the Runtime.exec() method treats arguments literally instead of applying shell interpretation.

您可能需要处理以下内容：

You could probably get it to work with something along the lines of:

Process p = Runtime.getRuntime().exec(
    new String[] { "sh",  "-c", "javac Test.java && java Test" });

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