ProcessBuilder和Runtime.exec之间的区别（） [英] Difference between ProcessBuilder and Runtime.exec()

问题描述

我正在尝试从java代码执行外部命令，但是我注意到 Runtime.getRuntime（）。exec（...）之间存在差异。和 new Process（...）。start（）。

I'm trying to execute an external command from java code, but there's a difference I've noticed between Runtime.getRuntime().exec(...) and new Process(...).start().

使用运行时：

Process p = Runtime.getRuntime().exec(installation_path + 
                                       uninstall_path + 
                                       uninstall_command + 
                                       uninstall_arguments);
p.waitFor();

exitValue为0且命令终止确定。

the exitValue is 0 and the command is terminated ok.

然而，使用 ProcessBuilder ：

Process p = (new ProcessBuilder(installation_path +    
                                 uninstall_path +
                                 uninstall_command,
                                 uninstall_arguments)).start();
p.waitFor();

退出值为1001，命令终止于中间，但 waitFor 返回。

the exit value is 1001 and the command terminates in the middle, although waitFor returns.

我应该如何解决 ProcessBuilder ？

推荐答案

的各种重载Runtime.getRuntime（）。exec（...）取一个字符串数组或一个字符串。 exec（）的单字符串重载将字符串标记为参数数组，然后将字符串数组传递给 exec（）之一带有字符串数组的重载。另一方面， ProcessBuilder 构造函数只接受字符串的varargs数组或字符串的 List 。假定数组或列表中的字符串是单个参数。无论哪种方式，获得的参数然后连接到一个字符串，传递给操作系统执行。

The various overloads of Runtime.getRuntime().exec(...) take either an array of strings or a single string. The single-string overloads of exec() will tokenise the string into an array of arguments, before passing the string array onto one of the exec() overloads that takes a string array. The ProcessBuilder constructors, on the other hand, only take a varargs array of strings or a List of strings, where each string in the array or list is assumed to be an individual argument. Either way, the arguments obtained are then joined up into a string that is passed to the OS to execute.

所以，例如，在Windows上，

So, for example, on Windows,

Runtime.getRuntime().exec("C:\DoStuff.exe -arg1 -arg2");

将运行 DoStuff.exe 程序两个给出的论点。在这种情况下，命令行会被标记化并重新组合在一起。但是，

will run a DoStuff.exe program with the two given arguments. In this case, the command-line gets tokenised and put back together. However,

ProcessBuilder b = new ProcessBuilder("C:\DoStuff.exe -arg1 -arg2");

将失败，除非碰巧有一个名称为 DoStuff的程序。 exe -arg1 -arg2 在 C：\ 中。这是因为没有标记化：假定运行的命令已被标记化。相反，你应该使用

will fail, unless there happens to be a program whose name is DoStuff.exe -arg1 -arg2 in C:\. This is because there's no tokenisation: the command to run is assumed to have already been tokenised. Instead, you should use

ProcessBuilder b = new ProcessBuilder("C:\DoStuff.exe", "-arg1", "-arg2");

或者

List<String> params = java.util.Arrays.asList("C:\DoStuff.exe", "-arg1", "-arg2");
ProcessBuilder b = new ProcessBuilder(params);

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