在Scala中调用外部命令作为子进程

Question

在Python中,如果我想将外部命令作为子进程调用,我会执行以下操作:

from subprocess import Popen, PIPE
cmd = ['cat', '-be']
out, err = Popen(cmd, stdin=PIPE, stdout=PIPE, stderr=PIPE).communicate("some input")

在Scala中执行相同操作的标准方法是什么？使用Java的ProcessBuilder我提出了以下内容,但它非常难看:

def communicate(cmd: List[String], input: Option[String] = None): (String, String) = {

    val command = new java.util.ArrayList[String]()
    cmd.foreach(command.add(_))

    val builder = new ProcessBuilder(command)
    val process = builder.start()

    val stdinWriter = new java.io.PrintWriter((new java.io.OutputStreamWriter(new java.io.BufferedOutputStream(process.getOutputStream()))), true);
    val stdoutReader = new java.io.BufferedReader(new java.io.InputStreamReader(process.getInputStream()))
    val stderrReader = new java.io.BufferedReader(new java.io.InputStreamReader(process.getErrorStream()))

    input.foreach(stdinWriter.write(_))
    stdinWriter.close()

    def read(reader: java.io.BufferedReader): String = {
        val out = new ListBuffer[String]
        var line: String = reader.readLine()
        while (line != null) {
            out += line
            line = reader.readLine()
        }
        return out.result.mkString("\n")
    }

    val stdout = read(stdoutReader)
    val stderr = read(stderrReader)

    stdoutReader.close()
    stderrReader.close()

    return (stdout, stderr)

}

val (catout, caterr) = communicate(List("cat", "-be"), Some("some input"))
val (pwdout, pwderr) = communicate(List("pwd"))

Scala中是否有更好的替代品？

Answer 1

这里的答案Scala 2.9的"scala.sys.process"如何工作？演示了如何使用新的Scala 2.9 scala.sys.process.Process.如果你不使用2.9,你可以使用sbt的过程部分; Scala进程源自哪个.