CODEWITHSUNDEEP
scala
Valli69
Valli69

Reputation: 9892

How to execute shell script (.sh file) in scala program

I'm new to Scala programming. I have one .sh file. I want to run this file using Scala. I have tried solutions provided in the below link. But those are not working for me.

Execute shell script from scala application

I have tried simple echo command in scala REPL and it's working fine. But when I used the same line of code in Scala program I am getting java.io.IOException like below.

Exception in thread "main" java.io.IOException: Cannot run program "echo": CreateProcess error=2, The system cannot find the file specified

And my sample code looks like below

import java.io._
import sys.process._
object POC {  
  def main( args: Array[String]) {     
    val p = "echo 'hello world'".!!
    println("#############################################       "+ p)   
  }
}

EDIT: As per the Tom's response, I have modified above code like below and it's working fine now and getting Hello world in console.

    import java.io._
    import sys.process._
    object POC {  
      def main( args: Array[String]) {     
        val p = Seq("echo", "hello world")
        val os = sys.props("os.name").toLowerCase
        val panderToWindows = os match {
           case x if x contains "windows" => Seq("cmd", "/C") ++ command
           case _ => command
        }
        panderToWindows.!  
      }
    }

Now my exact issue is to execute my script.sh file. I have directory like below.

src
- bin
  - script.sh
- scala
  - POC.scala

script.sh code:

#!/bin
echo "Hello world"

And my POC.scala consists below code.

        import java.io._
        import sys.process._
        object POC {  
          def main( args: Array[String]) {     
            val command = Seq("/bin/script.sh")
            val os = sys.props("os.name").toLowerCase
            val panderToWindows = os match {
               case x if x contains "windows" => Seq("cmd", "/C") ++ command
               case _ => command
            }
            panderToWindows.!  
          }
        }

I didn't get any console output after executing above code. Please let me know if I missed anything. Thanks.

Upvotes: 1

Views: 4024

Answers (1)

jihor
jihor

Reputation: 2599

Assuming Linux is used, one can start with a simple "pwd"!, which will display the working directory, and then invoke the shell script using relative or absolute path. E.g.:

import sys.process._

object POC extends App{
  val path = "pwd".!!.trim
  println(path)
  s"$path/src/main/bin/test.sh".!
  "src/main/bin/test.sh".!
}

returns: 

/home/user/temp/scala-shell-script
Hello shell
Hello shell

BTW, shell scripts usually have #!/bin/sh (not #!/bin) in the shebang line: 

#!/bin/sh
echo "Hello shell"

Upvotes: 2

Related Questions