Run batch file using Runtime.exec without using cmd.exe

Question

I am running a Java application that executes a script. The relevant code is

    String command [] = new String [2];
    command[0] =  "customSearch";
    command[1] =  query;    

    Process process = Runtime.getRuntime().exec(command);

This code runs on Linux because I placed a script called customSearch in the /usr/bin directory. In a similar way, I created a batch file in Windows called customSearch.bat and made sure it is on the PATH. However, this Java code will not work on Windows because "Batch files alone are not executable" as this thread mentions.

So to get it to work on Windows, I would have to say

    command[0] =  "cmd /c start customSearch";

However, I do not want to do this because this won't work on Linux. How can I run the batch file on Windows without changing command[0] ?

Answer 1

You can add a check if the OS is Windows and then execute a custom-windows-batch-runner-snippet.

For example, I created a simple test.bat file with a netstat command within:

netstat

Here's how I executed it by a Java snippet:

String os = System.getProperty("os.name");
if (os.toLowerCase().indexOf("win") >= 0) {
    command = new String[1];
    command[0] = "test.bat";  

    Process process = Runtime.getRuntime().exec(command);
    BufferedReader is = new BufferedReader(
                            new InputStreamReader(process.getInputStream()));
    String line;
    while ((line = is.readLine()) != null) {
       System.out.println(line);
    }
}

This is the result in the console:

D:\workspace\SO>netstat

Active Connections

  Proto  Local Address          Foreign Address        State
  TCP    127.0.0.1:19872        hp:49266               ESTABLISHED
  TCP    127.0.0.1:49169        hp:49170               ESTABLISHED
  TCP    127.0.0.1:49170        hp:49169               ESTABLISHED'
....

Even better, you can wrap every OS-specific command-executing snippets with if statements.