ProcessBuilder redirecting output

Question

I am trying to redirect output of a process started with the help of ProcessBuilder using following code

ProcessBuilder pb = new ProcessBuilder("/myScript >> /myLogFile 2>&1 <& - &");
Map<String, String> env = pb.environment();
env.clear();
env.put("var1", "val1");
env.put("var2", "val2");
pb.redirectErrorStream(true);
Process p = pb.start();

But it failed with exception

Exception in thread "main" java.io.IOException: Cannot run program "/myScript >> /myLogFile 2>&1 <& - &": java.io.IOException: error=2, No such file or directory at java.lang.ProcessBuilder.start(ProcessBuilder.java:460)

It works fine when I just pass "/myScript"

Script is perl, any suggestions/coments on why it is failing?

I tried passing all of them as seperate arguments like new ProcessBuilder("/myScript",">>","/myLogFile"), it executes but it does not redirect to log file and also it does not take envVars.

Answer 1

Shell redirection operators are unknown to ProcessBuilder. Put your command in a shell script and execute it, as shown here. Alternatively, use bash -c, as shown here.

Answer 2

As you specified, from Java7 you can keep using ProcessBuilder with the only executable file as parameter and redirect/intercept its output stream, using redirectInput() redirectOutput() and redirectError() from ProcessBuilder class.