How to pass parameters to a jar file and read the console output in ruby?

Question

I'm trying to execute a .jar file from ruby and read the output. The following solution works when my .jar file does not expect any parameters to be passed. But when I try to do this, I get an error -

pipe = IO.popen( [ '/path/to/java', '-jar', "/path/to/jarfile.jar #{argsA} #{argsB}", {SDTERR=>STDOUT} ] 
pipe.close_write 
puts pipe.readlines

I need to pass a couple of parameters to the .jar file. How can I acheive this? I've tried several ways to do this but wasn't successful. This is the error I get, where 'Hello' and 'World' are the arguments I'm passing -

Error: Unable to access jarfile jarfile.jar Hello World

Useful links: How to get java output with ruby

call jar file from ruby class

Have you tried passing the .jar filename and the arguments as separate elements in the array passed to `IO.popen`? — afternoon, Apr 23 '15 at 20:17

score 0 · Accepted Answer · answered Apr 23 '15 at 16:30

Put argsA and argsB in their own parameter, otherwise when seeing spaces in the parameters, ruby will surround them with quotes, so they're considered like one.

pipe = IO.popen( [ '/path/to/java', '-jar', '/path/to/jarfile.jar',"#{argsA}", "#{argsB}", {SDTERR=>STDOUT} ]

How to pass parameters to a jar file and read the console output in ruby?

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