Question

I want to create database import using .sql file with java then I found a code something like this

Runtime rt = Runtime.getRuntime();
Process pr = rt.exec(new String[]{"/bin/bash","-c","mysql -p -h localhost test < "+fileName.toString()});

I’m using netbean to run my desktop app. then I got this error message

java.io.IOException: Cannot run program "/bin/bash": CreateProcess error=2, The system cannot find the file specified

my question is where can i find /bin/bash path? or what should i do…
should I configure something like env variable path?

I’m running this on windows

solution is replacing /bin/bash with cmd.exe and -c to /c, but when I execute the program I got this message appear on my console

‘mysql’ is not recognized as an internal or external command,
operable program or batch file.

though I already setup mysql directory in PATH environment variable of Windows

Answer 1

/bin/bash doesn’t exist on Windows. Try replacing /bin/bash with cmd.exe, and replacing the switch -c with /c.

EDIT: if your Java program appears to complete successfully but no data has been written, it is quite possible that your Java program didn’t wait for the mysql process to complete. Try adding pr.waitFor();.

Alternatively, mysql could be reporting an error message or writing something to its standard output or standard error streams. If this is the case, you’ll need to either:

1. read the offending stream(s), or
2. if you’re sure you can ignore it, redirect the offending stream(s) to NUL.

You can redirect standard output to NUL by adding >NUL to the command line, and redirect standard error to NUL by adding 2>NUL.

I woudn’t recommend discarding the output/error messages. If there’s an error, how will you know about it? However, it’s difficult to properly handle the standard output and standard error streams of processes generated using Runtime.getRuntime().exec(...). Instead, I would use a ProcessBuilder. A ProcessBuilder allows you to redirect the mysql process’s standard error into the standard output, which makes reading the output from both streams a bit easier (you don’t need two separate threads).

ProcessBuilder builder = new ProcessBuilder("cmd.exe", "/c", "mysql -p -h localhost test < "+fileName.toString());
builder.redirectErrorStream(true);
Process pr = builder.start();

// Get mysql process's standard output/error.
InputStream is = pr.getInputStream();

// Now read from it and write it to standard output.
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
String line = reader.readLine();
while (line != null) {
    System.out.println(line);
    line = reader.readLine();
}