I tried the code and i got the exception:
java.io.IOException: CreateProcess: vol > serial.out error=2 at java.lang.Win32Process.create(Native Method) at java.lang.Win32Process.<init>(Win32Process.java:66) at java.lang.Runtime.execInternal(Native Method) at java.lang.Runtime.exec(Runtime.java:551)
at java.lang.Runtime.exec(Runtime.java:418)
at java.lang.Runtime.exec(Runtime.java:361)
at java.lang.Runtime.exec(Runtime.java:325)
at serial.main(serial.java:14)