run command from vb

i want to create a java file .

the command is "javac filname.java" and i need to act in from the file path .

how can i create a command button that will do this command
from a path that i give her .

and how can i run any Dos command from VB .

10X !

Here ya go

Code:

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Dim filename$
filename = filename.java

Shell "javac " & filename, vbNormalFocus

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