Creating a batch file, for simple javac and java command execution

Question

It is a really simple thing but I cannot get my head around it. I have looked at plenty of StackOverFlow post and as well as on internet.

My goal is to create a .bat whi

Answer 1

I've also faced a similar situation where I needed a script which can take care of javac and then java(ing) my java program. So, I came up with this BATCH script.

::  @author Rudhin Menon
::  Created on 09/06/2015
::
::  Auto-Concrete is a build tool, which monitor the file under
::  scrutiny for any changes, and compiles or runs the same once
::  it got changed.
::  
::  ========================================
::  md5sum and gawk programs are prerequisites for this script.
::  Please download them before running auto-concrete.
::  ========================================
::  
::  Happy coding ...

@echo off

:: if filename is missing
if [%1] EQU [] goto usage_message

:: Set cmd window name
title Auto-Concrete v0.2

cd versions

if %errorlevel% NEQ 0 (
    echo creating versions directory
    mkdir versions
    cd versions
)

cd ..

javac "%1"

:loop
    :: Get OLD HASH of file
    md5sum "%1" | gawk '{print $1}' > old
    set /p oldHash= new
    set /p newHash=nul
        goto inner_loop
    )

    :: Once they differ, compile the source file
    :: and repeat everything again
    echo.
    echo ========= %1 changed on %DATE% at %TIME% ===========
    echo.       
    javac "%1"
goto loop

:usage_message
echo Usage : auto-concrete FILENAME.java

Above batch script will check the file for any changes and compile if any changes are done, you can tweak it for compiling whenever you want. Happy coding :)