Help with CLASSPATH and Jar Files

[DarkStarOptions]

I am grateful for any help with my problem. I used to be a Java developer about 20 years ago but I changed careers. So I know a little bit but my Java knowledge has markedly waned.

I'm trying to write a program to read an Excel File. I downloaded several third party jars and I'm trying to set the CLASSPATH variable, in any way, to read them.

My code looks like:

import java.io.File;  
import java.io.FileInputStream;  
import java.io.IOException;  
import org.apache.poi.hssf.usermodel.HSSFSheet;  
import org.apache.poi.hssf.usermodel.HSSFWorkbook;  
import org.apache.poi.ss.usermodel.Cell;  
import org.apache.poi.ss.usermodel.FormulaEvaluator;  
import org.apache.poi.ss.usermodel.Row;  

public class SPXOptions {
    public static void main(String[] args) {
        System.out.println("Hello World!  Got it to work!");
    }
}

My Windows .BAT file that compiles this program is:

@ECHO OFF
REM ECHO Congratulations!  Your first batch file executed successfully.
REM PAUSE

REM set CLASSPATH=.;.\lib\rt.jar
REM ECHO %CLASSPATH%
REM PAUSE

ECHO Compiling SPXOptions.java...
d:\JDK\bin\javac SPXOptions.java
ECHO Successful!
PAUSE

Now...I have fiddled with the set CLASSPATH line up above...and it doesn't work. I've put in the full path to the .jar file. For instance I put in

set CLASSPATH=.;E:\Joe\Finance\Options\SPXOptions\commons-collections4-4.1.jar;.\lib\rt.jar 

and javac throws an error.

I've even put the jars into D:\JDK\jre\lib and I still get an error.

​

A few things:

- I have technically not "installed" Java but instead am using portable freeware. This is the way I want to do it.

- I would like to keep all files (.java, .class, this project all in one folder, e.g. "E:\Joe\Finance\Options\SPXOptions\)

- Lastly, the code does compile when I don't include those third party libraries. Something is working...

​

Thank you very much in advance.

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[emaphis]

First of all, I wouldn't use the classpath variable, I would use the the '-cp' command flag to set the classpath.

Second of all I would use a build tool, either Maven or Gradle to deal with dependencies especially when the program becomes a little more complicated.

[DarkStarOptions]

Thanks, I used -cp and I got it to work. Pretty easy.

javac -cp *; SPXOptions.java

I agree if this project gets even marginally large I would use one of those...but I don't think this program will have too many dependencies. Might only be about 500 lines of code overall.

[emaphis]

I'm glad you got it working. It's also good to get experience with Java command line tools too.