Gitlab-ci for java project

I trying to config gitlab-ci file for java project without Maven, Gradle, etc. This is my file:

image: java:latest

stages:
    - build

build:
    stage: build
    script: 
        - '"C:\Program Files\Java\jdk1.8.0_181\bin\javac" StockServer.java'
    artifacts:
        paths:
         - StockServer.*

But my runner install on remote computer, so it can not find StockServer.java (in example HelloWorld.java was in the same directory). How should I set path to file at runners directory? And will it be a compilation of all project (StockServer contains main())? Or just this class?