Bare-bones Java project build

Source: Apache Ant Manual

We have to create only the src directory. (Because I am working on Windows, here is the Windows syntax—translate to your shell):

md src

The following simple Java class just prints a fixed message out to STDOUT, so just write this code into src\oata\HelloWorld.java.

package oata;

public class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Hello World");
    }
}

Now just try to compile and run that:

md build\classes
javac -sourcepath src -d build\classes src\oata\HelloWorld.java
java -cp build\classes oata.HelloWorld

which will result in

Hello World

Creating a jar-file is not very difficult. But creating a startable jar-file needs more steps: create a manifest-file containing the start class, creating the target directory and archiving the files.

echo Main-Class: oata.HelloWorld>myManifest
md build\jar
jar cfm build\jar\HelloWorld.jar myManifest -C build\classes .
java -jar build\jar\HelloWorld.jar

jflopezfernandez/java-build.md