Challenge 1 + 2

challenges/01-intro-challenges/java-env/HelloWorld.java

@@ -0,0 +1,5 @@
+public class HelloWorld {
+    public static void main(String[] args) {
+        System.out.println("Hello World");
+    }
+}

challenges/01-intro-challenges/java-env/Makefile

@@ -0,0 +1,7 @@
+run: HelloWorld.class
+	@ java HelloWorld
+
+HelloWorld.class: HelloWorld.java
+	@ javac $^
+
+.PHONY: run