Hello World - no dot.

Main.java

// imports can be inlined but excluded for readability
// import javax.script.SimpleScriptContext;
// import java.io.PrintWriter;

public class Main {
    public static void main(String[] args) {
        new SimpleScriptContext() {{
            new PrintWriter(writer) {{
                println("Hello World!");
                flush();
            }};
        }};
    }
}