Add simple JavaFX application

.gitignore

-build
+# Created by https://www.gitignore.io/api/java,gradle
+# Edit at https://www.gitignore.io/?templates=java,gradle
+
+### Java ###
+# Compiled class file
+*.class
+
+# Log file
+*.log
+
+# BlueJ files
+*.ctxt
+
+# Mobile Tools for Java (J2ME)
+.mtj.tmp/
+
+# Package Files #
+*.jar
+*.war
+*.nar
+*.ear
+*.zip
+*.tar.gz
+*.rar
+
+# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
+hs_err_pid*
+
+### Gradle ###
 .gradle
-.idea
+build/
+
+# Ignore Gradle GUI config
+gradle-app.setting
+
+# Avoid ignoring Gradle wrapper jar file (.jar files are usually ignored)
+!gradle-wrapper.jar
+
+# Cache of project
+.gradletasknamecache
+
+# # Work around https://youtrack.jetbrains.com/issue/IDEA-116898
+# gradle/wrapper/gradle-wrapper.properties
+
+### Gradle Patch ###
+**/build/
+
+# End of https://www.gitignore.io/api/java,gradle
\ No newline at end of file

build.gradle

@@ -4,9 +4,9 @@ plugins {
 
 apply plugin: 'application'
 
-mainClassName = 'Main'
+mainClassName = 'com.avatarduel.AvatarDuel'
 
-group 'org.example'
+group 'com.avatarduel'
 version '1.0-SNAPSHOT'
 
 sourceCompatibility = 1.8

src/main/java/AvatarDuel.java

+package com.avatarduel;
+
+import javafx.application.Application;
+import javafx.scene.Group;
+import javafx.scene.Scene;
+import javafx.scene.text.Text;
+import javafx.stage.Stage;
+
+public class AvatarDuel extends Application {
+
+  @Override
+  public void start(Stage stage) {
+    Text text = new Text();
+    text.setText("Avatar Duel!");
+    text.setX(50);
+    text.setY(50);
+
+    Group root = new Group();
+    root.getChildren().add(text);
+
+    Scene scene = new Scene(root, 1280, 720);
+
+    stage.setTitle("Avatar Duel");
+    stage.setScene(scene);
+    stage.show();
+  }
+
+  public static void main(String[] args) {
+    launch();
+  }
+}
\ No newline at end of file

src/main/java/Main.java

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