[Bleeding] Add missing methods to Bukkit class, fix non-static methods, and add a junit test to ensure both these problems will be caught in future.

By: Celtic Minstrel <celtic.minstrel.ca@some.place>

paper-api/src/main/java/org/bukkit/Bukkit.java

@@ -194,19 +194,19 @@ public final class Bukkit {
         return server.addRecipe(recipe);
     }
 
-    public List<Recipe> getRecipesFor(ItemStack result) {
+    public static List<Recipe> getRecipesFor(ItemStack result) {
         return server.getRecipesFor(result);
     }
 
-    public Iterator<Recipe> recipeIterator() {
+    public static Iterator<Recipe> recipeIterator() {
         return server.recipeIterator();
     }
 
-    public void clearRecipes() {
+    public static void clearRecipes() {
         server.clearRecipes();
     }
 
-    public void resetRecipes() {
+    public static void resetRecipes() {
         server.resetRecipes();
     }
 
@@ -289,4 +289,36 @@ public final class Bukkit {
     public static Messenger getMessenger() {
         return server.getMessenger();
     }
+
+    public static boolean getAllowEnd() {
+        return server.getAllowEnd();
+    }
+
+    public static File getUpdateFolderFile() {
+        return server.getUpdateFolderFile();
+    }
+
+    public static int getTicksPerAnimalSpawns() {
+        return server.getTicksPerAnimalSpawns();
+    }
+
+    public static int getTicksPerMonsterSpawns() {
+        return server.getTicksPerMonsterSpawns();
+    }
+
+    public static boolean useExactLoginLocation() {
+        return server.useExactLoginLocation();
+    }
+
+    public static GameMode getDefaultGameMode() {
+        return server.getDefaultGameMode();
+    }
+
+    public static void setDefaultGameMode(GameMode mode) {
+        server.setDefaultGameMode(mode);
+    }
+
+    public static OfflinePlayer[] getOfflinePlayers() {
+        return server.getOfflinePlayers();
+    }
 }

paper-api/src/test/java/org/bukkit/BukkitMirrorTest.java

@@ -0,0 +1,19 @@
+package org.bukkit;
+
+import static org.junit.Assert.*;
+
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
+
+import org.junit.Test;
+
+public class BukkitMirrorTest {
+    @Test
+    public final void test() throws NoSuchMethodException {
+        Method[] serverMethods = Server.class.getDeclaredMethods();
+        for(Method method : serverMethods) {
+            Method mirrorMethod = Bukkit.class.getDeclaredMethod(method.getName(), method.getParameterTypes());
+            assertTrue("Bukkit." + method.getName() + " must be static!", Modifier.isStatic(mirrorMethod.getModifiers()));
+        }
+    }
+}