Add Minecraft 1.16 support

src/main/java/nl/rutgerkok/blocklocker/impl/BlockLockerPluginImpl.java

@@ -45,7 +45,7 @@
 import nl.rutgerkok.blocklocker.impl.group.TownyGroupSystem;
 import nl.rutgerkok.blocklocker.impl.group.mcMMOGroupSystem;
 import nl.rutgerkok.blocklocker.impl.location.TownyLocationChecker;
-import nl.rutgerkok.blocklocker.impl.nms.CNAccessor;
+import nl.rutgerkok.blocklocker.impl.nms.OldNMSAccessor;
 import nl.rutgerkok.blocklocker.impl.nms.NMSAccessor;
 import nl.rutgerkok.blocklocker.impl.nms.ServerSpecific;
 import nl.rutgerkok.blocklocker.impl.profile.ProfileFactoryImpl;
@@ -235,8 +235,8 @@ private Translator loadTranslations(String fileName) {
     public void onEnable() {
         // NMS checks
         try {
-            nms = new CNAccessor();
-        } catch (ClassNotFoundException e) {
+            nms = new OldNMSAccessor();
+        } catch (Exception e) {
             try {
                 nms = new NMSAccessor();
             } catch (Throwable t) {

src/main/java/nl/rutgerkok/blocklocker/impl/nms/NMSAccessor.java

@@ -3,6 +3,7 @@
 import java.lang.reflect.Constructor;
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
 import java.util.Optional;
 
 import org.bukkit.Bukkit;
@@ -15,7 +16,7 @@
 
 /**
  * Implementation of methods required by
- * nl.rutgerkok.chestsignprotect.impl.NMSAccessor for Minecraft 1.7.8 and 1.7.9.
+ * nl.rutgerkok.chestsignprotect.impl.NMSAccessor for Minecraft 1.16 and newer.
  *
  */
 public final class NMSAccessor implements ServerSpecific {
@@ -27,16 +28,7 @@ static Object call(Object on, Method method, Object... parameters) {
             throw new RuntimeException(e);
         }
     }
-
-    static Object enumField(Class<Enum<?>> enumClass, String name) {
-        try {
-            Method valueOf = getMethod(Enum.class, "valueOf", Class.class, String.class);
-            return invokeStatic(valueOf, enumClass, name);
-        } catch (Exception e) {
-            throw new RuntimeException(e);
-        }
-    }
-
+
     static Constructor<?> getConstructor(Class<?> clazz, Class<?>... paramTypes) {
         try {
             return clazz.getConstructor(paramTypes);
@@ -52,6 +44,30 @@ static Field getField(Class<?> clazz, String name) {
             throw new RuntimeException(e);
         }
     }
+
+    static Object getStaticFieldValue(Class<?> clazz, String name) {
+    	try {
+			return getField(clazz, name).get(null);
+		} catch (IllegalAccessException e) {
+			throw new RuntimeException(e);
+		}
+    }
+
+    static Object getStaticFieldValue(Class<?> clazz, Class<?> typeOfField) {
+    	for (Field field: clazz.getDeclaredFields()) {
+    		try {
+	    		field.setAccessible(true);
+	    		if ((field.getModifiers() & Modifier.STATIC) == Modifier.STATIC && typeOfField.isAssignableFrom(field.getType())) {
+	    			return field.get(null);
+	    		}
+    		} catch (SecurityException | IllegalAccessException e) {
+    			// Ignore, if we're only looking for public fields we can safely ignore errors on accessing private fields.
+    			// If we're accessing a private field, we'll get an error at the end of the method.
+    		}
+
+    	}
+    	throw new RuntimeException("No accessible static field found on " + clazz + " of type " + typeOfField);
+    }
 
     static Method getMethod(Class<?> clazz, String name, Class<?>... parameterTypes) {
         try {
@@ -96,7 +112,6 @@ static Object retrieve(Object on, Field field) {
     }
 
     private final String nmsPrefix;
-
     private final String obcPrefix;
 
     final Class<?> BlockPosition;
@@ -108,12 +123,15 @@ static Object retrieve(Object on, Field field) {
     final Constructor<?> ChatHoverable_new;
     final Class<?> ChatModifier;
     final Method ChatModifier_getGetHoverEvent;
-    final Constructor<?> ChatModifier_new;
+    final Object ChatModifier_defaultModifier;
     final Class<?> CraftChatMessage;
     final Method CraftChatMessage_fromComponent;
     final Class<?> CraftWorld;
     final Method CraftWorld_getHandle;
-    final Class<Enum<?>> EnumHoverAction;
+    /**
+     * Since Minecraft 1.16, this is not actually an enum anymore. Spigot didn't update the name, however.
+     */
+    final Class<?> EnumHoverAction;
     final Object EnumHoverAction_SHOW_TEXT;
     final Class<?> IChatBaseComponent;
     final Method IChatBaseComponent_getChatModifier;
@@ -135,7 +153,7 @@ public NMSAccessor() {
         ChatModifier = getNMSClass("ChatModifier");
         ChatHoverable = getNMSClass("ChatHoverable");
         IChatBaseComponent = getNMSClass("IChatBaseComponent");
-        EnumHoverAction = getAnyNMSEnum("EnumHoverAction", "ChatHoverable$EnumHoverAction");
+        EnumHoverAction = getNMSClass("ChatHoverable$EnumHoverAction");
         TileEntitySign = getNMSClass("TileEntitySign");
         ChatComponentText = getNMSClass("ChatComponentText");
 
@@ -152,12 +170,12 @@ public NMSAccessor() {
 
         ChatComponentText_new = getConstructor(ChatComponentText, String.class);
         BlockPosition_new = getConstructor(BlockPosition, int.class, int.class, int.class);
-        ChatModifier_new = getConstructor(ChatModifier);
-        ChatHoverable_new = getConstructor(ChatHoverable, EnumHoverAction, IChatBaseComponent);
+        ChatHoverable_new = getConstructor(ChatHoverable, EnumHoverAction, Object.class);
 
+        ChatModifier_defaultModifier = getStaticFieldValue(ChatModifier, ChatModifier);
         TileEntitySign_lines = getField(TileEntitySign, "lines");
 
-        EnumHoverAction_SHOW_TEXT = enumField(EnumHoverAction, "SHOW_TEXT");
+        EnumHoverAction_SHOW_TEXT = getStaticFieldValue(EnumHoverAction, "SHOW_TEXT");
     }
 
     private String chatComponentToString(Object chatComponent) {
@@ -265,7 +283,7 @@ private void setSecretData(Object tileEntitySign, String data) {
         Object line = ((Object[]) retrieve(tileEntitySign, TileEntitySign_lines))[0];
         Object modifier = call(line, IChatBaseComponent_getChatModifier);
         if (modifier == null) {
-            modifier = newInstance(ChatModifier_new);
+            modifier = ChatModifier_defaultModifier;
         }
         Object chatComponentText = newInstance(ChatComponentText_new, data);
         Object hoverable = newInstance(ChatHoverable_new, EnumHoverAction_SHOW_TEXT, chatComponentText);