refactor: Drop guava annotations and create annotation helper (#3389)

Core/src/main/java/com/plotsquared/core/plot/comment/CommentManager.java

@@ -25,7 +25,6 @@
  */
 package com.plotsquared.core.plot.comment;
 
-import com.google.common.annotations.Beta;
 import com.google.inject.TypeLiteral;
 import com.plotsquared.core.configuration.Settings;
 import com.plotsquared.core.configuration.caption.StaticCaption;
@@ -44,7 +43,6 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.concurrent.atomic.AtomicInteger;
 
-@Beta
 public class CommentManager {
 
     public static final HashMap<String, CommentInbox> inboxes = new HashMap<>();

Core/src/main/java/com/plotsquared/core/plot/flag/FlagContainer.java

@@ -28,11 +28,11 @@ package com.plotsquared.core.plot.flag;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableMap;
 import com.plotsquared.core.configuration.caption.CaptionUtility;
+import com.plotsquared.core.util.AnnotationHelper;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
-import org.jetbrains.annotations.ApiStatus;
 
 import java.util.Collection;
 import java.util.HashMap;
@@ -349,7 +349,7 @@ public class FlagContainer {
      *
      * @return a new Runnable that cleans up once the FlagContainer isn't needed anymore.
      */
-    @ApiStatus.Internal
+    @AnnotationHelper.ApiDescription(info = "This method should not be considered as public or API.")
     public Runnable createCleanupHook() {
         return () -> GlobalFlagContainer.getInstance().unsubscribe(unknownsRef);
     }

Core/src/main/java/com/plotsquared/core/util/AnnotationHelper.java

@@ -0,0 +1,62 @@
+/*
+ *       _____  _       _    _____                                _
+ *      |  __ \| |     | |  / ____|                              | |
+ *      | |__) | | ___ | |_| (___   __ _ _   _  __ _ _ __ ___  __| |
+ *      |  ___/| |/ _ \| __|\___ \ / _` | | | |/ _` | '__/ _ \/ _` |
+ *      | |    | | (_) | |_ ____) | (_| | |_| | (_| | | |  __/ (_| |
+ *      |_|    |_|\___/ \__|_____/ \__, |\__,_|\__,_|_|  \___|\__,_|
+ *                                    | |
+ *                                    |_|
+ *            PlotSquared plot management system for Minecraft
+ *                  Copyright (C) 2021 IntellectualSites
+ *
+ *     This program is free software: you can redistribute it and/or modify
+ *     it under the terms of the GNU General Public License as published by
+ *     the Free Software Foundation, either version 3 of the License, or
+ *     (at your option) any later version.
+ *
+ *     This program is distributed in the hope that it will be useful,
+ *     but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *     GNU General Public License for more details.
+ *
+ *     You should have received a copy of the GNU General Public License
+ *     along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.plotsquared.core.util;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import static java.lang.annotation.ElementType.METHOD;
+import static java.lang.annotation.ElementType.MODULE;
+import static java.lang.annotation.ElementType.PACKAGE;
+import static java.lang.annotation.ElementType.RECORD_COMPONENT;
+import static java.lang.annotation.ElementType.TYPE;
+
+/**
+ * @since 6.3.0
+ */
+@AnnotationHelper.ApiDescription(info = "An internal class for custom annotations." +
+        "This is in no form part of the API and is subject to change at any time.")
+public final class AnnotationHelper {
+
+    private AnnotationHelper() {
+    }
+
+    @Documented
+    @Retention(RetentionPolicy.CLASS)
+    @Target(value = {METHOD, PACKAGE, MODULE, RECORD_COMPONENT, TYPE})
+    public @interface ApiDescription {
+        /**
+         * Returns additional information how to use a class for the API
+         *
+         * @return the version string
+         * @since 6.3.0
+         */
+        String info() default "";
+    }
+
+}

Core/src/main/java/com/plotsquared/core/util/EventDispatcher.java

@@ -83,13 +83,13 @@ import com.sk89q.worldedit.world.block.BlockTypes;
 import net.kyori.adventure.text.minimessage.Template;
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
-import org.jetbrains.annotations.ApiStatus;
 
 import java.util.ArrayList;
 import java.util.List;
 import java.util.UUID;
 
-@ApiStatus.Internal
+@AnnotationHelper.ApiDescription(info = "This is an internal class used by PlotSquared to dispatch events." +
+        "This is in no form part of the API and is subject to change at any time.")
 public class EventDispatcher {
 
     private final EventBus eventBus = new EventBus("PlotSquaredEvents");