Added Goal<T>, which EntityGoal<T> and TargetGoal<T> extend from, giving them a shared parent class

eco-api/src/main/java/com/willfp/eco/core/entities/ai/EntityGoal.java

@@ -8,14 +8,8 @@ import org.jetbrains.annotations.NotNull;
  *
  * @param <T> The type of mob that the goal can be applied to.
  */
-public interface EntityGoal<T extends Mob> {
-    /**
-     * Add the entity goal to an entity.
-     *
-     * @param entity   The entity.
-     * @param priority The priority.
-     * @return The entity, modified.
-     */
+public interface EntityGoal<T extends Mob> extends Goal<T> {
+    @Override
     default T addToEntity(@NotNull T entity, int priority) {
         return EntityController.getFor(entity)
                 .addEntityGoal(priority, this)

eco-api/src/main/java/com/willfp/eco/core/entities/ai/Goal.java

@@ -0,0 +1,24 @@
+package com.willfp.eco.core.entities.ai;
+
+import org.bukkit.entity.Mob;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * A generic goal for entity AI.
+ *
+ * @param <T> The type of mob that the goal can be applied to.
+ */
+public interface Goal<T extends Mob> {
+    /**
+     * Add the entity goal to an entity.
+     * <p>
+     * The lower the priority, the higher up the execution order; so
+     * priority 0 will execute first. Lower priority (higher number) goals
+     * will only execute if all higher priority goals are stopped.
+     *
+     * @param entity   The entity.
+     * @param priority The priority.
+     * @return The entity, modified.
+     */
+    T addToEntity(@NotNull T entity, int priority);
+}

eco-api/src/main/java/com/willfp/eco/core/entities/ai/TargetGoal.java

@@ -8,14 +8,8 @@ import org.jetbrains.annotations.NotNull;
  *
  * @param <T> The type of mob that the goal can be applied to.
  */
-public interface TargetGoal<T extends Mob> {
-    /**
-     * Add the target goal to an entity.
-     *
-     * @param entity   The entity.
-     * @param priority The priority.
-     * @return The entity, modified.
-     */
+public interface TargetGoal<T extends Mob> extends Goal<T> {
+    @Override
     default T addToEntity(@NotNull T entity, int priority) {
         return EntityController.getFor(entity)
                 .addTargetGoal(priority, this)