SPIGOT-7195, SPIGOT-7197: Add DataPack API

By: Doc <nachito94@msn.com>

paper-api/src/main/java/org/bukkit/packs/DataPackManager.java

@@ -0,0 +1,70 @@
+package org.bukkit.packs;
+
+import java.util.Collection;
+import org.bukkit.Material;
+import org.bukkit.NamespacedKey;
+import org.bukkit.World;
+import org.bukkit.entity.EntityType;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * Manager of data packs.
+ */
+@ApiStatus.Experimental
+public interface DataPackManager {
+
+    /**
+     * Return all the available {@link DataPack}s on the server.
+     *
+     * @return a Collection of {@link DataPack}
+     */
+    @NotNull
+    public Collection<DataPack> getDataPacks();
+
+    /**
+     * Gets a {@link DataPack} by its key.
+     *
+     * @param dataPackKey the key of the {@link DataPack}
+     * @return the {@link DataPack} or null if it does not exist
+     */
+    @Nullable
+    public DataPack getDataPack(@NotNull NamespacedKey dataPackKey);
+
+    /**
+     * Return all the enabled {@link DataPack} in the World.
+     *
+     * @param world the world to search
+     * @return a Collection of {@link DataPack}
+     */
+    @NotNull
+    public Collection<DataPack> getEnabledDataPacks(@NotNull World world);
+
+    /**
+     * Return all the disabled {@link DataPack} in the World.
+     *
+     * @param world the world to search
+     * @return a Collection of {@link DataPack}
+     */
+    @NotNull
+    public Collection<DataPack> getDisabledDataPacks(@NotNull World world);
+
+    /**
+     * Gets if the Material is enabled for use by the features in World.
+     *
+     * @param material Material to check (needs to be an {@link Material#isItem()} or {@link Material#isBlock()})
+     * @param world World to check
+     * @return {@code True} if the Item/Block related to the material is enabled
+     */
+    public boolean isEnabledByFeature(@NotNull Material material, @NotNull World world);
+
+    /**
+     * Gets if the EntityType is enabled for use by the Features in World.
+     *
+     * @param entityType EntityType to check
+     * @param world World to check
+     * @return {@code True} if the type of entity is enabled
+     */
+    public boolean isEnabledByFeature(@NotNull EntityType entityType, @NotNull World world);
+}