SPIGOT-7195, SPIGOT-7197: Add DataPack API

By: Doc <nachito94@msn.com>

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

@@ -0,0 +1,107 @@
+package org.bukkit.packs;
+
+import java.util.Set;
+import org.bukkit.FeatureFlag;
+import org.bukkit.Keyed;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Represents a data pack.
+ */
+@ApiStatus.Experimental
+public interface DataPack extends Keyed {
+
+    /**
+     * Gets the title of the data pack.
+     *
+     * @return the title
+     */
+    @NotNull
+    public String getTitle();
+
+    /**
+     * Gets the description of the data pack.
+     *
+     * @return the description
+     */
+    @NotNull
+    public String getDescription();
+
+    /**
+     * Gets the pack version.
+     * <br>
+     * This is related to the server version to work.
+     *
+     * @return the pack version
+     */
+    public int getPackFormat();
+
+    /**
+     * Gets if the data pack is enabled on the server.
+     *
+     * @return True if is enabled
+     */
+    public boolean isEnabled();
+
+    /**
+     * Gets if the data pack is required on the server.
+     *
+     * @return True if is required
+     */
+    public boolean isRequired();
+
+    /**
+     * Gets the compatibility of this data pack with the server.
+     *
+     * @return an enum
+     */
+    @NotNull
+    public Compatibility getCompatibility();
+
+    /**
+     * Gets a set of features requested by this data pack.
+     *
+     * @return a set of features
+     */
+    @NotNull
+    public Set<FeatureFlag> getRequestedFeatures();
+
+    /**
+     * Gets the source of this data pack.
+     *
+     * @return the source
+     */
+    @NotNull
+    public Source getSource();
+
+    /**
+     * Show the compatibility of the data pack with the server.
+     */
+    public enum Compatibility {
+
+        /**
+         * It's newer than the server pack version.
+         */
+        NEW,
+        /**
+         * It's older than the server pack version.
+         */
+        OLD,
+        /**
+         * Its compatible with the server pack version.
+         */
+        COMPATIBLE;
+    }
+
+    /**
+     * Represent the source of a data pack.
+     */
+    public enum Source {
+        DEFAULT,
+        BUILT_IN,
+        FEATURE,
+        WORLD,
+        SERVER;
+    }
+}