feat(api): IObjectHolder

src/main/java/org/auioc/mcmod/arnicalib/api/java/holder/IObjectHolder.java

@@ -0,0 +1,9 @@
+package org.auioc.mcmod.arnicalib.api.java.holder;
+
+public interface IObjectHolder<T> {
+
+    T get();
+
+    void set(T value);
+
+}

src/main/java/org/auioc/mcmod/arnicalib/api/java/holder/ObjectHolder.java

@@ -1,17 +1,19 @@
 package org.auioc.mcmod.arnicalib.api.java.holder;
 
-public class ObjectHolder<T> {
+public class ObjectHolder<T> implements IObjectHolder<T> {
 
     protected T value;
 
     public ObjectHolder(T value) {
         this.value = value;
     }
 
+    @Override
     public T get() {
         return this.value;
     }
 
+    @Override
     public void set(T value) {
         this.value = value;
     }