[1.11.2 Eclipse Method getRegistryName and getUnlocalizedName are undefined]

I'm new with modding and I wanted to create a Item. Now,  this is my Item Class

ItemObsidianingot

package items;

import com.FlinnX.MoreMaterials.Reference;
import net.minecraft.item.Item;

public class ItemObsidianingot extends Item {

	public ItemObsidianingot() {
		setUnlocalizedName(Reference.MoreMaterialsItems.OBSIDIANINGOT.getUnlocalizedName());
		setRegistryName(Reference.MoreMaterialsItems.OBSIDIANINGOT.getRegistryName());
	}
}

 

And this is my References Class

package com.FlinnX.MoreMaterials;

public class Reference {

	//Fundemental Mod Variables
	public static final String MOD_ID = "fmm"; //ID of the Mod: FlinnxMOreMAterials
	public static final String NAME = "More Materials Mod"; //The Name
	public static final String VERSION = "0.1-alpha"; //The Version of the Mod
	public static final String ACCEPTED_VERSIONS = "[1.11.2]"; //The Version it will be playable on
	
	public static final String CLIENT_PROXY_CLASS = "com.FlinnX.MoreMaterials.proxy.ClientProxy"; //Client Proxy Location
	public static final String SERVER_PROXY_CLASS = "com.FlinnX.MoreMaterials.proxy.ServerProxy"; //Server Proxy Location
	
	
	public static enum MoreMaterialsItems {
		OBSIDIANINGOT("obsidianingot", "ItemObsidianingot");
		
		private String unlocalizedName;
		private String registryName;
		
		MoreMaterialsItems(String unlocalizedName, String registryName) {
			this.unlocalizedName = unlocalizedName;
			this.registryName = registryName;
		}
	}
}

 

This is my Error:

 

The method getRegistryName() is undefined for the type Reference.MoreMaterialsItems

The method getUnlocalizedName() is undefined for the type Reference.MoreMaterilasItems

 

I saw that another user had this error and someone suggested that he should rename the enum. I tried this out too but it didn't worked.