Help with making block in 1.15.2 mod

[coxakil50]

I'm starting recently with making simple mod. I add new block but i found problem with adding block item. Can someone help me with that ?

 

This is my code :

in RegistryHandler:

public static final RegistryObject<Item> ROCK_BLOCK_ITEM = Items.register("rock_Block", () -> new BlockItemBase(ROCK_BLOCK.get()));

in BlockItemBase:

public class BlockItemBase extends BlockItem {

 

      public BlockItemBase(Block block) {

              super(block, new Item.Properties().group(CMain.Tab));

     }

}

[coxakil50]

BlockItem gets error and code does not compile.

[coxakil50]

The error is : [14:14:30] [modloading-worker-2/ERROR] [ne.mi.fm.ja.FMLModContainer/LOADING]: Failed to create mod instance. ModID: skysagamod, class com.Destiny.skysagamod.CMain
java.lang.ExceptionInInitializerError: null
    at com.Destiny.skysagamod.CMain.<init>(CMain.java:26) ~[?:?] {re:classloading}
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:1.8.0_181] {}
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[?:1.8.0_181] {}
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[?:1.8.0_181] {}
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[?:1.8.0_181] {}

At this line in CMain class I have :  RegistryHandler.init();

When I add //  in RegistryHandler before public static final RegistryObject<Item> ROCK_BLOCK_ITEM = Items.register("rock_Block", () -> new BlockItemBase(ROCK_BLOCK.get())); code compile so problem is with registration itemblock.