How do I make some vanilla blocks unbreakable like bedrock?

[SOLVED]
I've created this event:
 

@SubscribeEvent
	public void onBlockBreaking(PlayerEvent.BreakSpeed event) {
		IBlockState blockstate = event.getState();
		Block block = blockstate.getBlock();
		Item heldItem = event.getEntityPlayer().getHeldItemMainhand().getItem();
		// if instance of  #SOMEBLOCK  
		if(block instanceof BlockStone) {
	           //if holding item instance of #SOMEITEM
			if (!(heldItem instanceof ItemPickaxe))
				//set mining speed to 0
				event.setNewSpeed(0);
		}
	}

Hope this will help someone

Edited November 25, 20177 yr by LavX64

Better idea:

set the block hardness to -1, like bedrock.

 

Its unclear from your post what you are actually trying to achieve.

Edited November 25, 20177 yr by Draco18s

43 minutes ago, Draco18s said:

Better idea:

set the block hardness to -1, like bedrock.

 

Its unclear from your post what you are actually trying to achieve.

I was trying to achieve so I can only mine some blocks with proper tools, sry for my unclearness 

Edited November 25, 20177 yr by LavX64

39 minutes ago, LavX64 said:

I was trying to achieve so I can only mine some blocks with proper tools, sry for my unclearness 

In that case, what you have done is correct.

Mostly.

Instead of if (!(heldItem instanceof ItemPickaxe)) you should use ItemTool#getToolClasses and determine if the item has the pickaxe tool class (think about how you would handle custom tools!).