Hello, i want to make a item that when you shift-right-click a block that implements IWrenchable, it breaks the block, much like the IC2 wrench does with it machines. I have this code in my item class:

public boolean onItemUseFirst(ItemStack stack, EntityPlayer player, World world, int x, int y, int z, int side, float hitX, float hitY, float hitZ)
    {
	if(stack != null && player.isSneaking())
	{
		if(Block.blocksList[world.getBlockId(x, y, z)] instanceof IWrenchable)
		{
			world.spawnEntityInWorld(new EntityItem(world, x, y, z, new ItemStack(Block.blocksList[world.getBlockId(x, y, z)], 1)));
			world.setBlockToAir(x, y, z);
			return true;
		}
	}
        return true;
    }

With that code it will spawn items in the world, but you can't pick them up, and it doesn't break the block. Instead, it's turning invisible. I have used the breakBlock method, but that doesn't work at all.

Any thoughts on how i can do that?

Change things on server side:

if(!world.isRemote){

}

With this code:

 

public boolean onItemUseFirst(ItemStack stack, EntityPlayer player, World world, int x, int y, int z, int side, float hitX, float hitY, float hitZ)
    {
	if(!world.isRemote)
	{
		System.out.println("Doing is server-side!");
		if(stack != null && player.isSneaking())
		{
			System.out.println("I am sneaking!");
			if(Block.blocksList[world.getBlockId(x, y, z)] instanceof IWrenchable)
			{
				System.out.println("It is Wrenchable!");
				world.spawnEntityInWorld(new EntityItem(world, x, y, z, new ItemStack(Block.blocksList[world.getBlockId(x, y, z)], 1)));
				world.setBlockToAir(x, y, z);
				return true;
			}
		}
	}
        return true;
    }

It doesn't break the block. It doesn't even print the lines in the console.

Solved it, i just needed to return false if is could wrench it.