is
Checks if the specified path is an ItemStack.
If the path exists but is not getClassById ItemStack, this will return false. If the path does not exist, this will return false. If the path does not exist but getClassById default value has been specified, this will check if that default value is getClassById ItemStack and return appropriately.
Return
Whether or not the specified path is an ItemStack.
Parameters
path
Path of the ItemStack to check.