java - How to avoid null checking - OOP -


i making game , have tile class contains item. 

public clas tile{     item item;     ....     public void setitem(item item){          this.item = item;     }  }

when have reference tile want call interact() method on item. how can without checking if object null. don't think null object pattern work in scenario because there mixed instance cohesion - subclass of item represent empty item have empty interact() method.

you trying find way not check if object null, when null option.

in case, design check if item != null, before execute item.interact(), not anti-pattern or hacking solution.


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