java - How to avoid possible Null Pointer deference -

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i have made simple add method takes 2 args. here code :

public list<mylisttype> add(list<mylisttype> mytypes, mylisttype mytype) {     if (mytypes == null) {         mytypes = new arraylist<mylisttype>();     }      int size = mytypes.size();      if (size > 1) {          boolean laststatus = mytypes.get(mytypes.size()-1).getavailabilitystatus();          boolean secondlastelement = mytypes.get(mytypes.size() - 2).getavailabilitystatus();         if (laststatus == null && secondlastelement == null) {             mytypes.remove(mytypes.size()-1);         }         else if (laststatus.equals(secondlastelement)) {              mytypes.remove(mytypes.size()-1);         }     }      mytypes.add(mytype);      return mytypes; }

i think there possible null pointer deference in if condition, on laststatus. see can in order avoid ?

thanks.

assuming you're using java 7+, can use objects.equals, takes care of both conditions:

boolean secondlastelement = mytypes.get(mytypes.size() - 2).getavailabilitystatus(); if (objects.equals(laststatus, secondlastelement)) {     mytypes.remove(mytypes.size()-1); }

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