Question

I have a class such as :

class node 
{
    Integer id ; 
    double lon;
    double lat ; 
    ..... 
}

There is a method in other class takes arguments from node class , and do some operation by them ….
in this method , there is condition like (node1.getId == node2.getId) …

Now I need to give this method node1 , node2 argument where the id of node1 = null ..
when it compares between (node1.getId == node2.getId) , NullpointerException is thrown …

Is there an integer type in Java that I can compare objects of it with null ?? like “int? ” in C# ..

Answer 1

No there is nothing like the ?. If there is a possibility for null, you have to test for it.

So,

if (node1 == null || node2 == null) {
   return false;
}