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Problem :

Everytime we compile the GUI , we get bellow error

exception in thread "javafx application thread" java.lang.nullpointerexception

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6,930 points

1 Answer

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My advise would be to never initialize variable at the declaration, but do it in constructor, and then check for every nullity possible.

Please refer bellow code:

public class MyClass{

double mycrashRisk;

public MyClass(){
 TDriver id = ...//get id
 if(id == null){
   throw new MyExplicitException();
 mycrashRisk = mycalcRisk(id);

Further Readings:


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