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Java StackTrace does not show where is the actual null in the line

The following Exception:

Exception in thread "main" java.lang.NullPointerException
at javaapplication7.App.main(App.java:8)
Java Result: 1

thrown from code:

Object o = n1.getObj().getObj().getObj().getObj();

So from the stack trace it is not clear which element was actually null. Is there a method to find it out without debugging? Maybe some other JVM will do?

Solution

  • No, you can't figure out which of the callees in 

    Object o = obj.getObj().getObj().getObj().getObj();

    causes the NullPointerException by looking at the stack trace. It is often recommended to format your code as

    Object o = obj.getObj()
              .getObj()
              .getObj()
              .getObj();

    for this reason.