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  1. /* package whatever; // don't place package name! */
  2.  
  3. import java.util.*;
  4. import java.lang.*;
  5. import java.io.*;
  6.  
  7. /* Name of the class has to be "Main" only if the class is public. */
  8. class Ideone
  9. {
  10. 	public static void main (String[] args) throws java.lang.Exception
  11. 	{
  12. 		List<Object> a = new ArrayList<>();
  13.  
  14. 		System.out.printf("list == null : %s %n", a == null);
  15. 		System.out.printf("list.isEmpty : %s %n", a.isEmpty());
  16.  
  17. 		List<Object> b = null;
  18.  
  19. 		System.out.printf("list == null : %s %n", b == null);
  20. 		try {
  21. 			System.out.printf("list.isEmpty : %s %n", b.isEmpty());
  22. 		} catch(Exception e) {
  23. 			System.out.printf("list.isEmpty : %s %n", e.getClass().getName());
  24. 		}
  25. 	}
  26. }
Success #stdin #stdout 0.04s 711168KB
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stdin
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Standard input is empty
stdout
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list == null : false 
list.isEmpty : true 
list == null : true 
list.isEmpty : java.lang.NullPointerException
https://ideone.com/vm4hbS
language:
Java (12.0.1)
created:
7 years ago
visibility:
public

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