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  1. /* package whatever; // don't place package name! */
  2.  
  3. import java.util.*;
  4. import java.lang.*;
  5. import java.lang.reflect.*;
  6. import java.io.*;
  7.  
  8. /* Name of the class has to be "Main" only if the class is public. */
  9. class Ideone
  10. {
  11. 	public static void main (String[] args) throws java.lang.Exception
  12. 	{
  13. 		Test t = new Test();
  14. 		t.testNull();
  15. 	}
  16. }
  17.  
  18. class Test {
  19. 	private String alpha;
  20. 	private String beta;
  21.  
  22. 	public void testNull() {
  23. 		Field[] fields = getClass().getDeclaredFields(); // get all the fields from your class.
  24. 		for (Field f : fields) {                 // iterate over each field...
  25. 			try {
  26.     			if (f.get(this) == null) {           // evaluate field value.
  27.         			System.out.println(f.getName());
  28.     			}
  29. 			} catch (IllegalArgumentException ex) {
  30. 				ex.printStackTrace();
  31. 			} catch (IllegalAccessException ex) {
  32. 				ex.printStackTrace();
  33. 			}
  34. 		}
  35. 	}
  36. }
Success #stdin #stdout 0.07s 380224KB
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alpha
beta
https://ideone.com/58jSia
language:
Java (HotSpot 12)
created:
9 years ago
visibility:
public

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