Multiple choice technology

Given a method that must ensure that its parameter is not null: 11. public void someMethod(Object value) { 12. // check for null value ... 20. System.out.println(value.getClass()); 21. } What, inserted at line 12, is the appropriate way to handle a null value?

  1. assert value == null;

  2. assert value != null, "value is null";

  3. if (value == null) {throw new AssertionException("value is null");}

  4. if (value == null) {throw new IllegalArgumentException("value is null");}
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

IllegalArgumentException is the standard exception for invalid method arguments. Checking if (value == null) and throwing this exception provides clear error handling and prevents the NullPointerException at line 20. Assertions should not be used for parameter validation as they can be disabled at runtime.

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