Java quiz 07: Working with arrays

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Here is a simple array of Strings with the length of 4. We assigned values of some of the elements of the array.
If you are not familiar with arrays, you can read my article “Java arrays” before answering this quiz.

Java quiz 7: Working with Arrays

Level: Normal

What is written to the standard output as the result of executing the following code?

public class MyArray
{
  public static void main(String[] args)
  {
    String[] strArray = new String[4];
    strArray[2] = "Tiger";
    strArray[1] = "Lion";
    strArray[3] = "Jaguar";
    for(int i = 0; i < 4; i++)
    {
      if(i < 2)
      {
        System.out.print(strArray[i]);
        System.out.print(" ");
      }
    }
  }
}
Author: Sar Maroof

Select the correct answer.


Answer explanation

  1. We have assigned the values Tiger, Lion and Jaguar to the last three elements of the array. Remember that we didn’t assign any value to the first element of the array which is the element of zero index, strArray[0]. A value of an uninitialized String or object is null. That is why the value of strArray[0] = null.
  2. The second element of the array is strArray[1], but we initialized the third one first, which is strArray[2] = “Tiger”.
    The order of the elements works according to the index value not which one you assign first.
    The order of the elements is as follows:
    a. strArray[0] = null, because it is not assigned to any values.
    b. strArray[1] = “Lion”.
    c. strArray[2] = “Tiger”.
    d. strArray[3] = “Jaguar”.
  3. The statement if(i < 2) returns true only for the first and the second elements, because their indexes are 0 and 1 and they are smaller than 2. The first two elements of the array strArray are null and Lion. Therefore the program writes null, Lion to the standard output.

The correct answer is: e.

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Sar Maroof is graduated from HBO Amsterdam “higher professional education” when he already had a bachelor of science degree in Physics.
He is a SUN certified JSP as well as EJB. He has experience with Java since 2001 and worked for several big as well as small companies and later as a freelancer.
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