And labels jlabel not have test those components instead need test what added

Output:

The label shall display a random number from 1 to 100 (inclusively).  In the beginning the label shall be empty (no text).

How to test:

This exercise already poses a problem with testing GUIs.  Since the event is generated from Java's event system, it can sometimes be difficult to actually test the particular unit.  For this exercise, since we are using Java's library of components (JFrame(Window), buttons (JButton), and labels (JLabel)) we do not have to test those components.  Instead we need to test what we added, which was a function that randomly generated a number from 1-100 inclusively.  For this exercise your JUnit shall create a PushRandomPanel (with contains JButton and JLabel) and then call the .doClick() on the JButton (which simulates a click) and test that the JLabel's value is correct (call .getText() on the JLabel to get the text.)  Hint: since JLabel is text you will need to first convert to an integer, I suggest using Integer.parseInt(String) function.