add assertion about state of stack, and popped element (must follow L…

…IFO)

src/test/Java/TestStack.java

@@ -1,16 +1,16 @@
+import org.junit.Assert;
 import org.junit.Test;
 
 public class TestStack {
-    /**
-     * Currently I don't assert anything. Just look at the console log.
-     */
+
     @Test
     public void testStack() {
         //creating an instance of Stack class
         Stack<Integer> stk= new Stack<>();
 
         // checking stack is empty or not
         boolean result = stk.isEmpty();
+        Assert.assertTrue(result == true);
         System.out.println("Is the stack empty? " + result);
 
         // pushing elements into stack
@@ -23,6 +23,7 @@ public void testStack() {
 
         // remove element at top of the stack
         Integer i = stk.pop();
+        Assert.assertTrue(i == 120);
         System.out.println(String.format("Removing %s ...", i));
         stk.print();