BAEL-3700: Add example of uninitialized Mockito annotations

testing-modules/mockito/src/test/java/com/baeldung/mockito/MockitoAnnotationsUninitializedUnitTest.java

@@ -0,0 +1,18 @@
+package com.baeldung.mockito;
+
+import org.junit.Test;
+import org.mockito.Mock;
+import org.mockito.Mockito;
+
+import java.util.List;
+
+public class MockitoAnnotationsUninitializedUnitTest {
+
+    @Mock
+    List<String> mockedList;
+
+    @Test(expected = NullPointerException.class)
+    public void whenMockitoAnnotationsUninitialized_thenNPEThrown() {
+        Mockito.when(mockedList.size()).thenReturn(1);
+    }
+}