It works with dependencies

src/main/java/com/gitlesson/App.java

@@ -1,13 +1,14 @@
 package com.gitlesson;
 
+import com.gitlesson.demolibrary.TestLibrary;
+
 /**
- * Hello world!
+ * Prints the string that gets from TestLibrary!
  *
  */
-public class App 
-{
-    public static void main( String[] args )
-    {
-        System.out.println( "Hello World!" );
+public class App {
+    public static void main(String[] args) {
+        String test = TestLibrary.getText();
+        System.out.print(test);
     }
 }

src/test/java/com/gitlesson/AppTest.java

@@ -1,20 +1,49 @@
 package com.gitlesson;
 
-import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.assertEquals;
 
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
+
+import org.junit.After;
+import org.junit.Before;
 import org.junit.Test;
+import com.gitlesson.demolibrary.TestLibrary;
 
 /**
  * Unit test for simple App.
  */
-public class AppTest 
-{
+public class AppTest {
+    private final PrintStream stardardOut = System.out;
+    private final ByteArrayOutputStream outputStreamCaptor = new ByteArrayOutputStream();
+
+    /**
+     * substitute the standard output with
+     * a new object because we need to check
+     * if the method Main writes the correct string
+     */
+    @Before
+    public void setup() {
+        System.setOut(new PrintStream(outputStreamCaptor));
+    }
+
+    /**
+     * Reset the standard out to the system one
+     */
+    @After
+    public void restore() {
+        System.setOut(stardardOut);
+    }
+
     /**
      * Rigorous Test :-)
      */
     @Test
-    public void shouldAnswerWithTrue()
-    {
-        assertTrue( true );
+    public void shouldAnswerWithTrue() {
+        String[] args = new String[0];
+        App.main(args);
+        String result = outputStreamCaptor.toString();
+        String expected = TestLibrary.getText();
+        assertEquals("This strings should match", expected, result);
     }
 }