#590 add explanation for DTO

data-transfer-object/src/main/java/com/iluwatar/datatransfer/App.java

@@ -32,15 +32,15 @@ import org.slf4j.LoggerFactory;
  * The Data Transfer Object pattern is a design pattern in which an data transfer object is used to
  * serve related information together to avoid multiple call for each piece of information.
  *
- * <p>In this example, ({@link CustomerClientApp}) as as customer details consumer i.e. client to
+ * <p>In this example, ({@link App}) as as customer details consumer i.e. client to
  * request for customer details to server.
  *
  * <p>CustomerResource ({@link CustomerResource}) act as server to serve customer information. And
  * The CustomerDto ({@link CustomerDto} is data transfer object to share customer information.
  */
-public class CustomerClientApp {
+public class App {
 
-  private static final Logger LOGGER = LoggerFactory.getLogger(CustomerClientApp.class);
+  private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
 
   /**
    * Method as act client and request to server for details.

data-transfer-object/src/test/java/com/iluwatar/datatransfer/AppTest.java

@@ -0,0 +1,33 @@
+/*
+ * The MIT License
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package com.iluwatar.datatransfer;
+
+import org.junit.jupiter.api.Test;
+
+public class AppTest {
+    @Test
+    public void test() throws Exception {
+        App.main(new String[]{});
+    }
+}