FIX:: checkstyle 'common'

src/Common/src/main/java/greenify/common/ApplicationException.java

@@ -1,6 +1,10 @@
 package greenify.common;
 
 public class ApplicationException extends RuntimeException {
+    /**
+     * This method returns an application exception message.
+     * @param message the exception message
+     */
     public ApplicationException(String message) {
         super(message);
     }

src/Common/src/main/java/greenify/common/ErrorResponse.java

@@ -1,18 +1,33 @@
 package greenify.common;
 
 public class ErrorResponse {
-    String message;
+    private String message;
 
+    /**
+     * The method creates a new error response with a message.
+     * @param message the message you want to response with
+     */
     public ErrorResponse(String message) {
         this.message = message;
     }
 
+    /**
+     * This method creates an error response without a message.
+     */
     public ErrorResponse() { }
 
+    /**
+     * This method returns the message.
+     * @return the message
+     */
     public String getMessage() {
         return message;
     }
 
+    /**
+     * This method sets a message.
+     * @param message the message you want set
+     */
     public void setMessage(String message) {
         this.message = message;
     }

src/Common/src/main/java/greenify/common/UserDto.java

@@ -1,9 +1,13 @@
+/*
+  DTO stands for Data Transfer Object.
+  is an object that carries data between processes.
+  The motivation for its use is that communication between processes
+  is usually done
+  resorting to remote interfaces (e.g., web services),
+  where each call is an expensive operation.
+ */
 package greenify.common;
 
-// DTO stands for Data Transfer Object.
-// is an object that carries data between processes.
-// The motivation for its use is that communication between processes is usually done
-// resorting to remote interfaces (e.g., web services), where each call is an expensive operation.
 public class UserDto {
     private Long id;
     private String name;
@@ -21,18 +25,34 @@ public class UserDto {
         this.name = name;
     }
 
+    /**
+     * Method that returns the name of a user.
+     * @return name
+     */
     public String getName() {
         return name;
     }
 
+    /**
+     * Method that sets the name of a user.
+     * @param name name of a user
+     */
     public void setName(String name) {
         this.name = name;
     }
 
+    /**
+     * Method that returns the ID of a user.
+     * @return id
+     */
     public Long getId() {
         return id;
     }
 
+    /**
+     * Method that sets the ID of a user.
+     * @param id id of a user
+     */
     public void setId(Long id) {
         this.id = id;
     }

src/Common/src/test/java/ErrorResponseTest.java

@@ -1,17 +1,15 @@
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-
 import greenify.common.ErrorResponse;
-
 import org.junit.Test;
 
 public class ErrorResponseTest {
+
     @Test
     public void setAndGetTest() {
         ErrorResponse response = new ErrorResponse("New error");
         ErrorResponse testResponse = new ErrorResponse();
         testResponse.setMessage("New error");
-        assertTrue(response.getMessage().equals("New error"));
+        assertEquals("New error", response.getMessage());
     }
 
     @Test
@@ -19,6 +17,6 @@ public class ErrorResponseTest {
         ErrorResponse first = new ErrorResponse("New error");
         ErrorResponse second = new ErrorResponse("New error");
         assertEquals(first.getMessage(), second.getMessage());
-        assertTrue(first.getMessage().equals(second.getMessage()));
     }
+
 }

src/Common/src/test/java/UserDtoTest.java

@@ -1,17 +1,16 @@
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-
 import greenify.common.UserDto;
 import org.junit.Test;
 
 public class UserDtoTest {
+
     @Test
     public void setAndGetTest() {
         UserDto testUser = new UserDto();
         testUser.setId(1L);
         testUser.setName("greenify");
         UserDto user = new UserDto(1L, "greenify");
-        assertTrue(user.getId() == 1L);
+        assertEquals(1L, (long) user.getId());
         assertEquals(user.getName(), "greenify");
     }
 
@@ -22,4 +21,5 @@ public class UserDtoTest {
         assertEquals(first.getId(), second.getId());
         assertEquals(first.getName(), second.getName());
     }
+
 }