dependencies: #2449 bump maven-checkstyle-plugin from 3.1.0 to 3.2.0 + resolve chec… (#2464)

* #2449 bump maven-checkstyle-plugin from 3.1.0 to 3.2.0 + resolve checkstyle issues

* remove FileSelectorJFrame.java to resolve checkstyle issue

* remove FileSelectorJFrame.java to resolve checkstyle issue

* remove FileSelectorJFrame.java to resolve checkstyle issue

* add refactored file with correct filename to resolve checkstyle issue

* add the test data

* change filenames from JFrame to Jframe for checkstyle

* fix code smell from  sonar report

* add new testcases to improve the test coverage

* remove code smell

serialized-entity/src/main/java/com/iluwatar/serializedentity/CountryDao.java

@@ -41,6 +41,9 @@ package com.iluwatar.serializedentity;
 
 import java.io.IOException;
 
+/**
+ * DAO interface for Country transactions.
+ */
 public interface CountryDao {
   int insertCountry() throws IOException;
   int selectCountry() throws IOException, ClassNotFoundException;

serialized-entity/src/main/java/com/iluwatar/serializedentity/CountrySchemaSql.java

@@ -33,7 +33,6 @@ import java.sql.Blob;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 import javax.sql.DataSource;
-
 import lombok.extern.slf4j.Slf4j;
 
 /**