Fixed most reported issues by SonarCloud.

unit-of-work/src/main/java/com/iluwatar/unitofwork/IUnitOfWork.java

@@ -29,9 +29,6 @@ package com.iluwatar.unitofwork;
  * @param <T> Any generic entity
  */
 public interface IUnitOfWork<T> {
-  String INSERT = "INSERT";
-  String DELETE = "DELETE";
-  String MODIFY = "MODIFY";
 
   /**
    * Any register new operation occurring on UnitOfWork is only going to be performed on commit.

unit-of-work/src/main/java/com/iluwatar/unitofwork/StudentRepository.java

@@ -52,20 +52,20 @@ public class StudentRepository implements IUnitOfWork<Student> {
   @Override
   public void registerNew(Student student) {
     LOGGER.info("Registering {} for insert in context.", student.getName());
-    register(student, IUnitOfWork.INSERT);
+    register(student, UnitActions.INSERT.getActionValue());
   }
 
   @Override
   public void registerModified(Student student) {
     LOGGER.info("Registering {} for modify in context.", student.getName());
-    register(student, IUnitOfWork.MODIFY);
+    register(student, UnitActions.MODIFY.getActionValue());
 
   }
 
   @Override
   public void registerDeleted(Student student) {
     LOGGER.info("Registering {} for delete in context.", student.getName());
-    register(student, IUnitOfWork.DELETE);
+    register(student, UnitActions.DELETE.getActionValue());
   }
 
   private void register(Student student, String operation) {
@@ -86,21 +86,21 @@ public class StudentRepository implements IUnitOfWork<Student> {
       return;
     }
     LOGGER.info("Commit started");
-    if (context.containsKey(IUnitOfWork.INSERT)) {
+    if (context.containsKey(UnitActions.INSERT.getActionValue())) {
       commitInsert();
     }
 
-    if (context.containsKey(IUnitOfWork.MODIFY)) {
+    if (context.containsKey(UnitActions.MODIFY.getActionValue())) {
       commitModify();
     }
-    if (context.containsKey(IUnitOfWork.DELETE)) {
+    if (context.containsKey(UnitActions.DELETE.getActionValue())) {
       commitDelete();
     }
     LOGGER.info("Commit finished.");
   }
 
   private void commitInsert() {
-    var studentsToBeInserted = context.get(IUnitOfWork.INSERT);
+    var studentsToBeInserted = context.get(UnitActions.INSERT.getActionValue());
     for (var student : studentsToBeInserted) {
       LOGGER.info("Saving {} to database.", student.getName());
       studentDatabase.insert(student);
@@ -108,7 +108,7 @@ public class StudentRepository implements IUnitOfWork<Student> {
   }
 
   private void commitModify() {
-    var modifiedStudents = context.get(IUnitOfWork.MODIFY);
+    var modifiedStudents = context.get(UnitActions.MODIFY.getActionValue());
     for (var student : modifiedStudents) {
       LOGGER.info("Modifying {} to database.", student.getName());
       studentDatabase.modify(student);
@@ -116,7 +116,7 @@ public class StudentRepository implements IUnitOfWork<Student> {
   }
 
   private void commitDelete() {
-    var deletedStudents = context.get(IUnitOfWork.DELETE);
+    var deletedStudents = context.get(UnitActions.DELETE.getActionValue());
     for (var student : deletedStudents) {
       LOGGER.info("Deleting {} to database.", student.getName());
       studentDatabase.delete(student);

unit-of-work/src/main/java/com/iluwatar/unitofwork/UnitActions.java

@@ -0,0 +1,18 @@
+package com.iluwatar.unitofwork;
+
+public enum UnitActions {
+    INSERT("INSERT"),
+    DELETE("DELETE"),
+    MODIFY("MODIFY")
+    ;
+
+    private final String actionValue;
+
+    UnitActions(String actionValue) {
+        this.actionValue = actionValue;
+    }
+
+    public String getActionValue() {
+        return actionValue;
+    }
+}