Minor refactorings and code style changes (#807)

* Made minor changes in some patterns such as removed throws clause where not needed, changed incorrect order of arguments in assertEquals

* Minor refactorings and code style changes. 1) Removed several use of raw types 2) Removed unnecessary throws clauses 3) Used lambda expressions wherever applicable 4) Used apt assertion methods for readability 5) Use of try with resources wherever applicable 6) Corrected incorrect order of assertXXX arguments

* Removed unused import from Promise

* Addressed review comments

* Addressed checkstyle issue

unit-of-work/src/test/java/com/iluwatar/unitofwork/AppTest.java

@@ -33,7 +33,7 @@ import java.io.IOException;
  */
 public class AppTest {
   @Test
-  public void test() throws IOException {
+  public void test() {
     String[] args = {};
     App.main(args);
   }

unit-of-work/src/test/java/com/iluwatar/unitofwork/StudentRepositoryTest.java

@@ -58,7 +58,7 @@ public class StudentRepositoryTest {
   }
 
   @Test
-  public void shouldSaveNewStudentWithoutWritingToDb() throws Exception {
+  public void shouldSaveNewStudentWithoutWritingToDb() {
     studentRepository.registerNew(student1);
     studentRepository.registerNew(student2);
 
@@ -67,7 +67,7 @@ public class StudentRepositoryTest {
   }
 
   @Test
-  public void shouldSaveDeletedStudentWithoutWritingToDb() throws Exception {
+  public void shouldSaveDeletedStudentWithoutWritingToDb() {
     studentRepository.registerDeleted(student1);
     studentRepository.registerDeleted(student2);
 
@@ -76,7 +76,7 @@ public class StudentRepositoryTest {
   }
 
   @Test
-  public void shouldSaveModifiedStudentWithoutWritingToDb() throws Exception {
+  public void shouldSaveModifiedStudentWithoutWritingToDb() {
     studentRepository.registerModified(student1);
     studentRepository.registerModified(student2);
 
@@ -85,7 +85,7 @@ public class StudentRepositoryTest {
   }
 
   @Test
-  public void shouldSaveAllLocalChangesToDb() throws Exception {
+  public void shouldSaveAllLocalChangesToDb() {
     context.put(IUnitOfWork.INSERT, Collections.singletonList(student1));
     context.put(IUnitOfWork.MODIFY, Collections.singletonList(student1));
     context.put(IUnitOfWork.DELETE, Collections.singletonList(student1));
@@ -98,7 +98,7 @@ public class StudentRepositoryTest {
   }
 
   @Test
-  public void shouldNotWriteToDbIfContextIsNull() throws Exception {
+  public void shouldNotWriteToDbIfContextIsNull() {
     StudentRepository studentRepository = new StudentRepository(null, studentDatabase);
 
     studentRepository.commit();
@@ -107,7 +107,7 @@ public class StudentRepositoryTest {
   }
 
   @Test
-  public void shouldNotWriteToDbIfNothingToCommit() throws Exception {
+  public void shouldNotWriteToDbIfNothingToCommit() {
     StudentRepository studentRepository = new StudentRepository(new HashMap<>(), studentDatabase);
 
     studentRepository.commit();
@@ -116,7 +116,7 @@ public class StudentRepositoryTest {
   }
 
   @Test
-  public void shouldNotInsertToDbIfNoRegisteredStudentsToBeCommitted() throws Exception {
+  public void shouldNotInsertToDbIfNoRegisteredStudentsToBeCommitted() {
     context.put(IUnitOfWork.MODIFY, Collections.singletonList(student1));
     context.put(IUnitOfWork.DELETE, Collections.singletonList(student1));
 
@@ -126,7 +126,7 @@ public class StudentRepositoryTest {
   }
 
   @Test
-  public void shouldNotModifyToDbIfNotRegisteredStudentsToBeCommitted() throws Exception {
+  public void shouldNotModifyToDbIfNotRegisteredStudentsToBeCommitted() {
     context.put(IUnitOfWork.INSERT, Collections.singletonList(student1));
     context.put(IUnitOfWork.DELETE, Collections.singletonList(student1));
 
@@ -136,7 +136,7 @@ public class StudentRepositoryTest {
   }
 
   @Test
-  public void shouldNotDeleteFromDbIfNotRegisteredStudentsToBeCommitted() throws Exception {
+  public void shouldNotDeleteFromDbIfNotRegisteredStudentsToBeCommitted() {
     context.put(IUnitOfWork.INSERT, Collections.singletonList(student1));
     context.put(IUnitOfWork.MODIFY, Collections.singletonList(student1));