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Resolves checkstyle errors for converter, cqrs (#1063)

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* Reduces checkstyle errors in converter

* Reduces checkstyle errors in cqrs
This commit is contained in:
Anurag Agarwal 2019-11-10 22:09:27 +05:30 committed by Ilkka Seppälä
parent 2f49648047
commit 4f9ee0189c
16 changed files with 129 additions and 127 deletions
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7
converter/src/main/java/com/iluwatar/converter/App.java
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@ -23,12 +23,10 @@
package com.iluwatar.converter;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.List;
/**
* The Converter pattern is a behavioral design pattern which allows a common way of bidirectional
* conversion between corresponding types (e.g. DTO and domain representations of the logically
@ -38,8 +36,9 @@ import java.util.List;
public class App {
private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
/**
* Program entry point
* Program entry point.
*
* @param args command line args
*/

31
converter/src/main/java/com/iluwatar/converter/Converter.java
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@ -30,8 +30,9 @@ import java.util.stream.Collectors;
/**
* Generic converter, thanks to Java8 features not only provides a way of generic bidirectional
* conversion between corresponding types, but also a common way of converting a collection of objects
* of the same type, reducing boilerplate code to the absolute minimum.
* conversion between corresponding types, but also a common way of converting a collection of
* objects of the same type, reducing boilerplate code to the absolute minimum.
*
* @param <T> DTO representation's type
* @param <U> Domain representation's type
*/
@ -41,7 +42,9 @@ public class Converter<T, U> {
private final Function<U, T> fromEntity;
/**
* @param fromDto Function that converts given dto entity into the domain entity.
* Constructor.
*
* @param fromDto Function that converts given dto entity into the domain entity.
* @param fromEntity Function that converts given domain entity into the dto entity.
*/
public Converter(final Function<T, U> fromDto, final Function<U, T> fromEntity) {
@ -50,34 +53,44 @@ public class Converter<T, U> {
}
/**
* Converts DTO to Entity.
*
* @param dto DTO entity
* @return The domain representation - the result of the converting function application on dto entity.
* @return The domain representation - the result of the converting function application on dto
* entity.
*/
public final U convertFromDto(final T dto) {
return fromDto.apply(dto);
}
/**
* Converts Entity to DTO.
*
* @param entity domain entity
* @return The DTO representation - the result of the converting function application on domain entity.
* @return The DTO representation - the result of the converting function application on domain
* entity.
*/
public final T convertFromEntity(final U entity) {
return fromEntity.apply(entity);
}
/**
* Converts list of DTOs to list of Entities.
*
* @param dtos collection of DTO entities
* @return List of domain representation of provided entities retrieved by
* mapping each of them with the conversion function
* @return List of domain representation of provided entities retrieved by mapping each of them
* with the conversion function
*/
public final List<U> createFromDtos(final Collection<T> dtos) {
return dtos.stream().map(this::convertFromDto).collect(Collectors.toList());
}
/**
* Converts list of Entities to list of DTOs.
*
* @param entities collection of domain entities
* @return List of domain representation of provided entities retrieved by
* mapping each of them with the conversion function
* @return List of domain representation of provided entities retrieved by mapping each of them
* with the conversion function
*/
public final List<T> createFromEntities(final Collection<U> entities) {
return entities.stream().map(this::convertFromEntity).collect(Collectors.toList());

19
converter/src/main/java/com/iluwatar/converter/User.java
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@ -26,7 +26,7 @@ package com.iluwatar.converter;
import java.util.Objects;
/**
* User class
* User class.
*/
public class User {
private String firstName;
@ -35,10 +35,12 @@ public class User {
private String userId;
/**
* Constructor.
*
* @param firstName user's first name
* @param lastName user's last name
* @param isActive flag indicating whether the user is active
* @param userId user's identificator
* @param userId user's identificator
*/
public User(String firstName, String lastName, boolean isActive, String userId) {
this.firstName = firstName;
@ -63,7 +65,8 @@ public class User {
return userId;
}
@Override public boolean equals(Object o) {
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
@ -72,15 +75,17 @@ public class User {
}
User user = (User) o;
return isActive == user.isActive && Objects.equals(firstName, user.firstName) && Objects
.equals(lastName, user.lastName) && Objects.equals(userId, user.userId);
.equals(lastName, user.lastName) && Objects.equals(userId, user.userId);
}
@Override public int hashCode() {
@Override
public int hashCode() {
return Objects.hash(firstName, lastName, isActive, userId);
}
@Override public String toString() {
@Override
public String toString() {
return "User{" + "firstName='" + firstName + '\'' + ", lastName='" + lastName + '\''
+ ", isActive=" + isActive + ", userId='" + userId + '\'' + '}';
+ ", isActive=" + isActive + ", userId='" + userId + '\'' + '}';
}
}

4
converter/src/main/java/com/iluwatar/converter/UserConverter.java
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@ -33,8 +33,8 @@ public class UserConverter extends Converter<UserDto, User> {
*/
public UserConverter() {
super(userDto -> new User(userDto.getFirstName(), userDto.getLastName(), userDto.isActive(),
userDto.getEmail()),
userDto.getEmail()),
user -> new UserDto(user.getFirstName(), user.getLastName(), user.isActive(),
user.getUserId()));
user.getUserId()));
}
}

18
converter/src/main/java/com/iluwatar/converter/UserDto.java
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@ -23,11 +23,10 @@
package com.iluwatar.converter;
import java.util.Objects;
/**
* User DTO class
* User DTO class.
*/
public class UserDto {
@ -37,6 +36,8 @@ public class UserDto {
private String email;
/**
* Constructor.
*
* @param firstName user's first name
* @param lastName user's last name
* @param isActive flag indicating whether the user is active
@ -65,7 +66,8 @@ public class UserDto {
return email;
}
@Override public boolean equals(Object o) {
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
@ -74,15 +76,17 @@ public class UserDto {
}
UserDto userDto = (UserDto) o;
return isActive == userDto.isActive && Objects.equals(firstName, userDto.firstName) && Objects
.equals(lastName, userDto.lastName) && Objects.equals(email, userDto.email);
.equals(lastName, userDto.lastName) && Objects.equals(email, userDto.email);
}
@Override public int hashCode() {
@Override
public int hashCode() {
return Objects.hash(firstName, lastName, isActive, email);
}
@Override public String toString() {
@Override
public String toString() {
return "UserDto{" + "firstName='" + firstName + '\'' + ", lastName='" + lastName + '\''
+ ", isActive=" + isActive + ", email='" + email + '\'' + '}';
+ ", isActive=" + isActive + ", email='" + email + '\'' + '}';
}
}

50
cqrs/src/main/java/com/iluwatar/cqrs/app/App.java
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@ -23,12 +23,6 @@
package com.iluwatar.cqrs.app;
import java.math.BigInteger;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.iluwatar.cqrs.commandes.CommandServiceImpl;
import com.iluwatar.cqrs.commandes.ICommandService;
import com.iluwatar.cqrs.constants.AppConstants;
@ -37,32 +31,35 @@ import com.iluwatar.cqrs.dto.Book;
import com.iluwatar.cqrs.queries.IQueryService;
import com.iluwatar.cqrs.queries.QueryServiceImpl;
import com.iluwatar.cqrs.util.HibernateUtil;
import java.math.BigInteger;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* CQRS : Command Query Responsibility Segregation. A pattern used to separate query services from commands or writes
* services. The pattern is very simple but it has many consequences. For example, it can be used to tackle down a
* complex domain, or to use other architectures that were hard to implement with the classical way.
*
* This implementation is an example of managing books and authors in a library. The persistence of books and authors is
* done according to the CQRS architecture. A command side that deals with a data model to persist(insert,update,delete)
* objects to a database. And a query side that uses native queries to get data from the database and return objects as
* DTOs (Data transfer Objects).
* CQRS : Command Query Responsibility Segregation. A pattern used to separate query services from
* commands or writes services. The pattern is very simple but it has many consequences. For
* example, it can be used to tackle down a complex domain, or to use other architectures that were
* hard to implement with the classical way.
*
* <p>This implementation is an example of managing books and authors in a library. The persistence
* of books and authors is done according to the CQRS architecture. A command side that deals with a
* data model to persist(insert,update,delete) objects to a database. And a query side that uses
* native queries to get data from the database and return objects as DTOs (Data transfer Objects).
*/
public class App {
private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
/**
* Program entry point
*
* @param args
* command line args
* Program entry point.
*
* @param args command line args
*/
public static void main(String[] args) {
ICommandService commands = new CommandServiceImpl();
// Create Authors and Books using CommandService
commands.authorCreated(AppConstants.E_EVANS, "Eric Evans", "eEvans@email.com");
commands.authorCreated(AppConstants.E_EVANS, "Eric Evans", "evans@email.com");
commands.authorCreated(AppConstants.J_BLOCH, "Joshua Bloch", "jBloch@email.com");
commands.authorCreated(AppConstants.M_FOWLER, "Martin Fowler", "mFowler@email.com");
@ -70,7 +67,8 @@ public class App {
commands.bookAddedToAuthor("Effective Java", 40.54, AppConstants.J_BLOCH);
commands.bookAddedToAuthor("Java Puzzlers", 39.99, AppConstants.J_BLOCH);
commands.bookAddedToAuthor("Java Concurrency in Practice", 29.40, AppConstants.J_BLOCH);
commands.bookAddedToAuthor("Patterns of Enterprise Application Architecture", 54.01, AppConstants.M_FOWLER);
commands.bookAddedToAuthor("Patterns of Enterprise"
+ " Application Architecture", 54.01, AppConstants.M_FOWLER);
commands.bookAddedToAuthor("Domain Specific Languages", 48.89, AppConstants.M_FOWLER);
commands.authorNameUpdated(AppConstants.E_EVANS, "Eric J. Evans");
@ -78,18 +76,18 @@ public class App {
// Query the database using QueryService
Author nullAuthor = queries.getAuthorByUsername("username");
Author eEvans = queries.getAuthorByUsername(AppConstants.E_EVANS);
BigInteger jBlochBooksCount = queries.getAuthorBooksCount(AppConstants.J_BLOCH);
Author evans = queries.getAuthorByUsername(AppConstants.E_EVANS);
BigInteger blochBooksCount = queries.getAuthorBooksCount(AppConstants.J_BLOCH);
BigInteger authorsCount = queries.getAuthorsCount();
Book dddBook = queries.getBook("Domain-Driven Design");
List<Book> jBlochBooks = queries.getAuthorBooks(AppConstants.J_BLOCH);
List<Book> blochBooks = queries.getAuthorBooks(AppConstants.J_BLOCH);
LOGGER.info("Author username : {}", nullAuthor);
LOGGER.info("Author eEvans : {}", eEvans);
LOGGER.info("jBloch number of books : {}", jBlochBooksCount);
LOGGER.info("Author evans : {}", evans);
LOGGER.info("jBloch number of books : {}", blochBooksCount);
LOGGER.info("Number of authors : {}", authorsCount);
LOGGER.info("DDD book : {}", dddBook);
LOGGER.info("jBloch books : {}", jBlochBooks);
LOGGER.info("jBloch books : {}", blochBooks);
HibernateUtil.getSessionFactory().close();
}

11
cqrs/src/main/java/com/iluwatar/cqrs/commandes/CommandServiceImpl.java
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@ -23,17 +23,16 @@
package com.iluwatar.cqrs.commandes;
import com.iluwatar.cqrs.domain.model.Author;
import com.iluwatar.cqrs.domain.model.Book;
import com.iluwatar.cqrs.util.HibernateUtil;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import com.iluwatar.cqrs.domain.model.Author;
import com.iluwatar.cqrs.domain.model.Book;
import com.iluwatar.cqrs.util.HibernateUtil;
/**
* This class is an implementation of {@link ICommandService} interface. It uses Hibernate as an api for persistence.
*
* This class is an implementation of {@link ICommandService} interface. It uses Hibernate as an api
* for persistence.
*/
public class CommandServiceImpl implements ICommandService {

3
cqrs/src/main/java/com/iluwatar/cqrs/commandes/ICommandService.java
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@ -24,8 +24,7 @@
package com.iluwatar.cqrs.commandes;
/**
* This interface represents the commands of the CQRS pattern
*
* This interface represents the commands of the CQRS pattern.
*/
public interface ICommandService {

4
cqrs/src/main/java/com/iluwatar/cqrs/constants/AppConstants.java
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@ -24,9 +24,7 @@
package com.iluwatar.cqrs.constants;
/**
*
* Class to define the constants
*
* Class to define the constants.
*/
public class AppConstants {

13
cqrs/src/main/java/com/iluwatar/cqrs/domain/model/Author.java
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@ -30,7 +30,6 @@ import javax.persistence.Id;
/**
* This is an Author entity. It is used by Hibernate for persistence.
*
*/
@Entity
public class Author {
@ -42,13 +41,11 @@ public class Author {
private String email;
/**
*
* @param username
* username of the author
* @param name
* name of the author
* @param email
* email of the author
* Constructor.
*
* @param username username of the author
* @param name name of the author
* @param email email of the author
*/
public Author(String username, String name, String email) {
this.username = username;

14
cqrs/src/main/java/com/iluwatar/cqrs/domain/model/Book.java
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@ -30,8 +30,8 @@ import javax.persistence.Id;
import javax.persistence.ManyToOne;
/**
* This is a Book entity. It is used by Hibernate for persistence. Many books can be written by one {@link Author}
*
* This is a Book entity. It is used by Hibernate for persistence. Many books can be written by one
* {@link Author}
*/
@Entity
public class Book {
@ -44,13 +44,11 @@ public class Book {
private Author author;
/**
* Constructor.
*
* @param title
* title of the book
* @param price
* price of the book
* @param author
* author of the book
* @param title title of the book
* @param price price of the book
* @param author author of the book
*/
public Book(String title, double price, Author author) {
this.title = title;

19
cqrs/src/main/java/com/iluwatar/cqrs/dto/Author.java
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@ -26,9 +26,7 @@ package com.iluwatar.cqrs.dto;
import java.util.Objects;
/**
*
* This is a DTO (Data Transfer Object) author, contains only useful information to be returned
*
* This is a DTO (Data Transfer Object) author, contains only useful information to be returned.
*/
public class Author {
@ -37,13 +35,11 @@ public class Author {
private String username;
/**
*
* @param name
* name of the author
* @param email
* email of the author
* @param username
* username of the author
* Constructor.
*
* @param name name of the author
* @param email email of the author
* @param username username of the author
*/
public Author(String name, String email, String username) {
this.name = name;
@ -85,7 +81,8 @@ public class Author {
return false;
}
Author other = (Author) obj;
return username.equals(other.getUsername()) && email.equals(other.getEmail()) && name.equals(other.getName());
return username.equals(other.getUsername()) && email.equals(other.getEmail()) && name
.equals(other.getName());
}

13
cqrs/src/main/java/com/iluwatar/cqrs/dto/Book.java
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@ -26,9 +26,7 @@ package com.iluwatar.cqrs.dto;
import java.util.Objects;
/**
*
* This is a DTO (Data Transfer Object) book, contains only useful information to be returned
*
* This is a DTO (Data Transfer Object) book, contains only useful information to be returned.
*/
public class Book {
@ -36,11 +34,10 @@ public class Book {
private double price;
/**
*
* @param title
* title of the book
* @param price
* price of the book
* Constructor.
*
* @param title title of the book
* @param price price of the book
*/
public Book(String title, double price) {
this.title = title;

9
cqrs/src/main/java/com/iluwatar/cqrs/queries/IQueryService.java
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@ -23,16 +23,13 @@
package com.iluwatar.cqrs.queries;
import com.iluwatar.cqrs.dto.Author;
import com.iluwatar.cqrs.dto.Book;
import java.math.BigInteger;
import java.util.List;
import com.iluwatar.cqrs.dto.Author;
import com.iluwatar.cqrs.dto.Book;
/**
*
* This interface represents the query methods of the CQRS pattern
*
* This interface represents the query methods of the CQRS pattern.
*/
public interface IQueryService {

34
cqrs/src/main/java/com/iluwatar/cqrs/queries/QueryServiceImpl.java
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@ -23,23 +23,20 @@
package com.iluwatar.cqrs.queries;
import com.iluwatar.cqrs.constants.AppConstants;
import com.iluwatar.cqrs.dto.Author;
import com.iluwatar.cqrs.dto.Book;
import com.iluwatar.cqrs.util.HibernateUtil;
import java.math.BigInteger;
import java.util.List;
import org.hibernate.SQLQuery;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.transform.Transformers;
import com.iluwatar.cqrs.constants.AppConstants;
import com.iluwatar.cqrs.dto.Author;
import com.iluwatar.cqrs.dto.Book;
import com.iluwatar.cqrs.util.HibernateUtil;
/**
* This class is an implementation of {@link IQueryService}. It uses Hibernate native queries to return DTOs from the
* database.
*
* This class is an implementation of {@link IQueryService}. It uses Hibernate native queries to
* return DTOs from the database.
*/
public class QueryServiceImpl implements IQueryService {
@ -49,11 +46,12 @@ public class QueryServiceImpl implements IQueryService {
public Author getAuthorByUsername(String username) {
Author authorDTo = null;
try (Session session = sessionFactory.openSession()) {
SQLQuery sqlQuery = session
.createSQLQuery("SELECT a.username as \"username\", a.name as \"name\", a.email as \"email\""
+ "FROM Author a where a.username=:username");
SQLQuery sqlQuery = session.createSQLQuery("SELECT a.username as \"username\","
+ " a.name as \"name\", a.email as \"email\""
+ "FROM Author a where a.username=:username");
sqlQuery.setParameter(AppConstants.USER_NAME, username);
authorDTo = (Author) sqlQuery.setResultTransformer(Transformers.aliasToBean(Author.class)).uniqueResult();
authorDTo = (Author) sqlQuery.setResultTransformer(Transformers.aliasToBean(Author.class))
.uniqueResult();
}
return authorDTo;
}
@ -62,10 +60,11 @@ public class QueryServiceImpl implements IQueryService {
public Book getBook(String title) {
Book bookDTo = null;
try (Session session = sessionFactory.openSession()) {
SQLQuery sqlQuery = session
.createSQLQuery("SELECT b.title as \"title\", b.price as \"price\"" + " FROM Book b where b.title=:title");
SQLQuery sqlQuery = session.createSQLQuery("SELECT b.title as \"title\","
+ " b.price as \"price\"" + " FROM Book b where b.title=:title");
sqlQuery.setParameter("title", title);
bookDTo = (Book) sqlQuery.setResultTransformer(Transformers.aliasToBean(Book.class)).uniqueResult();
bookDTo =
(Book) sqlQuery.setResultTransformer(Transformers.aliasToBean(Book.class)).uniqueResult();
}
return bookDTo;
}
@ -87,7 +86,8 @@ public class QueryServiceImpl implements IQueryService {
BigInteger bookcount = null;
try (Session session = sessionFactory.openSession()) {
SQLQuery sqlQuery = session.createSQLQuery(
"SELECT count(b.title)" + " FROM Book b, Author a where b.author_id = a.id and a.username=:username");
"SELECT count(b.title)" + " FROM Book b, Author a"
+ " where b.author_id = a.id and a.username=:username");
sqlQuery.setParameter(AppConstants.USER_NAME, username);
bookcount = (BigInteger) sqlQuery.uniqueResult();
}

7
cqrs/src/main/java/com/iluwatar/cqrs/util/HibernateUtil.java
View File

@ -31,8 +31,8 @@ import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* This class simply returns one instance of {@link SessionFactory} initialized when the application is started
*
* This class simply returns one instance of {@link SessionFactory} initialized when the application
* is started.
*/
public class HibernateUtil {
@ -42,7 +42,8 @@ public class HibernateUtil {
private static SessionFactory buildSessionFactory() {
// configures settings from hibernate.cfg.xml
final StandardServiceRegistry registry = new StandardServiceRegistryBuilder().configure().build();
final StandardServiceRegistry registry =
new StandardServiceRegistryBuilder().configure().build();
try {
return new MetadataSources(registry).buildMetadata().buildSessionFactory();
} catch (Exception ex) {