JAVA-2432: Moved 5 articles to spring-data-jpa-query-2

2020-09-28 23:17:31 +05:30
parent 7de65d1211
commit 2dd77a259d
91 changed files with 3681 additions and 141 deletions
@@ -6,6 +6,12 @@ This module contains articles about querying data using Spring Data JPA
 - [Spring Data JPA @Query Annotation](https://www.baeldung.com/spring-data-jpa-query)
 - [Use Criteria Queries in a Spring Data Application](https://www.baeldung.com/spring-data-criteria-queries)
 - [Query Entities by Dates and Times with Spring Data JPA](https://www.baeldung.com/spring-data-jpa-query-by-date)
+- [Hibernate Pagination](https://www.baeldung.com/hibernate-pagination)
+- [Sorting with Hibernate](https://www.baeldung.com/hibernate-sort)
+- [Stored Procedures with Hibernate](https://www.baeldung.com/stored-procedures-with-hibernate-tutorial)
+- [Eager/Lazy Loading In Hibernate](https://www.baeldung.com/hibernate-lazy-eager-loading)
+- [Auditing with JPA, Hibernate, and Spring Data JPA](https://www.baeldung.com/database-auditing-jpa)
+
 - More articles: [[<-- prev]](../spring-data-jpa-query)

 ### Eclipse Config 
@@ -18,6 +18,10 @@
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
+        <dependency>
+            <groupId>org.springframework.security</groupId>
+            <artifactId>spring-security-core</artifactId>
+        </dependency>

        <dependency>
            <groupId>com.h2database</groupId>
@@ -28,6 +32,55 @@
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
        </dependency>
+        
+        <dependency>
+            <groupId>org.hibernate</groupId>
+            <artifactId>hibernate-envers</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>javax.transaction</groupId>
+            <artifactId>jta</artifactId>
+            <version>${jta.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>mysql</groupId>
+            <artifactId>mysql-connector-java</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.google.guava</groupId>
+            <artifactId>guava</artifactId>
+            <version>${guava.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.tomcat</groupId>
+            <artifactId>tomcat-dbcp</artifactId>
+            <version>${tomcat-dbcp.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.hibernate</groupId>
+            <artifactId>hibernate-core</artifactId>
+            <version>${hibernate.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.hibernate</groupId>
+            <artifactId>hibernate-envers</artifactId>
+            <version>${hibernate.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-test</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.security</groupId>
+            <artifactId>spring-security-test</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.hsqldb</groupId>
+            <artifactId>hsqldb</artifactId>
+            <scope>test</scope>
+        </dependency>
    </dependencies>

    <properties>
@@ -35,5 +88,10 @@
        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
        <junit-jupiter.version>5.6.2</junit-jupiter.version>
        <junit.version>4.13</junit.version>
+        <tomcat-dbcp.version>9.0.0.M26</tomcat-dbcp.version>
+        <jta.version>1.1</jta.version>
+        <guava.version>21.0</guava.version>
+        <!-- persistence -->
+        <hibernate.version>5.2.10.Final</hibernate.version>
    </properties>
 </project>
@@ -0,0 +1,186 @@
+package com.baeldung.config;
+
+import java.util.Properties;
+
+import javax.sql.DataSource;
+
+import org.apache.tomcat.dbcp.dbcp2.BasicDataSource;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.PropertySource;
+import org.springframework.core.env.Environment;
+import org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor;
+import org.springframework.data.domain.AuditorAware;
+import org.springframework.data.jpa.repository.config.EnableJpaAuditing;
+import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
+import org.springframework.orm.hibernate5.HibernateTransactionManager;
+import org.springframework.orm.hibernate5.LocalSessionFactoryBean;
+import org.springframework.orm.jpa.JpaTransactionManager;
+import org.springframework.orm.jpa.JpaVendorAdapter;
+import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
+import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
+import org.springframework.transaction.PlatformTransactionManager;
+import org.springframework.transaction.annotation.EnableTransactionManagement;
+
+import com.baeldung.hibernate.audit.AuditorAwareImpl;
+import com.baeldung.persistence.dao.IBarAuditableDao;
+import com.baeldung.persistence.dao.IBarDao;
+import com.baeldung.persistence.dao.IFooAuditableDao;
+import com.baeldung.persistence.dao.IFooDao;
+import com.baeldung.persistence.dao.impl.BarAuditableDao;
+import com.baeldung.persistence.dao.impl.BarDao;
+import com.baeldung.persistence.dao.impl.BarJpaDao;
+import com.baeldung.persistence.dao.impl.FooAuditableDao;
+import com.baeldung.persistence.dao.impl.FooDao;
+import com.baeldung.persistence.service.IBarAuditableService;
+import com.baeldung.persistence.service.IBarService;
+import com.baeldung.persistence.service.IFooAuditableService;
+import com.baeldung.persistence.service.IFooService;
+import com.baeldung.persistence.service.impl.BarAuditableService;
+import com.baeldung.persistence.service.impl.BarJpaService;
+import com.baeldung.persistence.service.impl.BarSpringDataJpaService;
+import com.baeldung.persistence.service.impl.FooAuditableService;
+import com.baeldung.persistence.service.impl.FooService;
+import com.google.common.base.Preconditions;
+
+@Configuration
+@EnableTransactionManagement
+@EnableJpaRepositories(basePackages = { "com.baeldung.persistence" }, transactionManagerRef = "jpaTransactionManager", entityManagerFactoryRef = "jpaEntityManager")
+@EnableJpaAuditing(auditorAwareRef = "auditorProvider")
+@PropertySource({ "classpath:persistence-h2.properties" })
+@ComponentScan({ "com.baeldung.persistence" })
+public class PersistenceConfig {
+
+    @Autowired
+    private Environment env;
+
+    public PersistenceConfig() {
+        super();
+    }
+
+    @Bean("auditorProvider")
+    public AuditorAware<String> auditorProvider() {
+        return new AuditorAwareImpl();
+    }
+    
+    @Bean
+    public LocalSessionFactoryBean sessionFactory() {
+        final LocalSessionFactoryBean sessionFactory = new LocalSessionFactoryBean();
+        sessionFactory.setDataSource(restDataSource());
+        sessionFactory.setPackagesToScan(new String[] { "com.baeldung.persistence.model" });
+        sessionFactory.setHibernateProperties(hibernateProperties());
+
+        return sessionFactory;
+    }
+
+    @Bean("jpaEntityManager")
+    public LocalContainerEntityManagerFactoryBean entityManagerFactory() {
+        final LocalContainerEntityManagerFactoryBean emf = new LocalContainerEntityManagerFactoryBean();
+        emf.setDataSource(restDataSource());
+        emf.setPackagesToScan(new String[] { "com.baeldung.persistence.model" });
+
+        final JpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
+        emf.setJpaVendorAdapter(vendorAdapter);
+        emf.setJpaProperties(hibernateProperties());
+
+        return emf;
+    }
+
+    @Bean
+    public DataSource restDataSource() {
+        final BasicDataSource dataSource = new BasicDataSource();
+        dataSource.setDriverClassName(Preconditions.checkNotNull(env.getProperty("jdbc.driverClassName")));
+        dataSource.setUrl(Preconditions.checkNotNull(env.getProperty("jdbc.url")));
+        dataSource.setUsername(Preconditions.checkNotNull(env.getProperty("jdbc.user")));
+        dataSource.setPassword(Preconditions.checkNotNull(env.getProperty("jdbc.pass")));
+
+        return dataSource;
+    }
+
+    @Bean
+    public PlatformTransactionManager hibernateTransactionManager() {
+        final HibernateTransactionManager transactionManager = new HibernateTransactionManager();
+        transactionManager.setSessionFactory(sessionFactory().getObject());
+        return transactionManager;
+    }
+
+    @Bean
+    public PlatformTransactionManager jpaTransactionManager() {
+        final JpaTransactionManager transactionManager = new JpaTransactionManager();
+        transactionManager.setEntityManagerFactory(entityManagerFactory().getObject());
+        return transactionManager;
+    }
+
+    @Bean
+    public PersistenceExceptionTranslationPostProcessor exceptionTranslation() {
+        return new PersistenceExceptionTranslationPostProcessor();
+    }
+
+    @Bean
+    public IBarService barJpaService() {
+        return new BarJpaService();
+    }
+
+    @Bean
+    public IBarService barSpringDataJpaService() {
+        return new BarSpringDataJpaService();
+    }
+
+    @Bean
+    public IFooService fooHibernateService() {
+        return new FooService();
+    }
+
+    @Bean
+    public IBarAuditableService barHibernateAuditableService() {
+        return new BarAuditableService();
+    }
+
+    @Bean
+    public IFooAuditableService fooHibernateAuditableService() {
+        return new FooAuditableService();
+    }
+
+    @Bean
+    public IBarDao barJpaDao() {
+        return new BarJpaDao();
+    }
+
+    @Bean
+    public IBarDao barHibernateDao() {
+        return new BarDao();
+    }
+
+    @Bean
+    public IBarAuditableDao barHibernateAuditableDao() {
+        return new BarAuditableDao();
+    }
+
+    @Bean
+    public IFooDao fooHibernateDao() {
+        return new FooDao();
+    }
+
+    @Bean
+    public IFooAuditableDao fooHibernateAuditableDao() {
+        return new FooAuditableDao();
+    }
+
+    private final Properties hibernateProperties() {
+        final Properties hibernateProperties = new Properties();
+        hibernateProperties.setProperty("hibernate.hbm2ddl.auto", env.getProperty("hibernate.hbm2ddl.auto"));
+        hibernateProperties.setProperty("hibernate.dialect", env.getProperty("hibernate.dialect"));
+
+        hibernateProperties.setProperty("hibernate.show_sql", "true");
+        // hibernateProperties.setProperty("hibernate.format_sql", "true");
+        // hibernateProperties.setProperty("hibernate.globally_quoted_identifiers", "true");
+
+        // Envers properties
+        hibernateProperties.setProperty("org.hibernate.envers.audit_table_suffix", env.getProperty("envers.audit_table_suffix"));
+
+        return hibernateProperties;
+    }
+
+}
@@ -0,0 +1,18 @@
+package com.baeldung.config;
+
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.ImportResource;
+import org.springframework.transaction.annotation.EnableTransactionManagement;
+
+@Configuration
+@EnableTransactionManagement
+@ComponentScan({ "com.baeldung.persistence.dao", "com.baeldung.persistence.service" })
+@ImportResource({ "classpath:hibernate4Config.xml" })
+public class PersistenceXmlConfig {
+
+    public PersistenceXmlConfig() {
+        super();
+    }
+
+}
@@ -0,0 +1,18 @@
+package com.baeldung.hibernate.audit;
+
+import java.util.Optional;
+
+import org.springframework.data.domain.AuditorAware;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.context.SecurityContextHolder;
+
+public class AuditorAwareImpl implements AuditorAware<String> {
+
+    @Override
+    public Optional<String> getCurrentAuditor() {
+        return Optional.ofNullable(SecurityContextHolder.getContext())
+            .map(e -> e.getAuthentication())
+            .map(Authentication::getName);
+    }
+
+}
@@ -0,0 +1,58 @@
+package com.baeldung.hibernate.fetching.model;
+
+import javax.persistence.*;
+import java.io.Serializable;
+import java.sql.Date;
+
+@Entity
+@Table(name = "USER_ORDER")
+public class OrderDetail implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    @Id
+    @GeneratedValue
+    @Column(name = "ORDER_ID")
+    private Long orderId;
+
+    public OrderDetail() {
+    }
+
+    public OrderDetail(Date orderDate, String orderDesc) {
+        super();
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + ((orderId == null) ? 0 : orderId.hashCode());
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj)
+            return true;
+        if (obj == null)
+            return false;
+        if (getClass() != obj.getClass())
+            return false;
+        OrderDetail other = (OrderDetail) obj;
+        if (orderId == null) {
+            if (other.orderId != null)
+                return false;
+        } else if (!orderId.equals(other.orderId))
+            return false;
+
+        return true;
+    }
+
+    public Long getOrderId() {
+        return orderId;
+    }
+
+    public void setOrderId(Long orderId) {
+        this.orderId = orderId;
+    }
+}
@@ -0,0 +1,71 @@
+package com.baeldung.hibernate.fetching.model;
+
+import javax.persistence.*;
+import java.io.Serializable;
+import java.util.HashSet;
+import java.util.Set;
+
+@Entity
+@Table(name = "USER")
+public class UserEager implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    @Id
+    @GeneratedValue
+    @Column(name = "USER_ID")
+    private Long userId;
+
+    @OneToMany(fetch = FetchType.EAGER)
+    private Set<OrderDetail> orderDetail = new HashSet();
+
+    public UserEager() {
+    }
+
+    public UserEager(final Long userId) {
+        super();
+        this.userId = userId;
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + ((userId == null) ? 0 : userId.hashCode());
+        return result;
+    }
+
+    @Override
+    public boolean equals(final Object obj) {
+        if (this == obj)
+            return true;
+        if (obj == null)
+            return false;
+        if (getClass() != obj.getClass())
+            return false;
+        final UserEager other = (UserEager) obj;
+        if (userId == null) {
+            if (other.userId != null)
+                return false;
+        } else if (!userId.equals(other.userId))
+            return false;
+        return true;
+    }
+
+    public Long getUserId() {
+        return userId;
+    }
+
+    public void setUserId(final Long userId) {
+        this.userId = userId;
+    }
+
+    public Set<OrderDetail> getOrderDetail() {
+        return orderDetail;
+    }
+
+    public void setOrderDetail(Set<OrderDetail> orderDetail) {
+        this.orderDetail = orderDetail;
+    }
+
+}
@@ -0,0 +1,71 @@
+package com.baeldung.hibernate.fetching.model;
+
+import javax.persistence.*;
+import java.io.Serializable;
+import java.util.HashSet;
+import java.util.Set;
+
+@Entity
+@Table(name = "USER")
+public class UserLazy implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    @Id
+    @GeneratedValue
+    @Column(name = "USER_ID")
+    private Long userId;
+
+    @OneToMany(fetch = FetchType.LAZY)
+    private Set<OrderDetail> orderDetail = new HashSet();
+
+    public UserLazy() {
+    }
+
+    public UserLazy(final Long userId) {
+        super();
+        this.userId = userId;
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + ((userId == null) ? 0 : userId.hashCode());
+        return result;
+    }
+
+    @Override
+    public boolean equals(final Object obj) {
+        if (this == obj)
+            return true;
+        if (obj == null)
+            return false;
+        if (getClass() != obj.getClass())
+            return false;
+        final UserLazy other = (UserLazy) obj;
+        if (userId == null) {
+            if (other.userId != null)
+                return false;
+        } else if (!userId.equals(other.userId))
+            return false;
+        return true;
+    }
+
+    public Long getUserId() {
+        return userId;
+    }
+
+    public void setUserId(final Long userId) {
+        this.userId = userId;
+    }
+
+    public Set<OrderDetail> getOrderDetail() {
+        return orderDetail;
+    }
+
+    public void setOrderDetail(Set<OrderDetail> orderDetail) {
+        this.orderDetail = orderDetail;
+    }
+
+}
@@ -0,0 +1,29 @@
+package com.baeldung.hibernate.fetching.util;
+
+import org.hibernate.Session;
+import org.hibernate.SessionFactory;
+import org.hibernate.cfg.Configuration;
+
+public class HibernateUtil {
+
+    @SuppressWarnings("deprecation")
+    public static Session getHibernateSession(String fetchMethod) {
+        // two config files are there
+        // one with lazy loading enabled
+        // another lazy = false
+        SessionFactory sf;
+        if ("lazy".equals(fetchMethod)) {
+            sf = new Configuration().configure("fetchingLazy.cfg.xml").buildSessionFactory();
+        } else {
+            sf = new Configuration().configure("fetching.cfg.xml").buildSessionFactory();
+        }
+
+        // fetching.cfg.xml is used for this example
+        return sf.openSession();
+    }
+
+    public static Session getHibernateSession() {
+        return new Configuration().configure("fetching.cfg.xml").buildSessionFactory().openSession();
+    }
+
+}
@@ -0,0 +1,68 @@
+package com.baeldung.hibernate.fetching.view;
+
+import com.baeldung.hibernate.fetching.model.OrderDetail;
+import com.baeldung.hibernate.fetching.model.UserEager;
+import com.baeldung.hibernate.fetching.model.UserLazy;
+import com.baeldung.hibernate.fetching.util.HibernateUtil;
+import org.hibernate.Session;
+import org.hibernate.Transaction;
+
+import java.util.List;
+import java.util.Set;
+
+public class FetchingAppView {
+
+    public FetchingAppView() {
+
+    }
+
+    // lazily loaded
+    public Set<OrderDetail> lazyLoaded() {
+        final Session sessionLazy = HibernateUtil.getHibernateSession("lazy");
+        List<UserLazy> users = sessionLazy.createQuery("From UserLazy").list();
+        UserLazy userLazyLoaded = users.get(0);
+        // since data is lazyloaded so data won't be initialized
+        return (userLazyLoaded.getOrderDetail());
+    }
+
+    // eagerly loaded
+    public Set<OrderDetail> eagerLoaded() {
+        final Session sessionEager = HibernateUtil.getHibernateSession();
+        // data should be loaded in the following line
+        // also note the queries generated
+        List<UserEager> user = sessionEager.createQuery("From UserEager").list();
+        UserEager userEagerLoaded = user.get(0);
+        return userEagerLoaded.getOrderDetail();
+    }
+
+    // creates test data
+    // call this method to create the data in the database
+    public void createTestData() {
+
+        final Session session = HibernateUtil.getHibernateSession("lazy");
+        Transaction tx = session.beginTransaction();
+        final UserLazy user1 = new UserLazy();
+        final UserLazy user2 = new UserLazy();
+        final UserLazy user3 = new UserLazy();
+
+        session.save(user1);
+        session.save(user2);
+        session.save(user3);
+
+        final OrderDetail order1 = new OrderDetail();
+        final OrderDetail order2 = new OrderDetail();
+        final OrderDetail order3 = new OrderDetail();
+        final OrderDetail order4 = new OrderDetail();
+        final OrderDetail order5 = new OrderDetail();
+
+        session.saveOrUpdate(order1);
+        session.saveOrUpdate(order2);
+        session.saveOrUpdate(order3);
+        session.saveOrUpdate(order4);
+        session.saveOrUpdate(order5);
+
+        tx.commit();
+        session.close();
+
+    }
+}
@@ -1,9 +0,0 @@
-package com.baeldung.persistence.dao;
-
-import com.baeldung.persistence.model.Book;
-import org.springframework.data.jpa.repository.JpaRepository;
-import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
-
-public interface BookRepository extends JpaRepository<Book, Long>, BookRepositoryCustom, JpaSpecificationExecutor<Book> {
-
-}
@@ -1,11 +0,0 @@
-package com.baeldung.persistence.dao;
-
-import com.baeldung.persistence.model.Book;
-
-import java.util.List;
-
-public interface BookRepositoryCustom {
-
-    List<Book> findBooksByAuthorNameAndTitle(String authorName, String title);
-    
-}
@@ -1,44 +0,0 @@
-package com.baeldung.persistence.dao;
-
-import com.baeldung.persistence.model.Book;
-import org.springframework.stereotype.Repository;
-
-import javax.persistence.EntityManager;
-import javax.persistence.TypedQuery;
-import javax.persistence.criteria.CriteriaBuilder;
-import javax.persistence.criteria.CriteriaQuery;
-import javax.persistence.criteria.Predicate;
-import javax.persistence.criteria.Root;
-import java.util.ArrayList;
-import java.util.List;
-
-@Repository
-public class BookRepositoryImpl implements BookRepositoryCustom {
-
-    private EntityManager em;
-
-    public BookRepositoryImpl(EntityManager em) {
-        this.em = em;
-    }
-
-    @Override
-    public List<Book> findBooksByAuthorNameAndTitle(String authorName, String title) {
-        CriteriaBuilder cb = em.getCriteriaBuilder();
-        CriteriaQuery<Book> cq = cb.createQuery(Book.class);
-
-        Root<Book> book = cq.from(Book.class);
-        List<Predicate> predicates = new ArrayList<>();
-
-        if (authorName != null) {
-            predicates.add(cb.equal(book.get("author"), authorName));
-        }
-        if (title != null) {
-            predicates.add(cb.like(book.get("title"), "%" + title + "%"));
-        }
-        cq.where(predicates.toArray(new Predicate[0]));
-
-        TypedQuery<Book> query = em.createQuery(cq);
-        return query.getResultList();
-    }
-
-}
@@ -1,25 +0,0 @@
-package com.baeldung.persistence.dao;
-
-import com.baeldung.persistence.model.Book;
-import org.springframework.stereotype.Service;
-
-import java.util.List;
-
-import static com.baeldung.persistence.dao.BookSpecifications.hasAuthor;
-import static com.baeldung.persistence.dao.BookSpecifications.titleContains;
-import static org.springframework.data.jpa.domain.Specification.where;
-
-@Service
-public class BookService {
-
-    private BookRepository bookRepository;
-
-    public BookService(BookRepository bookRepository) {
-        this.bookRepository = bookRepository;
-    }
-
-    public List<Book> query(String author, String title) {
-        return bookRepository.findAll(where(hasAuthor(author)).and(titleContains(title)));
-    }
-
-}
@@ -1,16 +0,0 @@
-package com.baeldung.persistence.dao;
-
-import com.baeldung.persistence.model.Book;
-import org.springframework.data.jpa.domain.Specification;
-
-public class BookSpecifications {
-
-    public static Specification<Book> hasAuthor(String author) {
-        return (book, cq, cb) -> cb.equal(book.get("author"), author);
-    }
-
-    public static Specification<Book> titleContains(String title) {
-        return (book, cq, cb) -> cb.like(book.get("title"), "%" + title + "%");
-    }
-
-}
@@ -0,0 +1,8 @@
+package com.baeldung.persistence.dao;
+
+import com.baeldung.persistence.dao.common.IAuditOperations;
+import com.baeldung.persistence.model.Bar;
+
+public interface IBarAuditableDao extends IBarDao, IAuditOperations<Bar> {
+    //
+}
@@ -0,0 +1,10 @@
+package com.baeldung.persistence.dao;
+
+import java.io.Serializable;
+
+import com.baeldung.persistence.model.Bar;
+import org.springframework.data.repository.CrudRepository;
+
+public interface IBarCrudRepository extends CrudRepository<Bar, Serializable> {
+    //
+}
@@ -0,0 +1,8 @@
+package com.baeldung.persistence.dao;
+
+import com.baeldung.persistence.dao.common.IOperations;
+import com.baeldung.persistence.model.Bar;
+
+public interface IBarDao extends IOperations<Bar> {
+    //
+}
@@ -0,0 +1,8 @@
+package com.baeldung.persistence.dao;
+
+import com.baeldung.persistence.model.Child;
+import com.baeldung.persistence.dao.common.IOperations;
+
+public interface IChildDao extends IOperations<Child> {
+    //
+}
@@ -0,0 +1,8 @@
+package com.baeldung.persistence.dao;
+
+import com.baeldung.persistence.dao.common.IAuditOperations;
+import com.baeldung.persistence.model.Foo;
+
+public interface IFooAuditableDao extends IFooDao, IAuditOperations<Foo> {
+    //
+}
@@ -0,0 +1,8 @@
+package com.baeldung.persistence.dao;
+
+import com.baeldung.persistence.model.Foo;
+import com.baeldung.persistence.dao.common.IOperations;
+
+public interface IFooDao extends IOperations<Foo> {
+    //
+}
@@ -0,0 +1,8 @@
+package com.baeldung.persistence.dao;
+
+import com.baeldung.persistence.model.Parent;
+import com.baeldung.persistence.dao.common.IOperations;
+
+public interface IParentDao extends IOperations<Parent> {
+    //
+}
@@ -0,0 +1,14 @@
+package com.baeldung.persistence.dao.common;
+
+import java.io.Serializable;
+
+import com.google.common.base.Preconditions;
+
+public abstract class AbstractDao<T extends Serializable> implements IOperations<T> {
+
+    protected Class<T> clazz;
+
+    protected final void setClazz(final Class<T> clazzToSet) {
+        clazz = Preconditions.checkNotNull(clazzToSet);
+    }
+}
@@ -0,0 +1,37 @@
+package com.baeldung.persistence.dao.common;
+
+import java.io.Serializable;
+import java.util.List;
+
+import org.hibernate.envers.AuditReader;
+import org.hibernate.envers.AuditReaderFactory;
+import org.hibernate.envers.query.AuditQuery;
+
+@SuppressWarnings("unchecked")
+public class AbstractHibernateAuditableDao<T extends Serializable> extends AbstractHibernateDao<T> implements IAuditOperations<T> {
+
+    @Override
+    public List<T> getEntitiesAtRevision(final Number revision) {
+        final AuditReader auditReader = AuditReaderFactory.get(getCurrentSession());
+        final AuditQuery query = auditReader.createQuery().forEntitiesAtRevision(clazz, revision);
+        final List<T> resultList = query.getResultList();
+        return resultList;
+    }
+
+    @Override
+    public List<T> getEntitiesModifiedAtRevision(final Number revision) {
+        final AuditReader auditReader = AuditReaderFactory.get(getCurrentSession());
+        final AuditQuery query = auditReader.createQuery().forEntitiesModifiedAtRevision(clazz, revision);
+        final List<T> resultList = query.getResultList();
+        return resultList;
+    }
+
+    @Override
+    public List<T> getRevisions() {
+        final AuditReader auditReader = AuditReaderFactory.get(getCurrentSession());
+        final AuditQuery query = auditReader.createQuery().forRevisionsOfEntity(clazz, true, true);
+        final List<T> resultList = query.getResultList();
+        return resultList;
+    }
+
+}
@@ -0,0 +1,59 @@
+package com.baeldung.persistence.dao.common;
+
+import java.io.Serializable;
+import java.util.List;
+
+import org.hibernate.Session;
+import org.hibernate.SessionFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+
+import com.google.common.base.Preconditions;
+
+@SuppressWarnings("unchecked")
+public abstract class AbstractHibernateDao<T extends Serializable> extends AbstractDao<T> implements IOperations<T> {
+
+    @Autowired
+    protected SessionFactory sessionFactory;
+
+    // API
+
+    @Override
+    public T findOne(final long id) {
+        return (T) getCurrentSession().get(clazz, id);
+    }
+
+    @Override
+    public List<T> findAll() {
+        return getCurrentSession().createQuery("from " + clazz.getName()).list();
+    }
+
+    @Override
+    public void create(final T entity) {
+        Preconditions.checkNotNull(entity);
+        getCurrentSession().saveOrUpdate(entity);
+    }
+
+    @Override
+    public T update(final T entity) {
+        Preconditions.checkNotNull(entity);
+        return (T) getCurrentSession().merge(entity);
+    }
+
+    @Override
+    public void delete(final T entity) {
+        Preconditions.checkNotNull(entity);
+        getCurrentSession().delete(entity);
+    }
+
+    @Override
+    public void deleteById(final long entityId) {
+        final T entity = findOne(entityId);
+        Preconditions.checkState(entity != null);
+        delete(entity);
+    }
+
+    protected Session getCurrentSession() {
+        return sessionFactory.getCurrentSession();
+    }
+
+}
@@ -0,0 +1,56 @@
+package com.baeldung.persistence.dao.common;
+
+import java.io.Serializable;
+import java.util.List;
+
+import javax.persistence.EntityManager;
+import javax.persistence.PersistenceContext;
+import javax.persistence.TypedQuery;
+import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.CriteriaQuery;
+import javax.persistence.criteria.Root;
+
+public class AbstractJpaDao<T extends Serializable> extends AbstractDao<T> implements IOperations<T> {
+
+    @PersistenceContext(unitName = "jpaEntityManager")
+    private EntityManager em;
+
+    // API
+
+    @Override
+    public T findOne(final long id) {
+        return em.find(clazz, Long.valueOf(id).intValue());
+    }
+
+    @Override
+    public List<T> findAll() {
+        final CriteriaBuilder cb = em.getCriteriaBuilder();
+        final CriteriaQuery<T> cq = cb.createQuery(clazz);
+        final Root<T> rootEntry = cq.from(clazz);
+        final CriteriaQuery<T> all = cq.select(rootEntry);
+        final TypedQuery<T> allQuery = em.createQuery(all);
+        return allQuery.getResultList();
+    }
+
+    @Override
+    public void create(final T entity) {
+        em.persist(entity);
+    }
+
+    @Override
+    public T update(final T entity) {
+        em.merge(entity);
+        return entity;
+    }
+
+    @Override
+    public void delete(final T entity) {
+        em.remove(entity);
+    }
+
+    @Override
+    public void deleteById(final long entityId) {
+        delete(findOne(entityId));
+    }
+
+}
@@ -0,0 +1,13 @@
+package com.baeldung.persistence.dao.common;
+
+import java.io.Serializable;
+
+import org.springframework.beans.factory.config.BeanDefinition;
+import org.springframework.context.annotation.Scope;
+import org.springframework.stereotype.Repository;
+
+@Repository
+@Scope(BeanDefinition.SCOPE_PROTOTYPE)
+public class GenericHibernateDao<T extends Serializable> extends AbstractHibernateDao<T> implements IGenericDao<T> {
+    //
+}
@@ -0,0 +1,14 @@
+package com.baeldung.persistence.dao.common;
+
+import java.io.Serializable;
+import java.util.List;
+
+public interface IAuditOperations<T extends Serializable> {
+
+    List<T> getEntitiesAtRevision(Number revision);
+
+    List<T> getEntitiesModifiedAtRevision(Number revision);
+
+    List<T> getRevisions();
+
+}
@@ -0,0 +1,7 @@
+package com.baeldung.persistence.dao.common;
+
+import java.io.Serializable;
+
+public interface IGenericDao<T extends Serializable> extends IOperations<T> {
+    //
+}
@@ -0,0 +1,20 @@
+package com.baeldung.persistence.dao.common;
+
+import java.io.Serializable;
+import java.util.List;
+
+public interface IOperations<T extends Serializable> {
+
+    T findOne(final long id);
+
+    List<T> findAll();
+
+    void create(final T entity);
+
+    T update(final T entity);
+
+    void delete(final T entity);
+
+    void deleteById(final long entityId);
+
+}
--- a/Show More
+++ b/Show More