docs: Hibernate sample

samples/java/hibernate/pom.xml

@@ -0,0 +1,56 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>org.example</groupId>
+  <artifactId>hibernate</artifactId>
+  <version>1.0-SNAPSHOT</version>
+
+  <properties>
+    <java.version>1.8</java.version>
+    <maven.compiler.source>1.8</maven.compiler.source>
+    <maven.compiler.target>1.8</maven.compiler.target>
+    <hibernate.version>5.2.13.Final</hibernate.version>
+    <skipTests>false</skipTests>
+    <skipUnits>${skipTests}</skipUnits>
+    <skipITs>true</skipITs>
+    <it.forkCount>8</it.forkCount>
+    <clirr.skip>true</clirr.skip>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+
+    <excludedTests>
+      com.google.cloud.spanner.pgadapter.IntegrationTest,
+      com.google.cloud.spanner.pgadapter.golang.GolangTest,
+      com.google.cloud.spanner.pgadapter.csharp.DotnetTest,
+      com.google.cloud.spanner.pgadapter.python.PythonTest,
+      com.google.cloud.spanner.pgadapter.nodejs.NodeJSTest
+    </excludedTests>
+
+    <spanner.version>6.31.1</spanner.version>
+    <junixsocket.version>2.5.1</junixsocket.version>
+  </properties>
+  <dependencies>
+    <dependency>
+      <groupId>org.hibernate</groupId>
+      <artifactId>hibernate-entitymanager</artifactId>
+      <version>${hibernate.version}</version>
+    </dependency>
+
+    <dependency>
+      <groupId>org.hibernate</groupId>
+      <artifactId>hibernate-core</artifactId>
+      <version>${hibernate.version}</version>
+    </dependency>
+
+    <dependency>
+      <groupId>org.postgresql</groupId>
+      <artifactId>postgresql</artifactId>
+      <version>42.4.2</version>
+    </dependency>
+
+  </dependencies>
+
+</project>

samples/java/hibernate/src/main/java/com/google/cloud/postgres/CustomValueGenerator.java

@@ -0,0 +1,36 @@
+/* 
+ * Hibernate, Relational Persistence for Idiomatic Java
+ * 
+ * JBoss, Home of Professional Open Source
+ * Copyright 2014 Red Hat Inc. and/or its affiliates and other contributors
+ * as indicated by the @authors tag. All rights reserved.
+ * See the copyright.txt in the distribution for a
+ * full listing of individual contributors.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License, v. 2.1.
+ * This program is distributed in the hope that it will be useful, but WITHOUT A
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
+ * You should have received a copy of the GNU Lesser General Public License,
+ * v.2.1 along with this distribution; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA  02110-1301, USA.
+ */
+package com.google.cloud.postgres;
+
+import java.time.LocalDateTime;
+import org.hibernate.Session;
+import org.hibernate.tuple.ValueGenerator;
+
+/**
+ * @author Brett Meyer
+ */
+public class CustomValueGenerator implements ValueGenerator<LocalDateTime> {
+
+	@Override
+	public LocalDateTime generateValue(Session session, Object entity) {
+		return LocalDateTime.now();
+	}
+}

samples/java/hibernate/src/main/java/com/google/cloud/postgres/HibernateSampleTest.java

@@ -0,0 +1,260 @@
+package com.google.cloud.postgres;
+
+import com.google.cloud.postgres.models.Albums;
+import com.google.cloud.postgres.models.Concerts;
+import com.google.cloud.postgres.models.HibernateConfiguration;
+import com.google.cloud.postgres.models.Singers;
+import com.google.cloud.postgres.models.Tracks;
+import com.google.cloud.postgres.models.Venues;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.UUID;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.CriteriaQuery;
+import javax.persistence.criteria.Root;
+import org.hibernate.Session;
+import org.hibernate.query.Query;
+
+public class HibernateSampleTest {
+
+  private static final Logger logger = Logger.getLogger(HibernateSampleTest.class.getName());
+
+  private HibernateConfiguration hibernateConfiguration;
+
+  private List<String> singersId = new ArrayList<>();
+  private List<String> albumsId = new ArrayList<>();
+  private List<Long> tracksId = new ArrayList<>();
+  private List<String> venuesId = new ArrayList<>();
+  private List<String> concertsId = new ArrayList<>();
+
+  public HibernateSampleTest(
+      HibernateConfiguration hibernateConfiguration) {
+    this.hibernateConfiguration = hibernateConfiguration;
+  }
+
+  public void testJPACriteria() {
+    Session s = hibernateConfiguration.openSession();
+    CriteriaBuilder cb = s.getCriteriaBuilder();
+    CriteriaQuery<Singers> singersCriteriaQuery = cb.createQuery(Singers.class);
+    Root<Singers> singersRoot = singersCriteriaQuery.from(Singers.class);
+    singersCriteriaQuery
+        .select(singersRoot)
+        .where(
+            cb.and(cb.equal(singersRoot.get("firstName"), "David"),
+            cb.equal(singersRoot.get("lastName"), "Lee")));
+
+    Query<Singers> singersQuery = s.createQuery(singersCriteriaQuery);
+    List<Singers> singers = singersQuery.getResultList();
+
+    logger.log(Level.INFO, "Listed singer: {0}", singers.size());
+    s.close();
+  }
+
+  public void testHqlUpdate() {
+    Session s = hibernateConfiguration.openSession();
+
+    Singers singers = Utils.createSingers();
+    singers.setLastName("Cord");
+    s.getTransaction().begin();
+    s.saveOrUpdate(singers);
+    s.getTransaction().commit();
+
+    s.getTransaction().begin();
+    Query query = s.createQuery(
+        "update Singers set active=:active "
+            + "where lastName=:lastName and firstName=:firstName");
+    query.setParameter("active", false);
+    query.setParameter("lastName", "Cord");
+    query.setParameter("firstName", "David");
+    query.executeUpdate();
+    s.getTransaction().commit();
+
+    logger.log(Level.INFO, "Updated singer: {0}", s.get(Singers.class, singers.getId()));
+    s.close();
+  }
+
+  public void testHqlList() {
+    Session s = hibernateConfiguration.openSession();
+
+    Query query = s.createQuery("from Singers");
+    List<Singers> list = query.list();
+    logger.log(Level.INFO, "Singers list size: {0}", list.size());
+
+    query = s.createQuery("from Singers order by fullName");
+    query.setFirstResult(2);
+    list = query.list();
+    logger.log(Level.INFO, "Singers list size with first result: {0}", list.size());
+
+    /* Current Limit is not supported. */
+    // query = s.createQuery("from Singers");
+    // query.setMaxResults(2);
+    // list = query.list();
+    // logger.log(Level.INFO, "Singers list size with first result: {0}", list.size());
+
+    query = s.createQuery("select  sum(sampleRate) from Tracks");
+    list = query.list();
+    logger.log(Level.INFO, "Sample rate sum: {0}", list);
+    s.close();
+  }
+
+  public void testOneToManyData() {
+    Session s = hibernateConfiguration.openSession();
+
+    Venues venues = s.get(Venues.class, UUID.fromString(venuesId.get(0)));
+    if (venues == null) {
+      logger.log(Level.SEVERE, "Previously Added Venues Not Found.");
+    }
+    if (venues.getConcerts().size() <= 1) {
+      logger.log(Level.SEVERE, "Previously Added Concerts Not Found.");
+    }
+
+    logger.log(Level.INFO, "Venues fetched: {0}", venues);
+    s.close();
+  }
+
+  public void testDeletingData() {
+    Session s = hibernateConfiguration.openSession();
+
+    Singers singers = Utils.createSingers();
+    s.getTransaction().begin();
+    s.saveOrUpdate(singers);
+    s.getTransaction().commit();
+
+    singers = s.get(Singers.class, singers.getId());
+    if (singers == null) {
+      logger.log(Level.SEVERE, "Added singers not found.");
+    }
+
+    s.getTransaction().begin();
+    s.delete(singers);
+    s.getTransaction().commit();
+
+    singers = s.get(Singers.class, singers.getId());
+    if (singers != null) {
+      logger.log(Level.SEVERE, "Deleted singers found.");
+    }
+    s.close();
+  }
+
+  public void testAddingData() {
+    Session s = hibernateConfiguration.openSession();
+    final Singers singers = Utils.createSingers();
+    final Albums albums = Utils.createAlbums(singers);
+    final Venues venues = Utils.createVenue();
+    final Concerts concerts1 = Utils.createConcerts(singers, venues);
+    final Concerts concerts2 = Utils.createConcerts(singers, venues);
+    final Concerts concerts3 = Utils.createConcerts(singers, venues);
+    s.getTransaction().begin();
+    s.saveOrUpdate(singers);
+    s.saveOrUpdate(albums);
+    s.saveOrUpdate(venues);
+    s.persist(concerts1);
+    s.persist(concerts2);
+    final Tracks tracks1 = Utils.createTracks(albums.getId());
+    s.saveOrUpdate(tracks1);
+    final Tracks tracks2 = Utils.createTracks(albums.getId());
+    s.saveOrUpdate(tracks2);
+    s.persist(concerts3);
+    s.getTransaction().commit();
+    s.clear();
+
+    singersId.add(singers.getId().toString());
+    albumsId.add(albums.getId().toString());
+    venuesId.add(venues.getId().toString());
+    concertsId.add(concerts1.getId().toString());
+    concertsId.add(concerts2.getId().toString());
+    concertsId.add(concerts3.getId().toString());
+    tracksId.add(tracks1.getId().getTrackNumber());
+    tracksId.add(tracks2.getId().getTrackNumber());
+
+    logger.log(Level.INFO, "Created Singer: {0}", singers.getId());
+    logger.log(Level.INFO, "Created Albums: {0}", albums.getId());
+    logger.log(Level.INFO, "Created Venues: {0}", venues.getId());
+    logger.log(Level.INFO, "Created Concerts: {0}", concerts1.getId());
+    logger.log(Level.INFO, "Created Concerts: {0}", concerts2.getId());
+    logger.log(Level.INFO, "Created Concerts: {0}", concerts3.getId());
+    logger.log(Level.INFO, "Created Tracks: {0}", tracks1.getId());
+    logger.log(Level.INFO, "Created Tracks: {0}", tracks2.getId());
+    s.close();
+  }
+
+  public void testSessionRollback() {
+    Session s = hibernateConfiguration.openSession();
+    final Singers singers = Utils.createSingers();
+    s.getTransaction().begin();
+    s.saveOrUpdate(singers);
+    s.getTransaction().rollback();
+    s.clear();
+
+    logger.log(Level.INFO, "Singers that was saved: ", singers.getId());
+    Singers singersFromDb = s.get(Singers.class, singers.getId());
+    if (singersFromDb == null) {
+      logger.log(Level.INFO, "Singers not found as expected.");
+    } else {
+      logger.log(Level.SEVERE, "Singers found. Lookout for the error.");
+    }
+    s.close();
+  }
+
+  public void testForeignKey() {
+    Session s = hibernateConfiguration.openSession();
+
+    final Singers singers = Utils.createSingers();
+    final Albums albums = Utils.createAlbums(singers);
+
+    s.getTransaction().begin();
+    s.saveOrUpdate(singers);
+    s.persist(albums);
+    s.getTransaction().commit();
+    s.clear();
+
+    singersId.add(singers.getId().toString());
+    albumsId.add(albums.getId().toString());
+    logger.log(Level.INFO, "Created Singer: {0}", singers.getId());
+    logger.log(Level.INFO, "Created Albums: {0}", albums.getId());
+    s.close();
+  }
+
+  public void executeTest() {
+    logger.log(Level.INFO, "Testing Foreign Key");
+    testForeignKey();
+    logger.log(Level.INFO, "Foreign Key Test Completed");
+
+    logger.log(Level.INFO, "Testing Session Rollback");
+    testSessionRollback();
+    logger.log(Level.INFO, "Session Rollback Test Completed");
+
+    logger.log(Level.INFO, "Testing Data Insert");
+    testAddingData();
+    logger.log(Level.INFO, "Data Insert Test Completed");
+
+    logger.log(Level.INFO, "Testing Data Delete");
+    testDeletingData();
+    logger.log(Level.INFO, "Data Delete Test Completed");
+
+    logger.log(Level.INFO, "Testing One to Many Fetch");
+    testOneToManyData();
+    logger.log(Level.INFO, "One To Many Fetch Test Completed");
+
+    logger.log(Level.INFO, "Testing HQL List");
+    testHqlList();
+    logger.log(Level.INFO, "HQL List Test Completed");
+
+    logger.log(Level.INFO, "Testing HQL Update");
+    testHqlUpdate();
+    logger.log(Level.INFO, "HQL Update Test Completed");
+
+    logger.log(Level.INFO, "Testing JPA List");
+    testJPACriteria();
+    logger.log(Level.INFO, "JPA List Test Completed");
+  }
+
+  public static void main(String[] args) {
+    HibernateSampleTest hibernateSampleTest =
+        new HibernateSampleTest(HibernateConfiguration.createHibernateConfiguration());
+    hibernateSampleTest.executeTest();
+  }
+
+}