JPA Attribute Converters

hibernate5/src/main/java/com/baeldung/hibernate/HibernateUtil.java

@@ -81,6 +81,7 @@ public class HibernateUtil {
         metadataSources.addAnnotatedClass(Bag.class);
         metadataSources.addAnnotatedClass(PointEntity.class);
         metadataSources.addAnnotatedClass(PolygonEntity.class);
+        metadataSources.addAnnotatedClass(com.baeldung.hibernate.pojo.Person.class);
 
         Metadata metadata = metadataSources.buildMetadata();
         return metadata.getSessionFactoryBuilder()

hibernate5/src/main/java/com/baeldung/hibernate/converters/PersonNameConverter.java

@@ -0,0 +1,43 @@
+package com.baeldung.hibernate.converters;
+
+import javax.persistence.AttributeConverter;
+import javax.persistence.Converter;
+
+import com.baeldung.hibernate.pojo.PersonName;
+
+@Converter
+public class PersonNameConverter implements AttributeConverter<PersonName, String> {
+
+    private static final String SEPARATOR = ", ";
+
+    @Override
+    public String convertToDatabaseColumn(PersonName person) {
+        StringBuilder sb = new StringBuilder();
+        if (person.getSurname() != null) {
+            sb.append(person.getSurname());
+            sb.append(SEPARATOR);
+        }
+
+        if (person.getName() != null) {
+            sb.append(person.getName());
+        }
+
+        return sb.toString();
+    }
+
+    @Override
+    public PersonName convertToEntityAttribute(String dbPerson) {
+        String[] pieces = dbPerson.split(SEPARATOR);
+
+        if (pieces == null || pieces.length != 2) {
+            return null;
+        }
+
+        PersonName personName = new PersonName();
+        personName.setSurname(pieces[0]);
+        personName.setName(pieces[1]);
+
+        return personName;
+    }
+
+}

hibernate5/src/main/java/com/baeldung/hibernate/pojo/Person.java

@@ -0,0 +1,32 @@
+package com.baeldung.hibernate.pojo;
+
+import javax.persistence.Convert;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+
+import com.baeldung.hibernate.converters.PersonNameConverter;
+
+@Entity(name = "PersonTable")
+public class Person {
+
+    @Id
+    @GeneratedValue
+    private Long id;
+
+    @Convert(converter = PersonNameConverter.class)
+    private PersonName personName;
+
+    public PersonName getPersonName() {
+        return personName;
+    }
+
+    public void setPersonName(PersonName personName) {
+        this.personName = personName;
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+}

hibernate5/src/main/java/com/baeldung/hibernate/pojo/PersonName.java

@@ -0,0 +1,32 @@
+package com.baeldung.hibernate.pojo;
+
+import java.io.Serializable;
+
+import javax.persistence.Entity;
+
+@Entity
+public class PersonName implements Serializable {
+
+    private static final long serialVersionUID = 7883094644631050150L;
+
+    private String name;
+
+    private String surname;
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getSurname() {
+        return surname;
+    }
+
+    public void setSurname(String surname) {
+        this.surname = surname;
+    }
+
+}

hibernate5/src/test/java/com/baeldung/hibernate/converter/PersonNameConverterTest.java

@@ -0,0 +1,73 @@
+package com.baeldung.hibernate.converter;
+
+import java.io.IOException;
+
+import org.hibernate.Session;
+import org.hibernate.Transaction;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import com.baeldung.hibernate.HibernateUtil;
+import com.baeldung.hibernate.pojo.Person;
+import com.baeldung.hibernate.pojo.PersonName;
+import com.vividsolutions.jts.util.Assert;
+
+public class PersonNameConverterTest {
+
+    private Session session;
+    private Transaction transaction;
+
+    @Before
+    public void setUp() throws IOException {
+        session = HibernateUtil.getSessionFactory()
+            .openSession();
+        transaction = session.beginTransaction();
+
+        session.createNativeQuery("delete from personTable")
+            .executeUpdate();
+
+        transaction.commit();
+        transaction = session.beginTransaction();
+    }
+
+    @After
+    public void tearDown() {
+        transaction.rollback();
+        session.close();
+    }
+
+    @Test
+    public void givenPersonName_WhenSaving_ThenNameAndSurnameConcat() {
+        final String name = "name";
+        final String surname = "surname";
+
+        PersonName personName = new PersonName();
+        personName.setName(name);
+        personName.setSurname(surname);
+
+        Person person = new Person();
+        person.setPersonName(personName);
+
+        Long id = (Long) session.save(person);
+
+        session.flush();
+        session.clear();
+
+        String dbPersonName = (String) session.createNativeQuery("select p.personName from PersonTable p where p.id = :id")
+            .setParameter("id", id)
+            .getSingleResult();
+
+        Assert.equals(surname + ", " + name, dbPersonName);
+
+        Person dbPerson = session.createNativeQuery("select * from PersonTable p where p.id = :id", Person.class)
+            .setParameter("id", id)
+            .getSingleResult();
+
+        Assert.equals(dbPerson.getPersonName()
+            .getName(), name);
+        Assert.equals(dbPerson.getPersonName()
+            .getSurname(), surname);
+    }
+
+}