activate-2ndlevelcache.xml

<persistence xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.1" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
    <persistence-unit name="my-persistence-unit">
        …

        <!--  enable selective 2nd level cache -->
        <shared-cache-mode>ENABLE_SELECTIVE</shared-cache-mode>

        …

    </persistence-unit>
</persistence>

Author.java

@Entity
public class Author {

	@Id
	@GeneratedValue(strategy = GenerationType.AUTO)
	@Column(name = "id", updatable = false, nullable = false)
	private Long id;

	@Version
	@Column(name = "version")
	private int version;

	@Column
	private String firstName;

	@Column
	private String lastName;

	@ManyToMany(mappedBy="authors")
	private Set<Book> books = new HashSet<Book>();

	// constructors, getters/setters,
	// and everything else is as usual
}

CachedAuthor.java

@Entity
@Cacheable
public class Author {
	…
}

MultipleUpdates.java

public void updateAuthor() {

	EntityManager em = emf.createEntityManager();
	em.getTransaction().begin();

	Author a = em.find(Author.class, 1L);
	a.setFirstName("New first name");

	// execute operations that need to happen
	// during the transaction and between
	// updating first and last name

	a.setLastName("new last name");


	em.getTransaction().commit();
	em.close();
}

ParameterHandling.java

EntityManager em = emf.createEntityManager();
em.getTransaction().begin();

TypedQuery<Author> q = em.createQuery("SELECT a FROM Author a WHERE id = :id", Author.class);
q.setParameter("id", 1L);
Author a = q.getSingleResult();

em.getTransaction().commit();
em.close();

PersistAuthor.java

EntityManager em = emf.createEntityManager();
em.getTransaction().begin();

Author a = new Author();
a.setFirstName("John");
a.setLastName("Doe");
em.persist(a);

em.getTransaction().commit();
em.close();

persistence.xml

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<persistence xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.1" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
    <persistence-unit name="my-persistence-unit">
        <description>My Persistence Unit</description>
        <provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
        <exclude-unlisted-classes>false</exclude-unlisted-classes>
        <properties>
            <property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect" />
            <property name="hibernate.generate_statistics" value="true" />

            <property name="javax.persistence.jdbc.driver" value="org.postgresql.Driver" />
            <property name="javax.persistence.jdbc.url" value="jdbc:postgresql://localhost:5432/test" />
            <property name="javax.persistence.jdbc.user" value="postgres" />
            <property name="javax.persistence.jdbc.password" value="postgres" />
        </properties>
    </persistence-unit>
</persistence>

UpdateAuthor.java

EntityManager em = emf.createEntityManager();
em.getTransaction().begin();

Author a = em.find(Author.class, 1L);
a.setLastName("new last name");

em.getTransaction().commit();
em.close();