@EJB
annotation is explained in the next example.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<!-- We need a doctype to allow us to use special characters like
We use a "strict" DTD to make IE follow the alignment rules. -->
<html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_4.xsd">
<body class="container">
<h3>Session Beans</h3>
In JumpStart, the business logic is in Java EE Session Beans, such as PersonFinderService and PersonManagerService.<br/><br/>
Here we've used PersonFinderService to find entity Person with id = 1.
The <code>@EJB</code> annotation is explained in the next example.
<div class="eg">
<t:beandisplay object="person"/>
</div>
For those of you who do not want to use Session Beans, and who do not mind the open-session-in-view pattern, Tapestry has
<a href="http://tapestry.apache.org/integrating-with-jpa.html">JPA Integration</a> and
<a href="http://tapestry.apache.org/hibernate.html">Hibernate Integration</a>.<br/><br/>
References: <a href="https:/tapestry-jumpstart.org/faq.html">"Why EJB3?" in JumpStart FAQ</a>,
<a href="http://docs.oracle.com/javaee/7/tutorial/doc/ejb-intro001.htm#GIPMB">What is an Enterprise Bean?</a>.<br/><br/>
<t:pagelink page="Index">Home</t:pagelink><br/><br/>
<t:tabgroup>
<t:sourcecodetab src="/web/src/main/java/jumpstart/web/pages/examples/state/SessionBeans.tml"/>
<t:sourcecodetab src="/web/src/main/java/jumpstart/web/pages/examples/state/SessionBeans.java"/>
<t:sourcecodetab src="/web/src/main/resources/META-INF/assets/css/examples/plain.css"/>
<t:sourcecodetab src="/business/src/main/java/jumpstart/business/domain/person/iface/IPersonFinderServiceLocal.java"/>
<t:sourcecodetab src="/business/src/main/java/jumpstart/business/domain/person/iface/IPersonFinderServiceRemote.java"/>
<t:sourcecodetab src="/business/src/main/java/jumpstart/business/domain/person/PersonFinderService.java"/>
<t:sourcecodetab src="/business/src/main/java/jumpstart/business/domain/person/iface/IPersonManagerServiceLocal.java"/>
<t:sourcecodetab src="/business/src/main/java/jumpstart/business/domain/person/iface/IPersonManagerServiceRemote.java"/>
<t:sourcecodetab src="/business/src/main/java/jumpstart/business/domain/person/PersonManagerService.java"/>
<t:sourcecodetab src="/business/src/main/java/jumpstart/business/domain/person/Person.java"/>
<t:sourcecodetab src="/business/src/main/java/jumpstart/business/domain/person/Regions.java"/>
<t:sourcecodetab src="/business/src/main/java/jumpstart/business/domain/person/ValidationException.java"/>
</t:tabgroup>
</body>
</html>
package jumpstart.web.pages.examples.state;
import javax.ejb.EJB;
import jumpstart.business.domain.person.Person;
import jumpstart.business.domain.person.iface.IPersonFinderServiceLocal;
import org.apache.tapestry5.annotations.Import;
import org.apache.tapestry5.annotations.Property;
@Import(stylesheet = "css/examples/plain.css")
public class SessionBeans {
// Screen fields
@Property
private Person person;
// Generally useful bits and pieces
@EJB
private IPersonFinderServiceLocal personFinderService;
// The code
void setupRender() throws Exception {
person = personFinderService.findPerson(1L);
if (person == null) {
throw new IllegalStateException("Database data has not been set up!");
}
}
}
.eg {
margin: 20px 0;
padding: 14px;
border: 1px solid #ddd;
border-radius: 6px;
-webkit-border-radius: 6px;
-mox-border-radius: 6px;
}
package jumpstart.business.domain.person.iface;
/**
* The <code>IPersonServiceLocal</code> bean exposes the business methods in the interface.
*/
public interface IPersonFinderServiceLocal extends IPersonFinderServiceRemote {
}
package jumpstart.business.domain.person.iface;
import java.util.List;
import jumpstart.business.domain.person.Person;
import jumpstart.business.domain.person.Regions;
import jumpstart.util.query.SortCriterion;
/**
* The <code>IPersonFinderServiceRemote</code> bean exposes the business methods in the interface.
*/
public interface IPersonFinderServiceRemote {
// Person
Person findPerson(Long id);
long countPersons();
List<Person> findPersons(int maxResults);
List<Person> findPersons(String partialName, int maxResults);
List<Person> findPersonsByFirstName(String firstName);
List<Person> findPersonsByLastName(String lastName);
long countPersons(String partialName);
List<Person> findPersons(String partialName, int startIndex, int maxResults);
List<Person> findPersons(int startIndex, int maxResults, List<SortCriterion> sortCriteria);
long countPersons(String firstNameStartsWith, String lastNameStartsWith, Regions region);
List<Person> findPersons(String firstNameStartsWith, String lastNameStartsWith, Regions region, int startIndex,
int maxResults, List<SortCriterion> sortCriteria);
}
package jumpstart.business.domain.person;
import java.util.Arrays;
import java.util.List;
import javax.ejb.Local;
import javax.ejb.Remote;
import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.Query;
import jumpstart.business.domain.person.iface.IPersonFinderServiceLocal;
import jumpstart.business.domain.person.iface.IPersonFinderServiceRemote;
import jumpstart.util.query.SortCriterion;
@Stateless
@Local(IPersonFinderServiceLocal.class)
@Remote(IPersonFinderServiceRemote.class)
public class PersonFinderService implements IPersonFinderServiceLocal, IPersonFinderServiceRemote {
@PersistenceContext(unitName = "jumpstart")
private EntityManager em;
public Person findPerson(Long id) {
return em.find(Person.class, id);
}
public long countPersons() {
return (Long) em.createQuery("select count(p) from Person p").getSingleResult();
}
@SuppressWarnings("unchecked")
public List<Person> findPersons(int maxResults) {
return em.createQuery("select p from Person p order by lower(p.firstName), lower(p.lastName)")
.setMaxResults(maxResults).getResultList();
}
@SuppressWarnings("unchecked")
public List<Person> findPersons(String partialName, int maxResults) {
String searchName = partialName == null ? "" : partialName.toLowerCase();
StringBuilder buf = new StringBuilder();
buf.append("select p from Person p");
buf.append(" where lower(firstName) like :firstName");
buf.append(" or lower(lastName) like :lastName");
buf.append(" order by lower(p.firstName), lower(p.lastName)");
Query q = em.createQuery(buf.toString());
q.setParameter("firstName", "%" + searchName + "%");
q.setParameter("lastName", "%" + searchName + "%");
List<Person> l = q.setMaxResults(maxResults).getResultList();
return l;
}
@SuppressWarnings("unchecked")
public List<Person> findPersonsByFirstName(String firstName) {
String searchName = firstName == null ? "" : firstName.trim().toLowerCase();
StringBuilder buf = new StringBuilder();
buf.append("select p from Person p");
buf.append(" where lower(p.firstName) = :searchName");
buf.append(" order by lower(p.firstName), lower(p.lastName)");
Query q = em.createQuery(buf.toString());
q.setParameter("searchName", searchName);
List<Person> l = q.getResultList();
return l;
}
@SuppressWarnings("unchecked")
public List<Person> findPersonsByLastName(String lastName) {
String searchName = lastName == null ? "" : lastName.trim().toLowerCase();
StringBuilder buf = new StringBuilder();
buf.append("select p from Person p");
buf.append(" where lower(p.lastName) = :searchName");
buf.append(" order by lower(p.lastName), lower(p.firstName)");
Query q = em.createQuery(buf.toString());
q.setParameter("searchName", searchName);
List<Person> l = q.getResultList();
return l;
}
public long countPersons(String partialName) {
return (Long) findPersons(true, partialName, 0, 0);
}
@SuppressWarnings("unchecked")
public List<Person> findPersons(String partialName, int startIndex, int maxResults) {
return (List<Person>) findPersons(false, partialName, startIndex, maxResults);
}
@SuppressWarnings("unchecked")
private Object findPersons(boolean counting, String partialName, int startIndex, int maxResults) {
String searchName = partialName == null ? "" : partialName.toLowerCase();
StringBuilder buf = new StringBuilder();
if (counting) {
buf.append("select count(p) from Person p");
}
else {
buf.append("select p from Person p");
}
buf.append(" where lower(firstName) like :firstName");
buf.append(" or lower(lastName) like :lastName");
if (!counting) {
buf.append(" order by lower(p.firstName), lower(p.lastName)");
}
Query q = em.createQuery(buf.toString());
q.setParameter("firstName", "%" + searchName + "%");
q.setParameter("lastName", "%" + searchName + "%");
if (counting) {
Long qty = (Long) q.getSingleResult();
return qty;
}
else {
List<Person> l = q.setFirstResult(startIndex).setMaxResults(maxResults).getResultList();
return l;
}
}
@SuppressWarnings("unchecked")
public List<Person> findPersons(int startIndex, int maxResults, List<SortCriterion> sortCriteria) {
final List<String> PROPERTIES_TO_LOWER_FOR_SORT = Arrays.asList("firstName", "lastName");
// Here we use JPQL. An alternative is to use javax.persistence.criteria.CriteriaQuery. For an example see
// Tapestry's JpaGridDataSource.
StringBuilder buf = new StringBuilder();
buf.append("select p from Person p");
buf.append(" order by ");
boolean firstOrderByItem = true;
boolean orderByIncludesId = false;
for (SortCriterion sortCriterion : sortCriteria) {
String propertyName = sortCriterion.getPropertyName();
// Append an "order by" item, eg. "startDate", or ", lower(firstName) desc".
if (!firstOrderByItem) {
buf.append(", ");
}
if (PROPERTIES_TO_LOWER_FOR_SORT.contains(propertyName)) {
buf.append("lower(").append(propertyName).append(")");
}
else {
buf.append(propertyName);
}
buf.append(sortCriterion.getSortDirection().toStringForJpql());
// We need to know later whether the "order by" includes id.
if (propertyName.equals("id")) {
orderByIncludesId = true;
}
firstOrderByItem = false;
}
// Ensure sequence is predictable by ensuring a unique property, id, is in the "order by".
if (!orderByIncludesId) {
if (!firstOrderByItem) {
buf.append(", ");
}
buf.append("id");
}
Query q = em.createQuery(buf.toString());
List<Person> l = q.setFirstResult(startIndex).setMaxResults(maxResults).getResultList();
return l;
}
public long countPersons(String firstNameStartsWith, String lastNameStartsWith, Regions region) {
return (Long) findPersons(true, firstNameStartsWith, lastNameStartsWith, region, 0, 0, null);
}
@SuppressWarnings("unchecked")
public List<Person> findPersons(String firstNameStartsWith, String lastNameStartsWith, Regions region,
int startIndex, int maxResults, List<SortCriterion> sortCriteria) {
return (List<Person>) findPersons(false, firstNameStartsWith, lastNameStartsWith, region, startIndex,
maxResults, sortCriteria);
}
/**
* Finds persons who match the criteria.
* If counting == true, returns the count of persons found, as a Long.
* Else, returns the persons found, as a List<Person>.
*/
@SuppressWarnings("unchecked")
private Object findPersons(boolean counting, String firstNameStartsWith, String lastNameStartsWith, Regions region,
int startIndex, int maxResults, List<SortCriterion> sortCriteria) {
final List<String> PROPERTIES_TO_LOWER_FOR_SORT = Arrays.asList("firstName", "lastName");
String searchFirstName = firstNameStartsWith == null ? "" : firstNameStartsWith.toLowerCase();
String searchLastName = lastNameStartsWith == null ? "" : lastNameStartsWith.toLowerCase();
StringBuilder buf = new StringBuilder();
if (counting) {
buf.append("select count(p) from Person p");
}
else {
buf.append("select p from Person p");
}
buf.append(" where lower(firstName) like :firstName");
buf.append(" and lower(lastName) like :lastName");
if (region != null) {
buf.append(" and region = :region");
}
if (!counting) {
buf.append(" order by ");
boolean firstOrderByItem = true;
boolean orderByIncludesId = false;
for (SortCriterion sortCriterion : sortCriteria) {
String propertyName = sortCriterion.getPropertyName();
// Append an "order by" item, eg. "startDate", or ", lower(firstName) desc".
if (!firstOrderByItem) {
buf.append(", ");
}
if (PROPERTIES_TO_LOWER_FOR_SORT.contains(propertyName)) {
buf.append("lower(").append(propertyName).append(")");
}
else {
buf.append(propertyName);
}
buf.append(sortCriterion.getSortDirection().toStringForJpql());
// We need to know later whether the "order by" includes id.
if (propertyName.equals("id")) {
orderByIncludesId = true;
}
firstOrderByItem = false;
}
// Ensure sequence is predictable by ensuring a unique property, id, is in the "order by".
if (!orderByIncludesId) {
if (!firstOrderByItem) {
buf.append(", ");
}
buf.append("id");
}
}
Query q = em.createQuery(buf.toString());
q.setParameter("firstName", searchFirstName + "%");
q.setParameter("lastName", searchLastName + "%");
if (region != null) {
q.setParameter("region", region);
}
if (counting) {
Long qty = (Long) q.getSingleResult();
return qty;
}
else {
List<Person> l = q.setFirstResult(startIndex).setMaxResults(maxResults).getResultList();
return l;
}
}
}
package jumpstart.business.domain.person.iface;
/**
* The <code>IPersonManagerServiceLocal</code> bean exposes the business methods in the interface.
*/
public interface IPersonManagerServiceLocal extends IPersonManagerServiceRemote {
}
package jumpstart.business.domain.person.iface;
import java.util.List;
import jumpstart.business.commons.IdVersion;
import jumpstart.business.domain.person.Person;
/**
* The <code>IPersonManagerServiceRemote</code> bean exposes the business methods in the interface.
*/
public interface IPersonManagerServiceRemote {
// Person
Person createPerson(Person person);
void createPersons(List<Person> persons);
Person changePerson(Person person);
void changePersons(List<Person> persons);
void changePersonsByDTOs(List<PersonDTO> persons);
void bulkEditPersons(List<Person> personsToCreate, List<Person> personsToChange, List<IdVersion> personsToDelete);
void bulkEditPersonsByDTOs(List<PersonDTO> personsToCreate, List<PersonDTO> personsToChange,
List<IdVersion> personsToDelete);
void deletePerson(Long id, Integer version);
}
package jumpstart.business.domain.person;
import java.util.List;
import javax.ejb.Local;
import javax.ejb.Remote;
import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.EntityNotFoundException;
import javax.persistence.OptimisticLockException;
import javax.persistence.PersistenceContext;
import jumpstart.business.commons.IdVersion;
import jumpstart.business.domain.person.iface.IPersonManagerServiceLocal;
import jumpstart.business.domain.person.iface.IPersonManagerServiceRemote;
import jumpstart.business.domain.person.iface.PersonDTO;
@Stateless
@Local(IPersonManagerServiceLocal.class)
@Remote(IPersonManagerServiceRemote.class)
public class PersonManagerService implements IPersonManagerServiceLocal, IPersonManagerServiceRemote {
@PersistenceContext(unitName = "jumpstart")
public EntityManager em;
public Person createPerson(Person person) {
em.persist(person);
return person;
}
public void createPersons(List<Person> persons) {
for (Person person : persons) {
em.persist(person);
}
}
public Person changePerson(Person person) {
Person p = em.merge(person);
// Flush to work around OPENEJB issue https://issues.apache.org/jira/browse/OPENEJB-782
em.flush();
// If id is different it means the person did not exist so merge has created a new one.
if (!p.getId().equals(person.getId())) {
throw new EntityNotFoundException("Person no longer exists.");
}
return p;
}
public void changePersons(List<Person> persons) {
for (Person person : persons) {
Person p = em.merge(person);
// If id is different it means the person did not exist so merge has created a new one.
if (!p.getId().equals(person.getId())) {
throw new EntityNotFoundException("Person no longer exists.");
}
}
}
public void changePersonsByDTOs(List<PersonDTO> persons) {
for (PersonDTO person : persons) {
Person p = em.find(Person.class, person.getId());
if (p == null) {
throw new EntityNotFoundException("Person no longer exists.");
}
if (!p.getVersion().equals(person.getVersion())) {
throw new OptimisticLockException();
}
p.setFirstName(person.getFirstName());
}
}
public void bulkEditPersons(List<Person> personsToCreate, List<Person> personsToChange,
List<IdVersion> personsToDelete) {
for (Person person : personsToCreate) {
em.persist(person);
}
for (Person person : personsToChange) {
Person p = em.merge(person);
// If id is different it means the person did not exist so merge has created a new one.
if (!p.getId().equals(person.getId())) {
throw new EntityNotFoundException("Person no longer exists.");
}
}
for (IdVersion idVersion : personsToDelete) {
Person p = em.find(Person.class, idVersion.getId());
if (p == null) {
throw new EntityNotFoundException("Person no longer exists.");
}
if (!p.getVersion().equals(idVersion.getVersion())) {
throw new OptimisticLockException();
}
em.remove(p);
}
}
public void bulkEditPersonsByDTOs(List<PersonDTO> personsToCreate, List<PersonDTO> personsToChange,
List<IdVersion> personsToDelete) {
for (PersonDTO p : personsToCreate) {
Person person = new Person(p.getFirstName(), p.getLastName(), p.getRegion(), p.getStartDate());
em.persist(person);
}
for (PersonDTO person : personsToChange) {
Person p = em.find(Person.class, person.getId());
if (p == null) {
throw new EntityNotFoundException("Person no longer exists.");
}
if (!p.getVersion().equals(person.getVersion())) {
throw new OptimisticLockException();
}
p.setFirstName(person.getFirstName());
p.setLastName(person.getLastName());
p.setRegion(person.getRegion());
p.setStartDate(person.getStartDate());
}
for (IdVersion idVersion : personsToDelete) {
Person p = em.find(Person.class, idVersion.getId());
if (p == null) {
throw new EntityNotFoundException("Person no longer exists.");
}
if (!p.getVersion().equals(idVersion.getVersion())) {
throw new OptimisticLockException();
}
em.remove(p);
}
}
public void deletePerson(Long id, Integer version) {
Person p = em.find(Person.class, id);
if (p == null) {
throw new EntityNotFoundException("Person no longer exists.");
}
if (!p.getVersion().equals(version)) {
throw new OptimisticLockException();
}
em.remove(p);
// Flush to work around OPENEJB issue https://issues.apache.org/jira/browse/OPENEJB-782
em.flush();
}
}
package jumpstart.business.domain.person;
import java.io.Serializable;
import java.util.Date;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.EnumType;
import javax.persistence.Enumerated;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.PrePersist;
import javax.persistence.PreUpdate;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;
import javax.persistence.Version;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;
/**
* The Person entity.
*/
@Entity
@SuppressWarnings("serial")
public class Person implements Serializable {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(nullable = false)
private Long id;
@Version
@Column(nullable = false)
private Integer version;
@Column(length = 10, nullable = false)
@NotNull
@Size(max = 10)
private String firstName;
@Column(length = 10, nullable = false)
@NotNull
@Size(max = 10)
private String lastName;
@Enumerated(EnumType.STRING)
@NotNull
private Regions region;
@Temporal(TemporalType.DATE)
@NotNull
private Date startDate;
public String toString() {
final String DIVIDER = ", ";
StringBuilder buf = new StringBuilder();
buf.append(this.getClass().getSimpleName() + ": ");
buf.append("[");
buf.append("id=" + id + DIVIDER);
buf.append("version=" + version + DIVIDER);
buf.append("firstName=" + firstName + DIVIDER);
buf.append("lastName=" + lastName + DIVIDER);
buf.append("region=" + region + DIVIDER);
buf.append("startDate=" + startDate);
buf.append("]");
return buf.toString();
}
// Default constructor is required by JPA.
public Person() {
}
public Person(String firstName, String lastName, Regions region, Date startDate) {
super();
this.firstName = firstName;
this.lastName = lastName;
this.region = region;
this.startDate = startDate;
}
// The need for an equals() method is discussed at http://www.hibernate.org/109.html
@Override
public boolean equals(Object obj) {
return (obj == this) || (obj instanceof Person) && id != null && id.equals(((Person) obj).getId());
}
// The need for a hashCode() method is discussed at http://www.hibernate.org/109.html
@Override
public int hashCode() {
return id == null ? super.hashCode() : id.hashCode();
}
@PrePersist
@PreUpdate
public void validate() throws ValidationException {
}
public Long getId() {
return id;
}
public Integer getVersion() {
return version;
}
public void setVersion(Integer version) {
this.version = version;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public Regions getRegion() {
return region;
}
public void setRegion(Regions region) {
this.region = region;
}
public Date getStartDate() {
return startDate;
}
public void setStartDate(Date startDate) {
this.startDate = startDate;
}
}
package jumpstart.business.domain.person;
public enum Regions {
EAST_COAST, WEST_COAST;
}
package jumpstart.business.domain.person;
import javax.ejb.ApplicationException;
@ApplicationException(rollback = true)
@SuppressWarnings("serial")
public class ValidationException extends Exception {
public ValidationException(String message) {
super(message);
}
}