Id | Version | First Name | Last Name | Region | Start Date |
---|---|---|---|---|---|
1 | 90 | Lost | eeeeasdas | West Coast | Jun 4, 2026 |
2 | 18 | Mary | dgzfgdf | East Coast | Jun 10, 2024 |
3 | 20 | 11444iii | km | West Coast | Jan 1, 2024 |
4 | 26 | yuno | 3clover | West Coast | Feb 12, 2008 |
<!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>Grid Data Sources</h3>
By providing your own GridDataSource you can take control of how the data is retrieved,<br/>
In this example we have provided a GridDataSource that is "paged", ie. it retrieves only the Persons needed for the selected page and no more.
<div class="eg">
<t:grid source="persons" rowsPerPage="4" pagerPosition="top"/>
</div>
References:
<a href="http://tapestry.apache.org/5.4/apidocs/org/apache/tapestry5/corelib/components/Grid.html">Grid</a>,
<a href="http://tapestry.apache.org/5.4/apidocs/org/apache/tapestry5/grid/GridDataSource.html">GridDataSource</a>.<br/><br/>
<t:pagelink page="Index">Home</t:pagelink><br/><br/>
The source for @EJB is shown in the @EJB example.<br/><br/>
<t:tabgroup>
<t:sourcecodetab src="/web/src/main/java/jumpstart/web/pages/examples/tables/GridDataSources.tml"/>
<t:sourcecodetab src="/web/src/main/java/jumpstart/web/pages/examples/tables/GridDataSources.java"/>
<t:sourcecodetab src="/web/src/main/resources/META-INF/assets/css/examples/plain.css"/>
<t:sourcecodetab src="/web/src/main/java/jumpstart/web/models/examples/tables/PersonPagedDataSource.java"/>
<t:sourcecodetab src="/business/src/main/java/jumpstart/util/query/SortCriterion.java"/>
<t:sourcecodetab src="/business/src/main/java/jumpstart/util/query/SortDirection.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/Person.java"/>
<t:sourcecodetab src="/business/src/main/java/jumpstart/business/domain/person/Regions.java"/>
</t:tabgroup>
</body>
</html>
package jumpstart.web.pages.examples.tables;
import javax.ejb.EJB;
import jumpstart.business.domain.person.iface.IPersonFinderServiceLocal;
import jumpstart.web.models.examples.tables.PersonPagedDataSource;
import org.apache.tapestry5.annotations.Import;
import org.apache.tapestry5.annotations.InjectComponent;
import org.apache.tapestry5.annotations.Property;
import org.apache.tapestry5.corelib.components.Grid;
import org.apache.tapestry5.grid.GridDataSource;
@Import(stylesheet = "css/examples/plain.css")
public class GridDataSources {
// Screen fields
@Property
private GridDataSource persons;
// Generally useful bits and pieces
@EJB
private IPersonFinderServiceLocal personFinderService;
@InjectComponent
private Grid grid;
// The code
void setupRender() {
persons = new PersonPagedDataSource(personFinderService);
if (grid.getSortModel().getSortConstraints().isEmpty()) {
grid.getSortModel().updateSort("firstName");
}
}
}
.eg {
margin: 20px 0;
padding: 14px;
border: 1px solid #ddd;
border-radius: 6px;
-webkit-border-radius: 6px;
-mox-border-radius: 6px;
}
package jumpstart.web.models.examples.tables;
import java.util.ArrayList;
import java.util.List;
import jumpstart.business.domain.person.Person;
import jumpstart.business.domain.person.iface.IPersonFinderServiceRemote;
import jumpstart.util.query.SortCriterion;
import jumpstart.util.query.SortDirection;
import org.apache.tapestry5.grid.GridDataSource;
import org.apache.tapestry5.grid.SortConstraint;
public class PersonPagedDataSource implements GridDataSource {
private int startIndex;
private List<Person> preparedResults;
private IPersonFinderServiceRemote personFinderService;
public PersonPagedDataSource(IPersonFinderServiceRemote personFinderService) {
this.personFinderService = personFinderService;
}
@Override
public int getAvailableRows() {
long count = personFinderService.countPersons();
return (int) count;
}
@Override
public void prepare(final int startIndex, final int endIndex, final List<SortConstraint> sortConstraints) {
List<SortCriterion> sortCriteria = toSortCriteria(sortConstraints);
// Get a page of persons - ask business service to find them (from the database).
preparedResults = personFinderService.findPersons(startIndex, endIndex - startIndex + 1, sortCriteria);
this.startIndex = startIndex;
}
@Override
public Object getRowValue(final int index) {
return preparedResults.get(index - startIndex);
}
@Override
public Class<Person> getRowType() {
return Person.class;
}
/**
* Converts a list of Tapestry's SortConstraint to a list of our business tier's SortCriterion. The business tier
* does not use SortConstraint because that would create a dependency on Tapestry.
*/
private List<SortCriterion> toSortCriteria(List<SortConstraint> sortConstraints) {
List<SortCriterion> sortCriteria = new ArrayList<SortCriterion>();
for (SortConstraint sortConstraint : sortConstraints) {
String propertyName = sortConstraint.getPropertyModel().getPropertyName();
SortDirection sortDirection = SortDirection.UNSORTED;
switch (sortConstraint.getColumnSort()) {
case ASCENDING:
sortDirection = SortDirection.ASCENDING;
break;
case DESCENDING:
sortDirection = SortDirection.DESCENDING;
break;
default:
}
SortCriterion sortCriterion = new SortCriterion(propertyName, sortDirection);
sortCriteria.add(sortCriterion);
}
return sortCriteria;
}
}
package jumpstart.util.query;
import java.io.Serializable;
@SuppressWarnings("serial")
public class SortCriterion implements Serializable {
private String propertyName;
private SortDirection sortDirection;
public SortCriterion(String propertyName, SortDirection sortDirection) {
this.propertyName = propertyName;
this.sortDirection = sortDirection;
}
public String getPropertyName() {
return propertyName;
}
public SortDirection getSortDirection() {
return sortDirection;
}
}
package jumpstart.util.query;
public enum SortDirection {
ASCENDING, DESCENDING, UNSORTED;
public String toStringForJpql() {
if (this == ASCENDING) {
return "";
}
else if (this == DESCENDING) {
return " desc";
}
else {
return "";
}
}
}
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;
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;
}