我对DataTable - Lazy Loading有疑问。我认为问题出在IdiomasBean.java(TableBean.java 的等效项)中,如果我输入:
public IdiomasBean() { }
public LazyDataModel<Idiomas> getLazyModel() {
lazyModel = new LazyIdiomasDataModel(idiomasBo.findAllIdiomas());
return lazyModel;
}
我得到了正确的数据表,但是...... sortBy
,filterBy
并且onRowSelect
不工作。
public IdiomasBean() {
lazyModel = new LazyIdiomasDataModel(idiomasList);
}
public LazyDataModel<Idiomas> getLazyModel() {
return lazyModel;
}
我得到:java.lang.NullPointerException 这是堆栈跟踪:
> at
> brany.view.lazyDataModel.LazyIdiomasDataModel.load(LazyIdiomasDataModel.java:42)
> at
> org.primefaces.component.datatable.DataTable.loadLazyData(DataTable.java:690)
> at
> org.primefaces.component.datatable.DataTableRenderer.encodeMarkup(DataTableRenderer.java:192)
> at
> org.primefaces.component.datatable.DataTableRenderer.encodeEnd(DataTableRenderer.java:108)
> at
> javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:875)
> at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1763)
> at javax.faces.render.Renderer.encodeChildren(Renderer.java:168) at
> javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845)
> at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1756)
> at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759)
> at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759)
> at
> com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:401)
> at
> com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:131)
> at
> com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:121)
> at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) at
> com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
> at javax.faces.webapp.FacesServlet.service(FacesServlet.java:410) at
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
> at
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
> at
> org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:393)
> at
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
> at
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
> at
> org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:225)
> at
> org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
> at
> org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
> at
> org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
> at
> org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
> at
> org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
> at
> org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
> at
> org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
> at
> org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:999)
> at
> org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:565)
> at
> org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:307)
> at
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
> at
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
> at java.lang.Thread.run(Thread.java:722)
这是其余的代码:
索引.xhtml
<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:p="http://primefaces.org/ui">
<h:head>
<title>PRUEBA PRIMEFACES</title>
</h:head>
<h:body>
<h:form id="form">
<p:dataTable var="id" value="#{idiomasBean.lazyModel}" paginator="true" rows="10"
paginatorTemplate="{RowsPerPageDropdown} {FirstPageLink} {PreviousPageLink} {CurrentPageReport} {NextPageLink} {LastPageLink}"
rowsPerPageTemplate="5,10,15" selectionMode="single" selection="#{idiomasBean.selectedIdiomas}" id="idiomasTable" lazy="true">
<p:ajax event="rowSelect" listener="#{idiomasBean.onRowSelect}" update=":form:display" oncomplete="idiomasDialog.show()" />
<p:column headerText="Nombre" sortBy="#{id.nombre}" filterBy="#{id.nombre}">
<h:outputText value="#{id.nombre}" />
</p:column>
<p:column headerText="Año" sortBy="#{id.name}" filterBy="#{id.name}">
<h:outputText value="#{id.name}" />
</p:column>
</p:dataTable>
<p:dialog header="Detalles Idioma" widgetVar="idiomasDialog" resizable="false"
showEffect="explode" hideEffect="explode">
<h:panelGrid id="display" columns="2" cellpadding="4">
<h:outputText value="Nombre:" />
<h:outputText value="#{idiomasBean.selectedIdiomas.nombre}" style="font-weight:bold"/>
<h:outputText value="Valoración:" />
<h:outputText value="#{idiomasBean.selectedIdiomas.valoracion}" style="font-weight:bold"/>
</h:panelGrid>
</p:dialog>
</h:form>
</h:body>
</html>
idiomasBean.java
package brany.spring.managedBean;
import brany.model.bo.imp.IdiomasBo;
import brany.model.entityBean.Idiomas;
import brany.view.lazyDataModel.LazyIdiomasDataModel;
import java.util.List;
import org.primefaces.model.LazyDataModel;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Controller;
@Controller
@Scope("session")
public class IdiomasBean implements java.io.Serializable {
private String nombre;
private String name;
@Autowired
private IdiomasBo idiomasBo;
private List<Idiomas> idiomasList;
private LazyDataModel<Idiomas> lazyModel;
private Idiomas selectedIdiomas;
public IdiomasBean() {
lazyModel = new LazyIdiomasDataModel(idiomasList);
}
public void setIdiomasBo (IdiomasBo idiomasBo) {
this.idiomasBo = idiomasBo;
}
public List<Idiomas> getIdiomasList() {
idiomasList = idiomasBo.findAllIdiomas();
return idiomasList;
}
public IdiomasBo getIdiomasBo () {
return idiomasBo;
}
public String getNombre() {
return this.nombre;
}
public void setNombre(String nombre) {
this.nombre = nombre;
}
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
public LazyDataModel<Idiomas> getLazyModel() {
return lazyModel;
}
public Idiomas getSelectedIdiomas() {
return selectedIdiomas;
}
public void setSelectedIdiomas(Idiomas selectedIdiomas) {
this.selectedIdiomas = selectedIdiomas;
}
}
LazyIdiomasDataModel.java
package brany.view.lazyDataModel;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import brany.model.entityBean.Idiomas;
import brany.view.util.LazySorter;
import org.primefaces.model.LazyDataModel;
import org.primefaces.model.SortOrder;
public class LazyIdiomasDataModel extends LazyDataModel<Idiomas> {
private List<Idiomas> datasource;
public LazyIdiomasDataModel(List<Idiomas> datasource) {
this.datasource = datasource;
}
@Override
public Idiomas getRowData(String rowKey) {
for(Idiomas idiomas : datasource) {
if(idiomas.getNombre().equals(rowKey))
return idiomas;
}
return null;
}
@Override
public Object getRowKey(Idiomas idiomas) {
return idiomas.getNombre();
}
@Override
public List<Idiomas> load(int first, int pageSize, String sortField, SortOrder sortOrder, Map<String,String> filters) {
List<Idiomas> data = new ArrayList<Idiomas>();
//filter
for(Idiomas idiomas : datasource) {
boolean match = true;
for(Iterator<String> it = filters.keySet().iterator(); it.hasNext();) {
try {
String filterProperty = it.next();
String filterValue = filters.get(filterProperty);
String fieldValue = String.valueOf(idiomas.getClass().getField(filterProperty).get(idiomas));
if(filterValue == null || fieldValue.startsWith(filterValue)) {
match = true;
}
else {
match = false;
break;
}
} catch(Exception e) {
match = false;
}
}
if(match) {
data.add(idiomas);
}
}
//sort
if(sortField != null) {
Collections.sort(data, new LazySorter(sortField, sortOrder));
}
//rowCount
int dataSize = data.size();
this.setRowCount(dataSize);
//paginate
if(dataSize > pageSize) {
try {
return data.subList(first, first + pageSize);
}
catch(IndexOutOfBoundsException e) {
return data.subList(first, first + (dataSize % pageSize));
}
}
else {
return data;
}
}
}
IdiomasBo.java
package brany.model.bo.imp;
import brany.model.bo.IIdiomasBo;
import brany.model.dao.imp.IdiomasDao;
import brany.model.entityBean.Idiomas;
import java.util.List;
import org.springframework.stereotype.Service;
@Service
public class IdiomasBo implements IIdiomasBo {
private IdiomasDao idiomasDao;
public void setIdiomasDao (IdiomasDao idiomasDao) {
this.idiomasDao = idiomasDao;
}
@Override
public List<Idiomas> findAllIdiomas() {
return this.idiomasDao.findAllIdiomas();
}
}
IdiomasDao.java
package brany.model.dao.imp;
import brany.model.dao.IIdiomasDao;
import brany.model.entityBean.Idiomas;
import java.util.List;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;
import org.springframework.stereotype.Repository;
@Repository
public class IdiomasDao extends HibernateDaoSupport implements IIdiomasDao {
@Override
public List<Idiomas> findAllIdiomas() {
return getHibernateTemplate().find("from Idiomas");
}
}
成语.java
package brany.model.entityBean;
public class Idiomas implements java.io.Serializable {
private Integer ididioma;
private String nombre;
private String name;
public Idiomas() {
}
public Idiomas(String nombre, String name) {
this.nombre = nombre;
this.name = name;
}
public Integer getIdidioma() {
return this.ididioma;
}
public void setIdidioma(Integer ididioma) {
this.ididioma = ididioma;
}
public String getNombre() {
return this.nombre;
}
public void setNombre(String nombre) {
this.nombre = nombre;
}
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
}
LazySorter.java
package brany.view.util;
import java.util.Comparator;
import brany.spring.util.ReflectionUtil;
import org.primefaces.model.SortOrder;
public class LazySorter<T> implements Comparator<T> {
private String sortField;
private SortOrder sortOrder;
public LazySorter(String sortField, SortOrder sortOrder) {
this.sortField = sortField;
this.sortOrder = sortOrder;
}
@Override
public int compare(Object first, Object second) {
try {
Object value1 = ReflectionUtil.getValue(first, sortField);
Object value2 = ReflectionUtil.getValue(second, sortField);
int value = 0;
if(value1 instanceof Comparable)
value = ((Comparable) value1).compareTo(value2);
else if(value1 instanceof Boolean && !value1.equals(value2))
value = (Boolean)value1 ? 1 : -1;
return SortOrder.ASCENDING.equals(sortOrder) ? value : -1 * value;
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
ReflectionUtil.java
package brany.spring.util;
public class ReflectionUtil {
public static Object getValue(Object object, String fieldName) {
try {
String getterName = "get" + Character.toUpperCase(fieldName.charAt(0)) + fieldName.substring(1);
return object.getClass().getMethod(getterName).invoke(object);
} catch (Exception e) {
return null;
}
}
}
面孔-config.xml
<?xml version="1.0" encoding="UTF-8"?>
<faces-config version="2.1"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-facesconfig_2_1.xsd">
<application>
<!-- Estamos activando el soporte de Spring para la inyección de dependencias
de tal forma que JSF sabrá que si no encuentra un bean bajo su contexto debe
ir a buscarlo al contexto de Spring -->
<el-resolver>
org.springframework.web.jsf.el.SpringBeanFacesELResolver
</el-resolver>
</application>
<!-- Definimos el bean que va a trabajar con la aplicación que tiene asociada la
clase IdiomasBean y seteamos el atributo (property) idiomasBo-->
<managed-bean>
<managed-bean-name>idiomasBean</managed-bean-name>
<managed-bean-class>brany.spring.managedBean.IdiomasBean</managed-bean-class>
<managed-bean-scope>session</managed-bean-scope>
<managed-property>
<property-name>idiomasBo</property-name>
<value>#{idiomasBo}</value>
</managed-property>
</managed-bean>
</faces-config>
有没有人有任何解决方案?
谢谢!