我如何验证primefaces树<p：tree>
看起来primefaces <p:tree>不是一个EditableValueHolder，尽管它提供了使树可选的功能。 对我来说，这看起来像EditableValueHolder定义，因为它既包含值（所选节点的列表），也是可编辑的（可以更改选择）。 在使树可选时，它基本上将它变成selectOneXxx / selectManyXxx。 这是我使用这个小部件的时尚。 但是，不是EditableValueHolder，我不能直接附加验证器。 我可以使用actionListener将验证添加到表单提交操作中，但是它超出了适当的生命周期阶段，并且更难以获取UITree组件来检查属性，例如验证失败的i18n消息。 有没有人处理过这个？ 你是做什么？
----------编辑----------
我发现一个问题发布在primefaces错误跟踪器中，似乎相关：
http://code.google.com/p/primefaces/issues/detail?id=4137
和一个论坛帖子：
http://forum.primefaces.org/viewtopic.php?f=3&t=22340
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这是我想出的解决方案。 一些jQuery非常有趣，因为它使用服务器端el来生成客户端JavaScript。 但大多数情况下它是有效的。 只需要弄清楚为什么一个空数组跳过验证......但多数民众赞成在另一个故事。
<h:panelGroup id="pnpCois" styleClass="pnp-input-group pnp-cois">
<h:outputLabel for="inputCois"
value="#{i18n['communities-of-interest']}" />
<p:tree id="inputCois"
value="#{subscriptions.selected.coiTreeRootNode}" var="node"
selectionMode="checkbox"
selection="#{subscriptions.selected.selectedCoiNodes}">
<p:ajax event="select" process="@this :#{component.clientId}_validator" update="@this"
onstart="$('##{component.clientId}_validator'.replace(':',':')).val($('##{component.clientId}_selection'.replace(':',':')).val());" />
<p:ajax event="unselect" process="@this :#{component.clientId}_validator" update="@this"
onstart="$('##{component.clientId}_validator'.replace(':',':')).val($('##{component.clientId}_selection'.replace(':',':')).val());" />
<p:treeNode>
<h:outputText value="#{node}" />
</p:treeNode>
</p:tree>
<h:inputHidden id="inputCois_validator">
<f:converter converterId="asias.stringCsvToArray" />
<f:validator validatorId="asias.atLeastOneSelected" />
<f:attribute name="atLeastOneSelectedMessage"
value="#{i18n['at-least-one-coi-must-be-selected']}" />
</h:inputHidden>
</h:panelGroup>
----------编辑----------
在通过BalusC的一些建议后，我想我会放弃<p:tree>并找到另一种方式...... :(
您可以通过必要的隐藏输入字段来欺骗它，该字段的值在节点点击时被更改。 您可以使用<p:tree>小部件变量的selections属性以数组形式获取可用选择。
例如
<h:form id="form">
<p:tree widgetVar="tree"
onNodeClick="$('#form:treeSelections').val(tree.selections.length != 0 ? 'ok' : '')">
...
</p:tree>
<h:inputHidden id="treeSelections" required="true"
requiredMessage="Please select at least one tree node" />
<p:message for="treeSelections" />
</h:form>
'ok'值完全是任意的。 重点是隐藏字段已填充，以便required验证器不会被触发。
忍受我，这是一个很长的答案...
由于primefaces树不是EditableValueHolder ，因此无法在JSF生命周期的标准流程验证阶段进行验证（没有发生重大黑客攻击）。 尽我所能，我无法修补primefaces树代码，使其成为EditableValueHolder （树不根据选定的值呈现，而是根据支持树的节点的状态）。 鉴于这些限制，唯一的解决方案是创建我自己的树组件（我没有时间），使用不同的组件（最适合的树），或者在调用应用程序阶段进行验证。
我选择了第三种解决方案，并且尽可能使它与常规验证类似。 主要思想是，使用一个actionListener ，它首先被触发（在任何其他actionListener或主要操作（保存表单）之前被触发来处理验证）。如果验证失败，我向定制属性中的组件添加关于失败的信息，调用facesContext.validationFailed()所以我可以跳过这个动作，然后添加一个preRenderView系统事件监听器，在渲染响应阶段之前根据它们的验证状态修改组件，这样做的方式允许你仍然指定验证使用自定义组件而不是<f:validator> 。下面是代码：
web.xml中：
...
<context-param>
<param-name>javax.faces.FACELETS_LIBRARIES</param-name>
<param-value>/WEB-INF/somenamespace.taglib.xml</param-value>
</context-param>
...
somenamespace.taglib.xml：
<facelet-taglib version="2.0" 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-facelettaglibrary_2_0.xsd">
<namespace>http://ns.my.com/ui/extensions</namespace>
<tag>
<description><![CDATA[
Add an actionListener validator to a component
]]></description>
<tag-name>actionListenerValidator</tag-name>
<handler-class>com.my.ns.actionlistenervalidator.ActionListenerValidatorHandler</handler-class>
<attribute>
<description><![CDATA[
The validatorId.
]]></description>
<name>validatorId</name>
<type>java.lang.String</type>
</attribute>
<attribute>
<description><![CDATA[
A ValueExpression that evaluates to an instance of Validator.
]]></description>
<name>binding</name>
<type>javax.el.ValueExpression</type>
</attribute>
<attribute>
<description><![CDATA[
The styleClass added to the end of the component style class when a validation error occurs
]]></description>
<name>errorStyleClass</name>
<type>java.lang.String</type>
</attribute>
</tag>
</facelet-taglib>
ActionListenerHandler.java：
package com.my.ns.actionlistenervalidator;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.faces.component.UIComponent;
import javax.faces.view.facelets.FaceletContext;
import javax.faces.view.facelets.TagAttribute;
import javax.faces.view.facelets.TagAttributes;
import javax.faces.view.facelets.TagConfig;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.sun.faces.facelets.tag.TagHandlerImpl;
public class ActionListenerValidatorHandler extends TagHandlerImpl {
private static Logger logger = LoggerFactory.getLogger( ActionListenerValidatorHandler.class );
public static enum AttributeKeys {
errorStyleClass("hack.jsf.actionlistenervalidator.errorStyleClass"),
messages("hack.jsf.actionlistenervalidator.messages"),
valid("hack.jsf.actionlistenervalidator.valid"),
validators("hack.jsf.actionlistenervalidator.validators");
private String key;
private AttributeKeys( String key ) {
this.key = key;
}
public String getKey() {
return key;
}
}
public ActionListenerValidatorHandler( TagConfig config ) {
super( config );
}
@Override
public void apply( FaceletContext ctx, UIComponent parent ) throws IOException {
ActionListenerValidatorWrapper validator = new ActionListenerValidatorWrapper( ctx.getFacesContext(),
tagAttributesToMap( ctx, this.tag.getAttributes() ) );
logger.trace( "adding actionListener validator {} to {}", validator, parent );
@SuppressWarnings( "unchecked" )
List<ActionListenerValidatorWrapper> validators = (List<ActionListenerValidatorWrapper>) parent.getAttributes().get( AttributeKeys.validators.getKey() );
if ( validators == null ) {
validators = new ArrayList<ActionListenerValidatorWrapper>();
parent.getAttributes().put( AttributeKeys.validators.getKey(), validators );
}
validators.add( validator );
}
private Map<String, Object> tagAttributesToMap( FaceletContext ctx, TagAttributes tagAttributes ) {
Map<String, Object> map = new HashMap<String, Object>();
for ( TagAttribute attribute : tagAttributes.getAll() ) {
map.put( attribute.getLocalName(), attribute.getValue( ctx ) );
}
return map;
}
}
ActionListenerValidatorWrapper.java：
package com.my.ns.actionlistenervalidator;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Map;
import javax.el.ELContext;
import javax.el.ExpressionFactory;
import javax.el.ValueExpression;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.validator.Validator;
import javax.faces.validator.ValidatorException;
import javax.faces.view.facelets.FaceletException;
import com.sun.faces.el.ELUtils;
public class ActionListenerValidatorWrapper {
private Validator validator;
private String errorStyleClass;
public ActionListenerValidatorWrapper( FacesContext context, Map<String, Object> attributes ) {
String binding = (String) attributes.get( "binding" );
String validatorId = (String) attributes.get( "validatorId" );
if ( binding != null ) {
ExpressionFactory factory = context.getApplication().getExpressionFactory();
ELContext elContext = context.getELContext();
ValueExpression valueExpression = factory.createValueExpression(
elContext, binding, String.class );
this.validator = (Validator) ELUtils.evaluateValueExpression( valueExpression, context.getELContext() );
}
else if ( validatorId != null ) {
this.validator = context.getApplication().createValidator( validatorId );
this.errorStyleClass = (String) attributes.get( "errorStyleClass" );
// inject all attributes
for ( Method method : validator.getClass().getMethods() ) {
String methodName = method.getName();
Class<?>[] types = method.getParameterTypes();
if ( methodName.startsWith( "set" ) && types.length == 1 ) {
String property = Character.toLowerCase( methodName.charAt( 3 ) ) + methodName.substring( 4 );
if ( attributes.containsKey( property ) ) {
// convert value type
Object value = null;
if ( types[0] == Integer.TYPE ) {
value = intValue( context, attributes.get( property ) );
}
else {
value = attributes.get( property );
}
// call setter
try {
method.invoke( validator, value );
}
catch ( IllegalArgumentException e ) {
throw new FaceletException( e );
}
catch ( IllegalAccessException e ) {
throw new FaceletException( e );
}
catch ( InvocationTargetException e ) {
throw new FaceletException( e );
}
}
}
}
}
else {
throw new FaceletException( "ActionListenerValidator requires either validatorId or binding" );
}
}
@Override
public boolean equals( Object otherObj ) {
if ( !(otherObj instanceof ActionListenerValidatorWrapper) ) {
return false;
}
ActionListenerValidatorWrapper other = (ActionListenerValidatorWrapper) otherObj;
return (this.getValidator().equals( other.getValidator() ))
&& (this.getErrorStyleClass().equals( other.getErrorStyleClass() ));
}
public String getErrorStyleClass() {
return errorStyleClass;
}
public Validator getValidator() {
return validator;
}
@Override
public int hashCode() {
int hashCode = (getValidator().hashCode()
+ getErrorStyleClass().hashCode());
return (hashCode);
}
private Integer intValue( FacesContext context, Object value ) {
ExpressionFactory factory = context.getApplication().getExpressionFactory();
ELContext elContext = context.getELContext();
ValueExpression valueExpression = factory.createValueExpression(
elContext, value.toString(), String.class );
if ( !valueExpression.isLiteralText() ) {
return ((Number) ELUtils.evaluateValueExpression( valueExpression, elContext )).intValue();
}
else {
return Integer.valueOf( valueExpression.getExpressionString() );
}
}
@Override
public String toString() {
return validator.getClass().getName();
}
public void validate( FacesContext context, UIComponent component, Object value ) throws ValidatorException {
validator.validate( context, component, value );
}
}
ActionListenerValidatorManager.java：
package com.my.ns.actionlistenervalidator;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.TreeSet;
import javax.faces.application.FacesMessage;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.ManagedProperty;
import javax.faces.bean.ViewScoped;
import javax.faces.component.EditableValueHolder;
import javax.faces.component.UIComponent;
import javax.faces.component.UIViewRoot;
import javax.faces.component.visit.VisitCallback;
import javax.faces.component.visit.VisitContext;
import javax.faces.component.visit.VisitResult;
import javax.faces.context.FacesContext;
import javax.faces.event.ActionEvent;
import javax.faces.event.ComponentSystemEvent;
import javax.faces.validator.ValidatorException;
import com.my.ns.controller.MyBean;
import com.my.ns.actionlistenervalidator.ActionListenerValidatorHandler.AttributeKeys;
import org.primefaces.component.tree.Tree;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
@ManagedBean
@ViewScoped
public class ActionListenerValidatorManager implements Serializable {
private static final long serialVersionUID = -696487579396819893L;
private static Logger logger = LoggerFactory.getLogger( ActionListenerValidatorManager.class );
@ManagedProperty( "#{myBean}" )
private MyBean myBean;
private void addValidationToComponent( Map<String, Object> attributes, Collection<FacesMessage> facesMessages, Set<String> errorStyleClasses ) {
attributes.put( AttributeKeys.valid.getKey(), false );
attributes.put( AttributeKeys.messages.getKey(), facesMessages );
StringBuilder builder = new StringBuilder();
if ( errorStyleClasses != null ) {
for ( String styleClass : errorStyleClasses ) {
builder.append( styleClass );
}
attributes.put( AttributeKeys.errorStyleClass.getKey(), builder.toString() );
}
}
public void applyValidationStateToComponentTreeBecausePrimefacesDidntMakeTreeAnEditableValueHolder( ComponentSystemEvent event ) {
applyValidationStateToComponentTree( FacesContext.getCurrentInstance() );
}
private void applyValidationStateToComponentTree( FacesContext context ) {
UIViewRoot viewRoot = context.getViewRoot();
logger.trace( "pre render view for {}", viewRoot );
viewRoot.visitTree( VisitContext.createVisitContext( context ),
new VisitCallback() {
@Override
public VisitResult visit( VisitContext context, UIComponent component ) {
Map<String, Object> attributes = component.getAttributes();
if ( attributes.containsKey( AttributeKeys.valid.getKey() ) &&
!((Boolean) attributes.get( AttributeKeys.valid.getKey() )) ) {
// validation state
if ( component instanceof EditableValueHolder ) {
((EditableValueHolder) component).setValid( false );
}
// validation messages
FacesContext facesContext = context.getFacesContext();
@SuppressWarnings( "unchecked" )
List<FacesMessage> messages = (List<FacesMessage>) attributes.get( AttributeKeys.messages.getKey() );
if ( messages != null ) {
for ( FacesMessage message : messages ) {
facesContext.addMessage( component.getClientId(), message );
}
}
// style class
String errorStyleClass = (String) attributes.get( AttributeKeys.errorStyleClass.getKey() );
if ( errorStyleClass != null ) {
String styleClass = (String) attributes.get( "styleClass" );
styleClass = styleClass == null ? errorStyleClass : styleClass + " " + errorStyleClass;
attributes.put( "styleClass", styleClass );
}
}
return VisitResult.ACCEPT;
}
} );
}
private void clearValidationFromTree( FacesContext context, UIComponent component ) {
component.visitTree( VisitContext.createVisitContext( context ),
new VisitCallback() {
@Override
public VisitResult visit( VisitContext context, UIComponent target ) {
clearValidationFromComponent( target.getAttributes() );
return VisitResult.ACCEPT;
}
} );
}
private void clearValidationFromComponent( Map<String, Object> attributes ) {
if ( attributes.containsKey( AttributeKeys.validators.getKey() ) ) {
String errorStyleClass = (String) attributes.get( AttributeKeys.errorStyleClass.getKey() );
if ( errorStyleClass != null ) {
String styleClass = (String) attributes.get( "styleClass" );
styleClass = styleClass.replace( errorStyleClass, "" );
attributes.put( "styleClass", styleClass );
}
attributes.remove( AttributeKeys.valid.getKey() );
attributes.remove( AttributeKeys.messages.getKey() );
attributes.remove( AttributeKeys.errorStyleClass.getKey() );
}
}
private Object getValue( FacesContext facesContext, UIComponent component ) {
Object value = null;
if ( component instanceof EditableValueHolder ) {
value = ((EditableValueHolder) component).getValue();
}
else if ( component instanceof Tree ) {
value = myBean.getSelectedIds();
}
return value;
}
public void setMyBean( MyBean myBean ) {
this.myBean = myBean;
}
private void validate( FacesContext context ) {
logger.trace( "entering validation" );
final List<String> validationFailed = new ArrayList<String>();
UIViewRoot viewRoot = context.getViewRoot();
viewRoot.visitTree( VisitContext.createVisitContext( context ),
new VisitCallback() {
@Override
public VisitResult visit( VisitContext context, UIComponent component ) {
if ( !component.isRendered() ) {
// remove all validation from subtree as validation
// is not performed unless the component is
// rendered.
clearValidationFromTree( context.getFacesContext(), component );
return VisitResult.REJECT;
}
Map<String, Object> attributes = component.getAttributes();
if ( attributes.containsKey( AttributeKeys.validators.getKey() ) ) {
Object value = getValue( context.getFacesContext(), component );
boolean valid = true;
Collection<FacesMessage> facesMessages = null;
Set<String> errorStyleClasses = null;
@SuppressWarnings( "unchecked" )
List<ActionListenerValidatorWrapper> validators =
(List<ActionListenerValidatorWrapper>) attributes.get( AttributeKeys.validators.getKey() );
for ( ActionListenerValidatorWrapper validator : validators ) {
try {
validator.validate( context.getFacesContext(), component, value );
}
catch ( ValidatorException validatorException ) {
valid = false;
Collection<FacesMessage> innerMessages = validatorException.getFacesMessages();
if ( innerMessages == null ) {
FacesMessage innerMessage = validatorException.getFacesMessage();
if ( innerMessage != null ) {
innerMessages = Arrays.asList( new FacesMessage[] { innerMessage } );
}
}
if ( facesMessages == null ) {
facesMessages = new ArrayList<FacesMessage>();
}
facesMessages.addAll( innerMessages );
String errorStyleClass = validator.getErrorStyleClass();
if ( errorStyleClass != null ) {
if ( errorStyleClasses == null ) {
errorStyleClasses = new TreeSet<String>();
}
errorStyleClasses.add( errorStyleClass );
}
}
}
if ( valid ) {
// remove previous validation state
clearValidationFromComponent( attributes );
}
else {
// add validation state
addValidationToComponent( attributes, facesMessages, errorStyleClasses );
validationFailed.add( "Yes, it did, but cant update final boolean so we use a list" );
}
}
return VisitResult.ACCEPT;
}
} );
if ( validationFailed.size() > 0 ) {
context.validationFailed();
}
}
public void validateThisFormBecausePrimefacesDidntMakeTreeAnEditableValueHolder( ActionEvent event ) {
validate( FacesContext.getCurrentInstance() );
}
}
最后是使用它的页面：
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:f="http://java.sun.com/jsf/core" xmlns:h="http://java.sun.com/jsf/html"
xmlns:ui="http://java.sun.com/jsf/facelets" xmlns:p="http://primefaces.org/ui"
xmlns:fn="http://java.sun.com/jsp/jstl/functions"
xmlns:myns="http://ns.my.com/ui/extensions">
<h:head />
<h:body>
<f:event type="preRenderView"
listener="#{actionListenerValidatorManager.applyValidationStateToComponentTreeBecausePrimefacesDidntMakeTreeAnEditableValueHolder}" />
...
<h:panelGroup id="treeGroup">
<h:outputLabel for="treeInput"
value="#{i18n['my-tree']}" />
<p:tree id="treeInput"
value="#{myBean.treeRootNode}" var="node"
selectionMode="checkbox"
selection="#{myBean.selectedNodes}">
<pe:actionListenerValidator
validatorId="javax.faces.Required"
errorStyleClass="ui-state-error" />
<p:treeNode>
<h:outputText value="#{node}" />
</p:treeNode>
</p:tree>
</h:panelGroup>
...
</h:body>
</html>
我知道这不是一个剪切/粘贴类型的答案，但它完全概述了这个过程。 这种方法的主要好处是它在使用方式和处理方式上与标准验证相同。 另外它利用现有的验证器。 如果其他人被卡住使用<p:tree>并且必须验证选择，我希望这可以帮助...