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Posted to commits@tapestry.apache.org by bu...@apache.org on 2019/01/25 11:21:25 UTC
svn commit: r1039507 - in /websites/production/tapestry/content:
cache/main.pageCache forms-and-validation.html
Author: buildbot
Date: Fri Jan 25 11:21:24 2019
New Revision: 1039507
Log:
Production update by buildbot for tapestry
Modified:
websites/production/tapestry/content/cache/main.pageCache
websites/production/tapestry/content/forms-and-validation.html
Modified: websites/production/tapestry/content/cache/main.pageCache
==============================================================================
Binary files - no diff available.
Modified: websites/production/tapestry/content/forms-and-validation.html
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--- websites/production/tapestry/content/forms-and-validation.html (original)
+++ websites/production/tapestry/content/forms-and-validation.html Fri Jan 25 11:21:24 2019
@@ -122,11 +122,11 @@
<p> </p><p>Tapestry provides support for creating and rendering forms, populating their fields, and validating user input. For simple cases, input validation is declarative, meaning you simply tell Tapestry what validations to apply to a given field, and it takes care of it on the server and (optionally) on the client as well. In addition, you can provide event handler methods in your page or component classes to handle more complex validation scenarios.</p><p>Finally, Tapestry not only makes it easy to present errors messages to the user, but it can also automatically highlight form fields when validation fails.</p><p><strong>Contents</strong></p><p><style type="text/css">/*<![CDATA[*/
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<ul class="toc-indentation"><li>Related Articles</li></ul>
<ul><li><a href="#FormsandValidation-TheFormComponent">The Form Component</a>
<ul class="toc-indentation"><li><a href="#FormsandValidation-FormEvents">Form Events</a></li><li><a href="#FormsandValidation-HandlingEvents">Handling Events</a></li><li><a href="#FormsandValidation-TrackingValidationErrors">Tracking Validation Errors</a></li><li><a href="#FormsandValidation-StoringDataBetweenRequests">Storing Data Between Requests</a></li><li><a href="#FormsandValidation-ConfiguringFieldsandLabels">Configuring Fields and Labels</a></li></ul>
@@ -135,14 +135,14 @@ div.rbtoc1532344773723 li {margin-left:
<ul class="toc-indentation"><li><a href="#FormsandValidation-CustomizingValidationMessagesforBeanEditForm">Customizing Validation Messages for BeanEditForm</a></li></ul>
</li><li><a href="#FormsandValidation-ConfiguringValidatorContraintsintheMessageCatalog">Configuring Validator Contraints in the Message Catalog</a></li><li><a href="#FormsandValidation-ValidationMacros">Validation Macros</a></li><li><a href="#FormsandValidation-OverridingtheTranslatorwithEvents">Overriding the Translator with Events</a></li></ul>
</li></ul></div><h1 id="FormsandValidation-TheFormComponent">The Form Component</h1><p>The core of Tapestry's form support is the <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Form.html">Form</a> component. The Form component encloses (wraps around) all the other <em>field components</em> such as <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/TextField.html">TextField</a>, <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/TextArea.html">TextArea</a>, <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/Checkbox.html">Checkbox</a>, etc.</p><h2 id="FormsandValidation-FormEvents">Form Events</h2><p>The Form component emits a number of <a href="component-events.html">component events</a>. You'll want to provide event handler m
ethods for some of these.</p><p>When rendering, the Form component emits two events: first, "prepareForRender", then "prepare". These allow the Form's container to set up any fields or properties that will be referenced in the form. For example, this is a good place to create a temporary entity object to be rendered, or to load an entity from a database to be edited.</p><p>When user submits the form on the client, a series of steps occur on the server.</p><p>First, the Form emits a "prepareForSubmit" event, then a "prepare" event. These allow the container to ensure that objects are set up and ready to receive information from the form submission.</p><p>Next, all the fields inside the form are <em>activated</em> to pull values out of the incoming request, validate them and (if valid) store the changes.</p><div class="navmenu" style="float:right; width:25%; background:#eee; margin:3px; padding:3px">
-<p><em>For Tapestry 4 Users:</em> Tapestry 5 does not use the fragile "form rewind" approach from Tapestry 4. Instead, a hidden field generated during the render stores the information needed to process the form submission.</p></div> <p>After the fields have done their processing, the Form emits a "validate" event. This is your chance to perform any cross-form validation that can't be described declaratively.</p><p>Next, the Form determines if there have been any validation errors. If there have been, then the submission is considered a failure, and a "failure" event is emitted. If there have been no validation errors, then a "success" event is emitted.</p><p>Finally, the Form emits a "submit" event, for logic that doesn't care about success or failure.</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Form Event (in order)</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Phase</p></th><th colspan
="1" rowspan="1" class="confluenceTh"><p>When emitted (and typical use)</p></th><th colspan="1" rowspan="1" class="confluenceTh">Method Name</th><th colspan="1" rowspan="1" class="confluenceTh">@OnEvent Constant</th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>prepareForRender</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Render</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Before rendering the form (e.g. load an entity from a database to be edited)</p></td><td colspan="1" rowspan="1" class="confluenceTd">onPrepareForRender()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.PREPARE_FOR_RENDER</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>prepare</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Render</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Before rendering the form, but after <em>prepareForRender</em></p></td><td colspan="1" rowspan="1" c
lass="confluenceTd">onPrepare()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.PREPARE</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>prepareForSubmit</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Submit</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Before the submitted form is processed</p></td><td colspan="1" rowspan="1" class="confluenceTd">onPrepareForSubmit()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.PREPARE_FOR_SUBMIT</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>prepare</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Submit</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Before the submitted form is processed, but after <em>prepareForSubmit</em></p></td><td colspan="1" rowspan="1" class="confluenceTd">onPrepare()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.PREPARE</td></tr><tr><td cols
pan="1" rowspan="1" class="confluenceTd"><p><strong>validate</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Submit</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>After fields have been populated from submitted values and validated (e.g. perform cross-field validation)</p></td><td colspan="1" rowspan="1" class="confluenceTd">onValidate</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.VALIDATE</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>validateForm</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Submit</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>same as <em>validate (deprecated – do not use)<br clear="none"></em></p></td><td colspan="1" rowspan="1" class="confluenceTd"><em>onValidateForm</em></td><td colspan="1" rowspan="1" class="confluenceTd"> </td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>failure</strong></p></td><td colspan=
"1" rowspan="1" class="confluenceTd"><p>Submit</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>After one or more validation errors have occurred</p></td><td colspan="1" rowspan="1" class="confluenceTd">onFailure()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.FAILURE</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>success</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Submit</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>When validation has completed <em>without</em> any errors (e.g. save changes to the database)</p></td><td colspan="1" rowspan="1" class="confluenceTd">onSuccess()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.SUCCESS</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>submit</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Submit</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>After all validation (s
uccess or failure) has finished</p></td><td colspan="1" rowspan="1" class="confluenceTd">onSubmit()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.SUBMIT</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><strong>canceled</strong></td><td colspan="1" rowspan="1" class="confluenceTd">Submit</td><td colspan="1" rowspan="1" class="confluenceTd">Whenever a <em>Submit</em> or <em>LinkSubmit</em> component containing <em>mode="cancel"</em> or <em>mode="unconditional"</em> is clicked</td><td colspan="1" rowspan="1" class="confluenceTd">onCanceled()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.CANCELED</td></tr></tbody></table></div><p>Note that the "prepare" event is emitted during both form rendering and form submission.</p><h2 id="FormsandValidation-HandlingEvents">Handling Events</h2><p>Main Article: <a href="component-events.html">Component Events</a></p><p>You handle events by providing methods in your page or component class, ei
ther following the on<strong><em>Event</em></strong>From<strong><em>Component</em></strong>() naming convention or using the OnEvent annotation. For example:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Event Handler Using Naming Convention</b></div><div class="codeContent panelContent pdl">
+<p><em>For Tapestry 4 Users:</em> Tapestry 5 does not use the fragile "form rewind" approach from Tapestry 4. Instead, a hidden field generated during the render stores the information needed to process the form submission.</p></div> <p><br clear="none"></p><p>After the fields have done their processing, the Form emits a "validate" event. This is your chance to perform any cross-form validation that can't be described declaratively.</p><p>Next, the Form determines if there have been any validation errors. If there have been, then the submission is considered a failure, and a "failure" event is emitted. If there have been no validation errors, then a "success" event is emitted.</p><p>Finally, the Form emits a "submit" event, for logic that doesn't care about success or failure.</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Form Event (in order)</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>P
hase</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>When emitted (and typical use)</p></th><th colspan="1" rowspan="1" class="confluenceTh">Method Name</th><th colspan="1" rowspan="1" class="confluenceTh">@OnEvent Constant</th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>prepareForRender</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Render</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Before rendering the form (e.g. load an entity from a database to be edited)</p></td><td colspan="1" rowspan="1" class="confluenceTd">onPrepareForRender()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.PREPARE_FOR_RENDER</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>prepare</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Render</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Before rendering the form, but after <em>prepareForRender</em></p></td><td c
olspan="1" rowspan="1" class="confluenceTd">onPrepare()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.PREPARE</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>prepareForSubmit</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Submit</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Before the submitted form is processed</p></td><td colspan="1" rowspan="1" class="confluenceTd">onPrepareForSubmit()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.PREPARE_FOR_SUBMIT</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>prepare</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Submit</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Before the submitted form is processed, but after <em>prepareForSubmit</em></p></td><td colspan="1" rowspan="1" class="confluenceTd">onPrepare()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.PREPA
RE</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>validate</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Submit</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>After fields have been populated from submitted values and validated (e.g. perform cross-field validation)</p></td><td colspan="1" rowspan="1" class="confluenceTd">onValidate</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.VALIDATE</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>validateForm</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Submit</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>same as <em>validate (deprecated – do not use)<br clear="none"></em></p></td><td colspan="1" rowspan="1" class="confluenceTd"><em>onValidateForm</em></td><td colspan="1" rowspan="1" class="confluenceTd"> </td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>failure</stro
ng></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Submit</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>After one or more validation errors have occurred</p></td><td colspan="1" rowspan="1" class="confluenceTd">onFailure()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.FAILURE</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>success</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Submit</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>When validation has completed <em>without</em> any errors (e.g. save changes to the database)</p></td><td colspan="1" rowspan="1" class="confluenceTd">onSuccess()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.SUCCESS</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p><strong>submit</strong></p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Submit</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p
>After all validation (success or failure) has finished</p></td><td colspan="1" rowspan="1" class="confluenceTd">onSubmit()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.SUBMIT</td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><strong>canceled</strong></td><td colspan="1" rowspan="1" class="confluenceTd">Submit</td><td colspan="1" rowspan="1" class="confluenceTd">Whenever a <em>Submit</em> or <em>LinkSubmit</em> component containing <em>mode="cancel"</em> or <em>mode="unconditional"</em> is clicked</td><td colspan="1" rowspan="1" class="confluenceTd">onCanceled()</td><td colspan="1" rowspan="1" class="confluenceTd">EventConstants.CANCELED</td></tr></tbody></table></div><p>Note that the "prepare" event is emitted during both form rendering and form submission.</p><h2 id="FormsandValidation-HandlingEvents">Handling Events</h2><p>Main Article: <a href="component-events.html">Component Events</a></p><p>You handle events by providing methods in your pag
e or component class, either following the on<strong><em>Event</em></strong>From<strong><em>Component</em></strong>() naming convention or using the OnEvent annotation. For example:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Event Handler Using Naming Convention</b></div><div class="codeContent panelContent pdl">
<pre class="syntaxhighlighter-pre" data-syntaxhighlighter-params="brush: java; gutter: false; theme: Default" data-theme="Default"> void onValidateFromPassword() { ...}</pre>
</div></div><p>or the equivalent using @OnEvent:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Event Handler Using @OnEvent Annotation</b></div><div class="codeContent panelContent pdl">
<pre class="syntaxhighlighter-pre" data-syntaxhighlighter-params="brush: java; gutter: false; theme: Default" data-theme="Default"> @OnEvent(value=EventConstants.VALIDATE, component="password")
void verifyThePassword() { ...}</pre>
-</div></div><h2 id="FormsandValidation-TrackingValidationErrors">Tracking Validation Errors</h2><p>Associated with the Form is a <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/ValidationTracker.html">ValidationTracker</a> that tracks all the provided user input and validation errors for every field in the form. The tracker can be provided to the Form via the Form's tracker parameter, but this is rarely necessary.</p><p>The Form includes methods <code>isValid()</code> and <code>getHasErrors()</code>, which are used to see if the Form's validation tracker contains any errors.</p><p>In your own logic, it is possible to record your own errors. Form includes two different versions of method <code>recordError()</code>, one of which specifies a <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/Field.html">Field</a> (an interface implemented by all form element components), and one of which is for
"global" errors, not associated with any particular field. If the error concerns only a single field, you should use the first version so that the field will be highlighted.</p><h2 id="FormsandValidation-StoringDataBetweenRequests">Storing Data Between Requests</h2><p></p><div class="navmenu" style="float:right; width:40%; background:white; margin:3px; padding:3px">
+</div></div><h2 id="FormsandValidation-TrackingValidationErrors">Tracking Validation Errors</h2><p>Associated with the Form is a <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/ValidationTracker.html">ValidationTracker</a> that tracks all the provided user input and validation errors for every field in the form. The tracker can be provided to the Form via the Form's tracker parameter, but this is rarely necessary.</p><p>The Form includes methods <code>isValid()</code> and <code>getHasErrors()</code>, which are used to see if the Form's validation tracker contains any errors.</p><p>In your own logic, it is possible to record your own errors. Form includes two different versions of method <code>recordError()</code>, one of which specifies a <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/Field.html">Field</a> (an interface implemented by all form element components), and one of which is for
"global" errors, not associated with any particular field. If the error concerns only a single field, you should use the first version so that the field will be highlighted.</p><h2 id="FormsandValidation-StoringDataBetweenRequests">Storing Data Between Requests</h2><p><br clear="none"></p><div class="navmenu" style="float:right; width:40%; background:white; margin:3px; padding:3px">
<div class="confluence-information-macro confluence-information-macro-information"><p class="title">New in Tapestry 5.4</p><span class="aui-icon aui-icon-small aui-iconfont-info confluence-information-macro-icon"></span><div class="confluence-information-macro-body">
-<p>Starting in Tapestry 5.4, the default behavior for server-side validation failures is to re-render the page within the same request (rather than emitting a redirect). This removes the need to use a session-persistent field to store the validation tracker when validation failures occur.</p></div></div></div>As with other action requests, the result of a form submission (except when using <a href="forms-and-validation.html">Zones</a>) is to send a redirect to the client, which results in a second request (to re-render the page). The ValidationTracker must be <a href="persistent-page-data.html">persisted</a> (generally in the HttpSession) across these two requests in order to prevent the loss of validation information. Fortunately, the default ValidationTracker provided by the Form component is persistent, so you don't normally have to worry about it.<p>However, for the same reason, the individual fields updated by the components should also be persisted across requests, and this
is something you <strong>do</strong> need to do yourself – generally with the @Persist annotation.</p><p>For example, a Login page class, which collects a user name and a password, might look like:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Login.java Example</b></div><div class="codeContent panelContent pdl">
+<p>Starting in Tapestry 5.4, the default behavior for server-side validation failures is to re-render the page within the same request (rather than emitting a redirect). This removes the need to use a session-persistent field to store the validation tracker when validation failures occur.</p></div></div></div>As with other action requests, the result of a form submission (except when using <a href="forms-and-validation.html">Zones</a>) is to send a redirect to the client, which results in a second request (to re-render the page). The ValidationTracker must be <a href="persistent-page-data.html">persisted</a> (generally in the HttpSession) across these two requests in order to prevent the loss of validation information. Fortunately, the default ValidationTracker provided by the Form component is persistent, so you don't normally have to worry about it.<p><br clear="none"></p><p>However, for the same reason, the individual fields updated by the components should also be persisted ac
ross requests, and this is something you <strong>do</strong> need to do yourself – generally with the @Persist annotation.</p><p>For example, a Login page class, which collects a user name and a password, might look like:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Login.java Example</b></div><div class="codeContent panelContent pdl">
<pre class="syntaxhighlighter-pre" data-syntaxhighlighter-params="brush: java; gutter: false; theme: Default" data-theme="Default">package com.example.newapp.pages;
@@ -190,9 +190,9 @@ public class Login {
</pre>
-</div></div><p></p><div class="navmenu" style="float:right; width:40%; background:white; margin:3px; padding:3px">
+</div></div><p><br clear="none"></p><div class="navmenu" style="float:right; width:40%; background:white; margin:3px; padding:3px">
<div class="confluence-information-macro confluence-information-macro-information"><span class="aui-icon aui-icon-small aui-iconfont-info confluence-information-macro-icon"></span><div class="confluence-information-macro-body">
-<p>Note that the onValidateFromLoginForm() and onSuccess() methods are not public; event handler methods can have any visibility, even private. Package private (that is, no modifier) is the typical use, as it allows the component to be tested, from a test case class in the same package.</p></div></div></div>Because a form submission is really <em>two</em> requests: the submission itself (which results in a redirect response), then a second request for the page (which results in a re-rendering of the page), it is necessary to persist the userName field between the two requests, by using the @Persist annotation. This would be necessary for the password field as well, except that the <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/PasswordField.html">PasswordField</a> component never renders a value.<div class="confluence-information-macro confluence-information-macro-tip"><span class="aui-icon aui-icon-small aui-iconfo
nt-approve confluence-information-macro-icon"></span><div class="confluence-information-macro-body"><p>To avoid data loss, fields whose values are stored in the HttpSession (such as userName, above) must be serializable, particularly if you want to be able to cluster your application or preserve sessions across server restarts.</p></div></div><p>The Form only emits a "success" event if the there are no prior validation errors. This means it is not necessary to write <code>if (form.getHasErrors()) return;</code> as the first line of the method.</p><p>Finally, notice how business logic fits into validation. The UserAuthenticator service is responsible for ensuring that the userName and (plaintext) password are valid. When it returns false, we ask the Form component to record an error. We provide the PasswordField instance as the first parameter; this ensures that the password field, and its label, are decorated when the Form is re-rendered, to present the errors to the user.</p><h2 id
="FormsandValidation-ConfiguringFieldsandLabels">Configuring Fields and Labels</h2><p>The Login page template below contains a minimal amount of Tapestry instrumentation and references some of the <a class="external-link" href="http://getbootstrap.com" rel="nofollow">Bootstrap</a> CSS classes (Bootstrap is automatically integrated into each page by default, starting with Tapestry 5.4).</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Login.tml Example</b></div><div class="codeContent panelContent pdl">
+<p>Note that the onValidateFromLoginForm() and onSuccess() methods are not public; event handler methods can have any visibility, even private. Package private (that is, no modifier) is the typical use, as it allows the component to be tested, from a test case class in the same package.</p></div></div></div>Because a form submission is really <em>two</em> requests: the submission itself (which results in a redirect response), then a second request for the page (which results in a re-rendering of the page), it is necessary to persist the userName field between the two requests, by using the @Persist annotation. This would be necessary for the password field as well, except that the <a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/corelib/components/PasswordField.html">PasswordField</a> component never renders a value.<p><br clear="none"></p><div class="confluence-information-macro confluence-information-macro-tip"><span class="aui-icon a
ui-icon-small aui-iconfont-approve confluence-information-macro-icon"></span><div class="confluence-information-macro-body"><p>To avoid data loss, fields whose values are stored in the HttpSession (such as userName, above) must be serializable, particularly if you want to be able to cluster your application or preserve sessions across server restarts.</p></div></div><p>The Form only emits a "success" event if the there are no prior validation errors. This means it is not necessary to write <code>if (form.getHasErrors()) return;</code> as the first line of the method.</p><p>Finally, notice how business logic fits into validation. The UserAuthenticator service is responsible for ensuring that the userName and (plaintext) password are valid. When it returns false, we ask the Form component to record an error. We provide the PasswordField instance as the first parameter; this ensures that the password field, and its label, are decorated when the Form is re-rendered, to present the error
s to the user.</p><h2 id="FormsandValidation-ConfiguringFieldsandLabels">Configuring Fields and Labels</h2><p>The Login page template below contains a minimal amount of Tapestry instrumentation and references some of the <a class="external-link" href="http://getbootstrap.com" rel="nofollow">Bootstrap</a> CSS classes (Bootstrap is automatically integrated into each page by default, starting with Tapestry 5.4).</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>Login.tml Example</b></div><div class="codeContent panelContent pdl">
<pre class="syntaxhighlighter-pre" data-syntaxhighlighter-params="brush: xml; gutter: false; theme: Default" data-theme="Default"><html t:type="layout" title="newapp com.example"
xmlns:t="http://tapestry.apache.org/schema/tapestry_5_4.xsd">
@@ -217,7 +217,7 @@ public class Login {
</div></div><p> </p><h1 id="FormsandValidation-FormValidation"><span style="color: rgb(83,145,38);">Form Validation</span></h1><p>The above example is a very basic form which allows the fields to be empty. However, with a little more effort we can add client-side validation to prevent the user from submitting the form with either field empty.</p><p>Validation in Tapestry involves associating one or more <em>validators</em> with a form element component, such as TextField or PasswordField. This is done using the <strong>validate</strong> parameter:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<pre class="syntaxhighlighter-pre" data-syntaxhighlighter-params="brush: xml; gutter: false; theme: Default" data-theme="Default"><t:textfield t:id="userName" validate="required" t:mixins="formgroup"/>
<t:passwordfield t:id="password" value="password" validate="required" t:mixins="formgroup"/></pre>
-</div></div><h2 id="FormsandValidation-AvailableValidators"><span style="color: rgb(83,145,38);">Available Validators</span></h2><p>Tapestry provides the following built-in validators:</p><div class="table-wrap"><table class="confluenceTable"><tbody><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Validator</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Constraint Type</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Description</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Example</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>email</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>–</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Ensures that the given input looks like a valid e-mail address</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value="userEmail" validate="email" /></code></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>
max</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>long</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Enforces a maximum integer value</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value="age" validate="max=120,min=0" /></code></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>maxLength</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>int</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Makes sure that a string value has a maximum length</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value="zip" validate="maxlength=7" /></code></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>min</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>long</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Enforces a minimum integer value</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value
="age" validate="max=120,min=0" /></code></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>minLength</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>int</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Makes sure that a string value has a minimum length</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value="somefield" validate="minlength=1" /></code></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>none</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>–</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Does nothing (used to override a @Validate annotation)</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value="somefield" validate="none" /></code></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>regexp</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>pattern</p></td><td colspan="1" rowspan
="1" class="confluenceTd"><p>Makes sure that a string value conforms to a given pattern</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value="letterfield" validate="regexp=^</code><code>[A-Za-z]+$" /></code></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>required</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>–</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Makes sure that a string value is not null and not the empty string</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value="name" validate="required" /></code></p></td></tr></tbody></table></div><h2 id="FormsandValidation-CentralizingValidationwith@Validate">Centralizing Validation with @Validate</h2><p>The @<a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/beaneditor/Validate.html">Validate</a> annotation can take the place of the validate parameter of TextF
ield, PasswordField, TextArea and other components. When the validate parameter is not bound in the template file, the component will check for the @Validate annotation and use its value as the validation definition.</p><p>The annotation may be placed on the getter or setter method, or on the field itself.</p><p>Let's update the two fields of the Login page:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div><h2 id="FormsandValidation-AvailableValidators"><span style="color: rgb(83,145,38);">Available Validators</span></h2><p>Tapestry provides the following built-in validators:</p><div class="table-wrap"><table class="confluenceTable"><colgroup span="1"><col span="1"><col span="1"><col span="1"><col span="1"></colgroup><tbody><tr><th colspan="1" rowspan="1" class="confluenceTh"><p>Validator</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Constraint Type</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Description</p></th><th colspan="1" rowspan="1" class="confluenceTh"><p>Example</p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>email</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>–</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Ensures that the given input looks like a valid e-mail address</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value="userEmail" validate="ema
il" /></code></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>max</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>long</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Enforces a maximum integer value</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value="age" validate="max=120,min=0" /></code></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>maxLength</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>int</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Makes sure that a string value has a maximum length</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value="zip" validate="maxlength=7" /></code></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>min</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>long</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Enforces a minimum integer value</
p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value="age" validate="max=120,min=0" /></code></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>minLength</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>int</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Makes sure that a string value has a minimum length</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value="somefield" validate="minlength=1" /></code></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>none</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>–</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Does nothing (used to override a @Validate annotation)</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value="somefield" validate="none" /></code></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>regexp</p></td><td c
olspan="1" rowspan="1" class="confluenceTd"><p>pattern</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Makes sure that a string value conforms to a given pattern</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value="letterfield" validate="regexp=^</code><code>[A-Za-z]+$" /></code></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p>required</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>–</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p>Makes sure that a string value is not null and not the empty string</p></td><td colspan="1" rowspan="1" class="confluenceTd"><p><code><t:textfield value="name" validate="required" /></code></p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd">checked <em>(Since 5.4.5)</em></td><td colspan="1" rowspan="1" class="confluenceTd">boolean</td><td colspan="1" rowspan="1" class="confluenceTd">Makes sure that the boolean is true (checkbox is che
cked)</td><td colspan="1" rowspan="1" class="confluenceTd"><t:Checkbox value="value" validate="checked" /></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd">unchecked <em>(Since 5.4.5)</em></td><td colspan="1" rowspan="1" class="confluenceTd">boolean</td><td colspan="1" rowspan="1" class="confluenceTd"><span>Makes sure that the boolean is false (checkbox is unchecked)</span></td><td colspan="1" rowspan="1" class="confluenceTd"><t:Checkbox value="value" validate="unchecked" /></td></tr></tbody></table></div><h2 id="FormsandValidation-CentralizingValidationwith@Validate">Centralizing Validation with @Validate</h2><p>The @<a class="external-link" href="http://tapestry.apache.org/current/apidocs/org/apache/tapestry5/beaneditor/Validate.html">Validate</a> annotation can take the place of the validate parameter of TextField, PasswordField, TextArea and other components. When the validate parameter is not bound in the template file, the component will check for the
@Validate annotation and use its value as the validation definition.</p><p>The annotation may be placed on the getter or setter method, or on the field itself.</p><p>Let's update the two fields of the Login page:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<pre class="syntaxhighlighter-pre" data-syntaxhighlighter-params="brush: java; gutter: false; theme: Default" data-theme="Default"> @Persist
@Property
@Validate("required")
@@ -230,7 +230,7 @@ public class Login {
<pre class="syntaxhighlighter-pre" data-syntaxhighlighter-params="brush: xml; gutter: false; theme: Default" data-theme="Default"><t:textfield validate="email,required" .../></pre>
</div></div><p>then the output HTML will look like this:</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<pre class="syntaxhighlighter-pre" data-syntaxhighlighter-params="brush: xml; gutter: false; theme: Default" data-theme="Default"><input type="email" required ...></pre>
-</div></div><p>which causes modern browsers to present a validation error message whenever text is entered that doesn't look like an email address, or if the field is left blank.</p><p>The browser's built-in validation is performed <em>before</em> Tapestry's own client-side validation. This is so that older browsers will still perform client-side validation as expected.</p><p>The following behaviors are included:</p><ul><li>The "<strong>required</strong>" validator adds the "required" attribute to the rendered HTML</li><li>The "<strong>regexp</strong>" validator adds the "pattern" attribute to the rendered HTML</li><li>The "<strong>email</strong>" validator sets the <code>type</code> attribute to "email" in the rendered HTML</li><li>The "<strong>min</strong>" validator sets the <code>type</code> attribute to "number" and adds the "min" attribute in the rendered HTML</li><li>The "<strong>max</strong>" validator sets the <code>type</code> attribute to "number" and adds the "max"
attribute in the rendered HTML</li><li>When bound to a <strong>number</strong> type, the TextField component sets the <code>type</code> attribute to "number" in the rendered HTML</li></ul><h2 id="FormsandValidation-ServerSideValidation">Server Side Validation</h2><p>Some validation can't, or shouldn't, be done on the client side. How do we know if the password is correct? Short of downloading all users and passwords to the client, we really need to do the validation on the server.</p><p>In fact, all client-side validation (via the validate parameter, or @Validate annotation) is performed again on the server.</p><p>It is also possible to perform extra validation there.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
+</div></div><p>which causes modern browsers to present a validation error message whenever text is entered that doesn't look like an email address, or if the field is left blank.</p><p>The browser's built-in validation is performed <em>before</em> Tapestry's own client-side validation. This is so that older browsers will still perform client-side validation as expected.</p><p>The following behaviors are included:</p><ul><li>The "<strong>required</strong>" validator adds the "required" attribute to the rendered HTML</li><li><p class="auto-cursor-target">The "<strong>checked</strong>" validator adds the "required" attribute to the rendered HTML  <em>(Since 5.4.5)</em></p></li><li>The "<strong>regexp</strong>" validator adds the "pattern" attribute to the rendered HTML</li><li>The "<strong>email</strong>" validator sets the <code>type</code> attribute to "email" in the rendered HTML</li><li>The "<strong>min</strong>" validator sets the <code>type</code> attribute to "number"
and adds the "min" attribute in the rendered HTML</li><li>The "<strong>max</strong>" validator sets the <code>type</code> attribute to "number" and adds the "max" attribute in the rendered HTML</li><li>When bound to a <strong>number</strong> type, the TextField component sets the <code>type</code> attribute to "number" in the rendered HTML</li></ul><h2 id="FormsandValidation-ServerSideValidation">Server Side Validation</h2><p>Some validation can't, or shouldn't, be done on the client side. How do we know if the password is correct? Short of downloading all users and passwords to the client, we really need to do the validation on the server.</p><p>In fact, all client-side validation (via the validate parameter, or @Validate annotation) is performed again on the server.</p><p>It is also possible to perform extra validation there.</p><div class="code panel pdl" style="border-width: 1px;"><div class="codeContent panelContent pdl">
<pre class="syntaxhighlighter-pre" data-syntaxhighlighter-params="brush: java; gutter: false; theme: Default" data-theme="Default"> /**
* Do the cross-field validation
*/