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<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>What's new in Thymeleaf 2.1 - Thymeleaf: java XML/XHTML/HTML5 template engine</title>
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<a href="index.html">thymeleaf</a>
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<a href="documentation.html">documentation</a>
::
<span class="current">what's new in thymeleaf 2.1</span>
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<div id="content">
<h1>What's new in Thymeleaf 2.1</h1>
<p>
Thymeleaf 2.1 includes a lot of new powerful features. Here they are:
</p>
<ul>
<li><a href="#core"><strong>New Features in Thymeleaf Core</strong></a>:
<ul>
<li>Fragment inclusion:
<ul>
<li><a href="#stf">Same-template fragments</a></li>
<li><a href="#fsig">Parameterizable fragment signatures</a></li>
</ul>
</li>
<li>Expression improvements:
<ul>
<li><a href="#doms">More powerful DOM selector syntax</a></li>
<li><a href="#littok">Literal tokens</a></li>
<li><a href="#bnlit">Boolean and null literals</a></li>
<li><a href="#lsub">Literal substitutions</a></li>
<li><a href="#pru">Protocol-relative URLs</a></li>
</ul>
</li>
<li>Markup processing improvements:
<ul>
<li><a href="#plcom">Parser-level comment blocks</a></li>
<li><a href="#pocb">Prototype-only comment blocks</a></li>
</ul>
</li>
<li>New Standard Dialect features:
<ul>
<li><a href="#remove">Improved <kbd>th:remove</kbd> attribute</a></li>
<li><a href="#bloc">Synthetic <kbd>th:block</kbd> tag</a></li>
<li><a href="#data">Support for HTML5-friendly attribute and element names</a></li>
<li><a href="#assr">New <kbd>th:assert</kbd> for in-template assertions</a></li>
<li><a href="#repl">New <kbd>th:replace</kbd> as a synonym of <kbd>th:substituteby</kbd></a></li>
<li><a href="#with">Reuse variables in <kbd>th:with</kbd></a></li>
</ul>
</li>
</ul>
</li>
<li><a href="#spring"><strong>New Features in Spring Integration</strong></a>:
<ul>
<li>Better integration with Spring features:
<ul>
<li><a href="#spbean">More integrated acccess to beans from expressions</a></li>
<li><a href="#spconv">Integration of Spring type conversion infrastructure</a></li>
<li><a href="#spres">Spring-resource based template resolver</a></li>
</ul>
</li>
<li>Ease of use:
<ul>
<li><a href="#spfrag">Render view fragments directly from controllers</a></li>
</ul>
</li>
<li>Form error handling:
<ul>
<li><a href="#errcl">New <kbd>th:errorclass</kbd> for adding CSS class to form fields in error</a></li>
<li><a href="#sperr">Additional form validation error reporting options</a></li>
</ul>
</li>
<li>Security:
<ul>
<li><a href="#reqdata">Transparent integration with Spring's <kbd>RequestDataValueProcessor</kbd></a></li>
</ul>
</li>
</ul>
</li>
</ul>
<h1><a name="core"></a>New Features in Thymeleaf Core</h1>
<h2><a name="stf"></a>Same-template fragments</h2>
<p>
Thymeleaf now allows including fragments from the same template. There are two available
syntaxes: one specifying no template name:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:include="::fragment_name">...</div>
]]></script>
<p>
...and another one specifying the keyword <kbd>this</kbd>:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:include="this :: fragment_name">...</div>
]]></script>
<h2><a name="fsig"></a>Parameterizable fragment signatures</h2>
<p>
In order to create a more <i>function-like</i> mechanism for the use of template fragments, fragments
defined with <kbd>th:fragment</kbd> can now specify a set of parameters:
</p>
<script type="syntaxhighlighter" class="brush:html"><![CDATA[
<div th:fragment="frag (onevar,twovar)">
<p th:text="${onevar} + ' - ' + ${twovar}">...</p>
</div>
]]></script>
<p>
This requires the use of one of these two syntaxes to call the fragment from <kbd>th:include</kbd>,
<kbd>th:substituteby</kbd> or <kbd>th:replace</kbd>:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:include="::frag (${value1},${value2})">...</div>
]]></script>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:include="::frag (onevar=${value1},twovar=${value2})">...</div>
]]></script>
<p>
Note that order is not important in the last option:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:include="::frag (twovar=${value2},onevar=${value1})">...</div>
]]></script>
<h4>Fragment local variables without fragment signature</h4>
<p>
Even if fragments are defined without signature, like this:
</p>
<script type="syntaxhighlighter" class="brush:html"><![CDATA[
<div th:fragment="frag">
...
</div>
]]></script>
<p>
We could use the second syntax specified above to call them (and only the second one):
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:include="::frag (onevar=${value1},twovar=${value2})">
]]></script>
<p>
This would be, in fact, equivalent to a combination of <kbd>th:include</kbd> and <kbd>th:with</kbd>:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:include="::frag" th:with="onevar=${value1},twovar=${value2}">
]]></script>
<p>
But the difference is, this will also work with <kbd>th:substituteby</kbd> (and the new <kbd>th:replace</kbd>).
Until now these attributes didn't work well with <kbd>th:with</kbd> because they effectively removed the host
tag before <kbd>th:with</kbd> got executed:
</p>
<script type="syntaxhighlighter" class="brush:html"><![CDATA[
<!-- th:with will never be executed. Variables will never be created -->
<div th:replace="::frag" th:with="onevar=${value1},twovar=${value2}">
]]></script>
<p>
<strong>Note</strong> that this specification of local variables for a fragment —no matter whether it
has a signature or not— does not cause an initialization of the context to zero.
Fragments will still be able to access every context variable being used at the calling
template like they currently are.
</p>
<h2><a name="doms"></a>More powerful DOM selector syntax</h2>
<p>
DOM Selector syntax has been enhanced to include more selection possibilities and easier
selection of DOM fragments. These selectors are a way to specify fragments already available since
thymeleaf 2.0:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:include="mytemplate :: [//div[@class='content']]">...</div>
]]></script>
<p>
Thymeleaf 2.1 adds to these Selectors some syntax features borrowed from CSS and jQuery, in order to make them
more powerful and easy to use:
</p>
<ul>
<li>Now <kbd>x</kbd> is exactly equivalent to <kbd>//x</kbd> (search an element with name or <em>reference</em> "<kbd>x</kbd>"
at any depth level).</li>
<li>Allowed selectors without element name/reference, as long as it includes a specification of arguments. So
<kbd>[@class='oneclass']</kbd> is now a valid selector that looks for any elements (<em>tags</em>) with a
<kbd>class</kbd> attribute with value <kbd>"oneclass"</kbd>.</li>
<li>Attribute selection enhancements:
<ul>
<li>Besides "<kbd>=</kbd>" (equal)., other comparison operators are now also valid: "<kbd>!=</kbd>" (not equal),
"<kbd>^=</kbd>" (starts with) and "<kbd>$=</kbd>" (ends with). For example:
<kbd>x[@class^='section']</kbd> means <em>elements with name <kbd>x</kbd> and a value for
attribute class that starts with <kbd>section</kbd></em>.</li>
<li>Attributes can be specified both starting with <kbd>@</kbd> (XPath-style) and without
(jQuery-style). So <kbd>x[z='v']</kbd> is now equivalent to <kbd>x[@z='v']</kbd>.</li>
<li>Multiple-attribute modifiers can now be joined both with "<kbd>and</kbd>" (XPath-style) and also by
chaining multiple modifiers (jQuery-style). So <kbd>x[@z1='v1' and @z2='v2']</kbd> is
actually equivalent to <kbd>x[@z1='v1'][@z2='v2']</kbd> (and also to
<kbd>x[z1='v1'][z2='v2']</kbd>).</li>
</ul>
</li>
<li>Direct selectors:
<ul>
<li><kbd>x.oneclass</kbd> is now equivalent to <kbd>x[class='oneclass']</kbd>.</li>
<li><kbd>.oneclass</kbd> is now equivalent to <kbd>[class='oneclass']</kbd>.</li>
<li><kbd>x#oneid</kbd> is now equivalent to <kbd>x[id='oneid']</kbd>.</li>
<li><kbd>#oneid</kbd> is now equivalent to <kbd>[id='oneid']</kbd>.</li>
<li><kbd>x%oneref</kbd> means nodes -not just <em>elements</em>- with name <kbd>x</kbd> that match reference
<kbd>oneref</kbd> according to a specified <kbd>DOMSelector.INodeReferenceChecker</kbd> implementation.</li>
<li><kbd>%oneref</kbd> means nodes -not just <em>elements</em>- with any name that match reference
<kbd>oneref</kbd> according to a specified <kbd>DOMSelector.INodeReferenceChecker</kbd> implementation.
<ul>
<li>Note this is actually equivalent to simply <kbd>oneref</kbd> because references can be used instead of element names.</li>
</ul>
</li>
<li>Direct selectors and attribute selectors can be mixed: <kbd>a.external[@href^='https']</kbd>.</li>
</ul>
</li>
<li>Specific feature: DOM Selectors now understand the <kbd>class</kbd> attribute to be multivalued, and therefore allow the
application of selectors on this attribute even if the element has several class values.
For example, <kbd>div[class='two']</kbd> will match <kbd><div class="one two three"/><kbd></kbd></li>
</ul>
<p>
So now the above DOM Selector expression:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:include="mytemplate :: [//div[@class='content']]">...</div>
]]></script>
<p>
...could be written as:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:include="mytemplate :: [div.content]">...</div>
]]></script>
<h4>Fragment specifications adapted to new DOM Selectors</h4>
<p>
Also, in order to better take advantage of the new selector syntax, the syntax of the fragment inclusion
attributes (like the above <kbd>th:include</kbd>) has been modified to <em>convert every fragment selection
into a DOM selection</em>, so that brackets <kbd>[...]</kbd> are no longer needed (though <em>allowed</em>).
</p>
<p>
So the following, with no brackets, is now equivalent to the bracketed selector seen above:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:include="mytemplate :: div.content">...</div>
]]></script>
<p>
So, summarizing, this:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:replace="mytemplate :: myfrag">...</div>
]]></script>
<p>
Will look for a <kbd>th:fragment="myfrag"</kbd> fragment signature. But would also look for tags with name <kbd>myfrag</kbd>
if they existed (which they don't, in HTML). Note the difference with:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:replace="mytemplate :: .myfrag">...</div>
]]></script>
<p>
...which will actually look for any elements with <kbd>class="myfrag"</kbd>, without caring about <kbd>th:fragment</kbd>
signatures.
</p>
<h2><a name="littok"></a>Literal tokens</h2>
<p>
Thymeleaf 2.1 allows for a little bit of simplification in Standard Expressions (i.e. outside
OGNL or SpringEL variable expressions), thanks to the
introduction of <em>literal tokens</em>.
</p>
<p>
These tokens work exactly the same as literals (<kbd>'...'</kbd>), but they
only allow letters (<kbd>A-Z</kbd> and <kbd>a-z</kbd>), numbers (<kbd>0-9</kbd>), brackets
(<kbd>[</kbd> and <kbd>]</kbd>), dots (<kbd>.</kbd>), hyphens (<kbd>-</kbd>) and underscores
(<kbd>_</kbd>). So no whitespaces, no commas, etc.
</p>
<p>
The nice part? tokens don't need any quotes surrounding them. So we can now do this:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:class="content">...</div>
]]></script>
<p>
...instead of:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:class="'content'">...</div>
]]></script>
<h2><a name="bnlit"></a>Boolean and null tokens</h2>
<p>
Boolean and null tokens can now be used (they are <em>reserved tokens</em>). The following is now valid:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:if="${user.isAdmin()} == false"> ...
]]></script>
<p>
Note the difference with what was allowed in 2.0, when the only way to do this was to specify the
<kbd>false</kbd> token inside the OGNL/SpringEL expression and therefore let these expression engines
evaluate it (not thymeleaf).
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:if="${user.isAdmin() == false}"> ...
]]></script>
<p>
The <kbd>null</kbd> token also works as expected:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:if="${variable.something} == null"> ...
]]></script>
<h2><a name="lsub"></a>Literal substitutions</h2>
<p>
The new literal substitutions in Thymeleaf Standard Expressions allow the easy formatting of strings which
may contain values from variables without the need to append literals with <kbd>'...' + '...'</kbd>.
</p>
<p>
These substitutions must be surrounded by vertical bars (<kbd>|</kbd>), like:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<span th:text="|Welcome to our application, ${user.name}!|">
]]></script>
<p>
Which is actually equivalent to:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<span th:text="'Welcome to our application, ' + ${user.name} + '!'">
]]></script>
<p>
Literal substitutions can be combined with other types of expressions:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<span th:text="${onevar} + ' ' + |${twovar}, ${threevar}|">
]]></script>
<p>
<strong>Note</strong>: Note: only variable expressions are allowed inside <kbd>|...|</kbd> literal
substitutions. No other literals (<kbd>'...'</kbd>), boolean/numeric tokens, conditional expressions etc.
are.
</p>
<h2><a name="pru"></a>Protocol-relative URLs</h2>
<p>
Thymeleaf 2.1 allows now protocol-relative URLs, like:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<script th:src="@{//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js}"></script>
]]></script>
<h2><a name="plcom"></a>Parser-level comment blocks</h2>
<p>
Parser-level comment blocks are code that will be simply removed from the template when
thymeleaf parses it. They should look like this:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<!--/* This code will be removed at thymeleaf parsing time! */-->
]]></script>
<p>
Thymeleaf will remove absolutely everything between <kbd><!--/* and */--></kbd>, so
these comment blocks can be used not only for template comments that shouldn't appear in the final result,
but also for displaying code when a template is statically open, knowing that it will be removed when thymeleaf processes it:
</p>
<script type="syntaxhighlighter" class="brush:html"><![CDATA[
<!--/*-->
<div>
you can see me only before thymeleaf processes me!
</div>
<!--*/-->
]]></script>
<p>
This might come very handy for prototyping tables with a lot of <kbd><tr></kbd>'s, for example:
</p>
<script type="syntaxhighlighter" class="brush:html"><![CDATA[
<table>
<tr th:each="x : ${xs}">
...
</tr>
<!--/*-->
<tr>
...
</tr>
<tr>
...
</tr>
<!--*/-->
</table>
]]></script>
<p>
Note that this feature is <em>dialect-independent</em>. So it will be available for us even if we don't
use the Standard Dialects.
</p>
<h2><a name="pocb"></a>Prototype-only comment blocks</h2>
<p>
As an evolution of parser-level comment blocks, Thymeleaf 2.1 allows the definition of
special comment blocks marked to be comments when the template is open statically (i.e. as a <em>prototype</em>),
but <em>considered normal markup</em> by thymeleaf when executing the template.
</p>
<script type="syntaxhighlighter" class="brush:html"><![CDATA[
<span>hello!</span>
<!--/*/
<div th:text="${...}">
...
</div>
/*/-->
<span>goodbye!</span>
]]></script>
<p>
Thymeleaf's parsing system will simply remove the <kbd><!--/*/</kbd> and <kbd>/*/--></kbd> markers, but
not its contents, which will be left therefore <em>uncommented</em>. So when executing the template,
thymeleaf will actually see this:
</p>
<script type="syntaxhighlighter" class="brush:html"><![CDATA[
<span>hello!</span>
<div th:text="${...}">
...
</div>
<span>goodbye!</span>
]]></script>
<p>
As with parser-level comment blocks, note that this feature is also <em>dialect-independent</em>.
</p>
<h2><a name="remove"></a>Improved <kbd>th:remove</kbd> attribute</h2>
<p>
The <kbd>th:remove</kbd> attribute can take now any Thymeleaf Standard Expression, as long as it returns
one of the following String values:
</p>
<ul>
<li><kbd>all</kbd></li>
<li><kbd>tag</kbd></li>
<li><kbd>body</kbd></li>
<li><kbd>all-but-first</kbd></li>
<li><kbd>none</kbd></li>
</ul>
<p>
This means removals could now be conditional, like:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<a href="/something" th:remove="${condition}? tag : none">Link text not to be removed</a>
]]></script>
<p>
Also note that <kbd>th:remove</kbd> could consider <kbd>null</kbd> a synonym to <kbd>none</kbd>, so that the
following works exactly as the example above:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<a href="/something" th:remove="${condition}? tag">Link text not to be removed</a>
]]></script>
<p>
If <kbd>${condition}</kbd> is false, null will be returned, and thus no removal will be performed.
</p>
<h2><a name="bloc"></a>Synthetic <kbd>th:block</kbd> tag</h2>
<p>
Thymeleaf 2.1 adds the first <em>element processor</em> to the Standard Dialects (until now, all processors
were <em>attribute-based</em>): <kbd>th:block</kbd>
</p>
<p>
<kbd>th:block</kbd> is a mere attribute container that allows template developers to specify whichever
attributes they want, executes them, and then simply dissapears without a trace. So it could be useful, for
example, when creating iterated tables that require more than one <kbd><tr></kbd> for each element:
</p>
<script type="syntaxhighlighter" class="brush:html"><![CDATA[
<table>
<th:block th:each="user : ${users}">
<tr>
<td th:text="${user.login}">...</td>
<td th:text="${user.name}">...</td>
</tr>
<tr>
<td colspan="2" th:text="${user.address}">...</td>
</tr>
</th:block>
</table>
]]></script>
<p>
And especially useful when used in combination with <em>prototype-only comment blocks</em>:
</p>
<script type="syntaxhighlighter" class="brush:html"><![CDATA[
<table>
<!--/*/ <th:block th:each="user : ${users}"> /*/-->
<tr>
<td th:text="${user.login}">...</td>
<td th:text="${user.name}">...</td>
</tr>
<tr>
<td colspan="2" th:text="${user.address}">...</td>
</tr>
<!--/*/ </th:block> /*/-->
</table>
]]></script>
<p>
Note how this solution allows templates to be valid HTML (no need to add forbidden <kbd><div></kbd>
blocks inside <kbd><table></kbd>), and still work OK when open statically in browsers as prototypes!
</p>
<h2><a name="data"></a>Support for HTML5-friendly attribute and element names</h2>
<p>
Thymeleaf 2.1 adds a completely new syntax we can use to apply processors to our templates, more
<em>HTML5-friendly</em>.
</p>
<script type="syntaxhighlighter" class="brush:html"><![CDATA[
<table>
<tr data-th-each="user : ${users}">
<td data-th-text="${user.login}">...</td>
<td data-th-text="${user.name}">...</td>
</tr>
</table>
]]></script>
<p>
The <kbd>data-{prefix}-{name}</kbd> syntax is the standard way to write <em>custom attributes</em> in
HTML5, without requiring developers to use any namespaced names like <kbd>th:*</kbd>. Thymeleaf 2.1 makes
this syntax automatically available to all our dialects (not only the Standard ones).
</p>
<p>
There is also a new syntax to specify custom tags: <kbd>{prefix}-{name}</kbd>, which follows the
<em>W3C Custom Elements</em> specification (a part of the larger <em>W3C Web Components</em> spec). We
can use this, for example, for the new <kbd>th:block</kbd> element (or also <kbd>th-block</kbd>):
</p>
<script type="syntaxhighlighter" class="brush:html"><![CDATA[
<!-- ======================================================= -->
<!-- Fully HTML5-valid, both prototype and working template! -->
<!-- ======================================================= -->
<table>
<!--/*/ <th-block data-th-each="user : ${users}"> /*/-->
<tr>
<td data-th-text="${user.login}">...</td>
<td data-th-text="${user.name}">...</td>
</tr>
<tr>
<td colspan="2" data-th-text="${user.address}">...</td>
</tr>
<!--/*/ </th-block> /*/-->
</table>
]]></script>
<p>
<strong>Important</strong>: this new syntax is an <strong>addition</strong> to the namespaced <kbd>th:*</kbd>
one, it does not replace it. There is no intention at all to deprecate the namespaced syntax in the future.
</p>
<h2><a name="assr"></a>New <kbd>th:assert</kbd> for in-template assertions</h2>
<p>
A new <em>attribute processor</em> is now available: <kbd>th:assert</kbd>. This attribute can specify
a comma-separated list of expressions which should be evaluated and produce <kbd>true</kbd> for every
evaluation, raising an exception if not.
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:assert="${onevar},(${twovar} != 43)">...</div>
]]></script>
<p>
This comes in handy for validating parameters at a fragment signature:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<header th:fragment="contentheader(title)" th:assert="${!#strings.isEmpty(title)}">...</header>
]]></script>
<h2><a name="repl"></a>New <kbd>th:replace</kbd> as a synonym of <kbd>th:substituteby</kbd></h2>
<p>
For semantic reasons, a new <kbd>th:replace</kbd> has been introduced as a full synonym of
<kbd>th:substituteby</kbd> (in fact, it was <em>sneakily</em> added in 2.0.18):
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:replace="mytemplate :: .myfrag">...</div>
]]></script>
<p>
Template developers are now recommended to use <kbd>th:replace</kbd> instead of <kbd>th:substituteby</kbd>,
as the latter will probably be deprecated (not <em>removed</em>) in thymeleaf 3.0.
</p>
<h2><a name="with"></a>Reuse variables in <kbd>th:with</kbd></h2>
<p>
As a minor optimization, the <kbd>th:with</kbd> attribute now allows <em>reusing</em> variables defined
in the same attribute:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:with="company=${user.company + ' Co.'},account=${accounts[company]}">...</div>
]]></script>
<br /><br /><br />
<h1><a name="spring"></a>New Features in Spring Integration</h1>
<h2><a name="spbean"></a>More integrated acccess to beans from expressions</h2>
<p>
Thymeleaf now allows us to access beans registered in our Spring application context in the standard
way defined by Spring EL, which is using the syntax <kbd>@beanName</kbd>:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:text="${@authService.getUserName()}">...</div>
]]></script>
<p>
Until now, we could access beans with the thymeleaf-specific
syntax <kbd>beans.beanName</kbd>:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<div th:text="${beans.authService.getUserName()}">...</div>
]]></script>
<p>
Note that this latter syntax is now considered deprecated in favour of the standard Spring EL
one (<kbd>@beanName</kbd>).
</p>
<h2><a name="spconv"></a>Integration of Spring type conversion infrastructure</h2>
<p>
Spring 3 introduced a type conversion system more general than <i>Property Editors</i>: the
<i>Spring Type Conversion System</i> (see
<a href="http://docs.spring.io/spring/docs/3.2.x/spring-framework-reference/html/validation.html#core-convert"
target="_blank">[docs.spring.io]</a>). This system is mainly based on <i>Converters</i>
(X-to-Y one-way conversion) and <i>Formatters</i> (X-to-String two-way conversion), easily implemented
by means of their corresponding interfaces, and registered at a <i>conversion service</i> in the
application context.
</p>
<p>
Thymeleaf now seamlessly integrates with our <i>conversion service</i> thanks to the introduction of
double-bracket expressions, which apply conversion on their result:
</p>
<script type="syntaxhighlighter" class="brush:html;gutter:false"><![CDATA[
<p th:text="${{val}}">...</p>
]]></script>
<p>
So we can now have a formatter like this:
</p>
<script type="syntaxhighlighter" class="brush:java"><![CDATA[
public class CalendarFormatter implements Formatter<Calendar> {
private static final SimpleDateFormat SDF = new SimpleDateFormat("yyyy-MM-dd");
public CalendarFormatter() {
super();
}
public Calendar parse(String text, Locale locale) throws ParseException {
synchronized (SDF) {
final Date date = SDF.parse(text);
final Calendar cal = Calendar.getInstance();
cal.setTimeInMillis(date.getTime());
return cal;
}
}
public String print(Calendar object, Locale locale) {
synchronized (SDF) {
return SDF.format(object.getTime());
}
}
}
]]></script>
<p>
Registered in our application context like this:
</p>
<script type="syntaxhighlighter" class="brush:xml"><![CDATA[
<mvc:annotation-driven conversion-service="conversionService"/>
<bean id="conversionService"
class="org.springframework.format.support.FormattingConversionServiceFactoryBean">
<property name="formatters">
<set>
<bean class="mycompany.myapp.CalendarFormatter"/>
</set>
</property>
</bean>
]]></script>
<p>
Thymeleaf will allow us to use our formatter whenever we need it. So given a
<kbd>Calendar</kbd> variable in context with name <kbd>onedate</kbd>, the following:
</p>
<script type="syntaxhighlighter" class="brush:html"><![CDATA[
<p th:text="${{onedate}}">...</p>
<p th:text="|The date is ${{onedate}}|">...</p>
]]></script>
<p>
Results in:
</p>
<script type="syntaxhighlighter" class="brush:html"><![CDATA[
<p>1492-10-12</p>
<p>The date is 1492-10-12</p>
]]></script>
<h4>Conversion in Spring forms</h4>
<p>
Besides, whenever the converted (double-bracketed) expression refers to a Spring-bound object
(e.g. a form-backing bean) thymeleaf will not only apply the conversion service but also the
property editors and also any formatting annotations. So given:
</p>
<script type="syntaxhighlighter" class="brush:xml"><![CDATA[
<form th:object="${obj}">
<p>Date: <span th:text="*{{date}}">somedate</span></p>
</form>
]]></script>
<p>
If that date field in <kbd>${obj}</kbd> has an annotation like:
</p>
<script type="syntaxhighlighter" class="brush:java"><![CDATA[
@DateTimeFormat(pattern = "yyyy-MM-dd")
private Date date;
]]></script>
<p>
The result will be:
</p>
<script type="syntaxhighlighter" class="brush:xml"><![CDATA[
<form>
<p>Date: <span>1492-10-12</span></p>
</form>
]]></script>
<h4>The <kbd>#conversions</kbd> utility object</h4>
<p>
Besides this double-bracket syntax, a new expression utility object has been added,
allowing the manual execution of the conversion service whenever needed:
</p>
<script type="syntaxhighlighter" class="brush:xml"><![CDATA[
<p th:text="${'Val: ' + #conversions.convert(val,'String')}">...</p>
]]></script>
<p>
Syntax for this utility object:
</p>
<ul>
<li><kbd>#conversions.convert(Object,Class)</kbd>: converts the object to the specified class.</li>
<li><kbd>#conversions.convert(Object,String)</kbd>: same as above, but specifying the target class
as a String (note the <kbd>java.lang.</kbd> package can be ommitted).</li>
</ul>
<h2><a name="spres"></a>Spring-resource based template resolver</h2>
<p>
Thymeleaf now includes a new <kbd>ITemplateResolver</kbd> implementation, besides the standard ones. This
new implementation is called
<kbd>org.thymeleaf.spring3.templateresolver.SpringResourceTemplateResolver</kbd>. It can be specified
at the application context like:
</p>
<script type="syntaxhighlighter" class="brush:xml"><![CDATA[
...
<bean id="templateResolver"
class="org.thymeleaf.spring3.templateresolver.SpringResourceTemplateResolver">
<property name="templateMode" value="HTML5" />
<property name="cacheable" value="true" />
</bean>
<bean id="templateEngine"
class="org.thymeleaf.spring3.SpringTemplateEngine">
<property name="templateResolver" ref="templateResolver" />
</bean>
...
]]></script>
<p>
This new implementation delegates on Spring's own resource resolution mechanism
(<kbd>ApplicationContext.getResource(resourceName)</kbd>), so templates can be now selected
in the same ways Spring itself allows to specify resources, like: