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     <a class="edit-on-gh" href="https://github.com/apache/struts-site/edit/master/source/core-developers/formatting-dates-and-numbers.md" title="Edit this page on GitHub">Edit on GitHub</a>
     <h1 id="formatting-dates-and-numbers">Formatting Dates and Numbers</h1>

 <h2 id="defining-formats">Defining Formats</h2>

 <p>Struts2 supports localization (l10n) aware formatting of dates, times and numbers very easily, utilizing Java’s
 built-in date formatting features.</p>

 <p>As seen in the <a href="localization.html">Localization</a> chapter, it is quite easy to define hierarchical resource bundles
 with Struts2, giving the developer the opportunity to define locale dependent message formats. This is the entry point
 to define the needed date, time and number formats. Your default properties could contain the following generic formats:</p>

 <div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>format.time = {0,time}
 format.number = {0,number,#0.0##}
 format.percent = {0,number,##0.00'%'}
 format.money = {0,number,\u00A4##0.00}
 </code></pre></div></div>

 <p>An appropriate en_US format definition extension could look like this:</p>

 <div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>format.date = {0,date,MM/dd/yy}
 </code></pre></div></div>

 <p>In parallel, you could add the following to your de_DE bundle:</p>

 <div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>format.date = {0,date,dd.MM.yyyy}
 </code></pre></div></div>

 <p>Read more on how to define message formats in Sun’s Java API docs for <a href="http://java.sun.com/j2se/1.5.0/docs/api/java/text/MessageFormat.html">MessageFormat</a>.</p>

 <p>Now that we have our formats set up, it is quite easy to use them in our views.</p>

 <h2 id="formatting-output-using-the-stext-tag">Formatting output using the s:text tag</h2>

 <p>Given you had a Float value myMoneyValue, accessible through the getter getMyMoneyValue in your action, the following
 code would print out localized representation of the value as a currency amount, using the format.money message
 format defined above with a <code class="highlighter-rouge">s:text</code> tag:</p>

 <pre><code class="language-jsp">&lt;s:text name="format.money"&gt;
     &lt;s:param name="value" value="myMoneyValue"/&gt;
 &lt;/s:text&gt;
 </code></pre>

 <p>The (first) parameter defines the value which is to replace the ‘0’ placeholder in the defined message format.</p>

 <p>Another example, formatting a date value:</p>

 <pre><code class="language-jsp">&lt;s:text name="format.date"&gt;&lt;s:param value="dueDate"/&gt;&lt;/s:text&gt;
 </code></pre>

 <blockquote>
   <p>While the <code class="highlighter-rouge">s:text</code> tag is very useful to format numbers, date formatting has become a lot easier thanks
 to the <code class="highlighter-rouge">s:date</code> tag.</p>
 </blockquote>

 <h2 id="localizing-form-data-with-gettext">Localizing form data with getText</h2>

 <p>Placing a textfield in a form like this</p>

 <pre><code class="language-jsp">&lt;s:textfield key="orderItem.price" /&gt;
 </code></pre>

 <p>to input a number, one might have noticed that the number is always shown in the Java default number format. Not only
 that this is not “nice”, if you are in a non-en locale, it will also cause trouble when submitting the form since type
 conversion is locale aware. The solution is to again use the message formats as defined above, by using the getText
 method of ActionSupport:</p>

 <pre><code class="language-jsp">&lt;s:textfield key="orderItem.price" value="%{getText('format.number',{orderItem.price})}" /&gt;
 </code></pre>

 <p>This maps to the method signature <code class="highlighter-rouge">getText( String key, Object[] params )</code> in ActionSupport.</p>

 <h2 id="using-getformatted-with-conversion-support">Using getFormatted() with conversion support</h2>

 <p>A new method getFormatted was added to ActionSupport (which can be implemented in your base action) to support
 formatting and conversion errors with I10N.</p>

 <p>You can place a code like below</p>

 <pre><code class="language-jsp">&lt;s:textfield key="user.born" value="%{getFormatted('format.number','user.born')}" /&gt;
 </code></pre>

 <p>to get support for I10N and also to support conversion errors.</p>

   </section>
 </article>


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	<a href="index.html" title="back to Core Developers Guide"><< back to Core Developers Guide</a>
	<a class="edit-on-gh" href="https://github.com/apache/struts-site/edit/master/source/core-developers/formatting-dates-and-numbers.md" title="Edit this page on GitHub">Edit on GitHub</a>
	<h1 id="formatting-dates-and-numbers">Formatting Dates and Numbers</h1>

	<h2 id="defining-formats">Defining Formats</h2>

	<p>Struts2 supports localization (l10n) aware formatting of dates, times and numbers very easily, utilizing Java’s
	built-in date formatting features.</p>

	<p>As seen in the <a href="localization.html">Localization</a> chapter, it is quite easy to define hierarchical resource bundles
	with Struts2, giving the developer the opportunity to define locale dependent message formats. This is the entry point
	to define the needed date, time and number formats. Your default properties could contain the following generic formats:</p>

	<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>format.time = {0,time}
	format.number = {0,number,#0.0##}
	format.percent = {0,number,##0.00'%'}
	format.money = {0,number,\u00A4##0.00}
	</code></pre></div></div>

	<p>An appropriate en_US format definition extension could look like this:</p>

	<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>format.date = {0,date,MM/dd/yy}
	</code></pre></div></div>

	<p>In parallel, you could add the following to your de_DE bundle:</p>

	<div class="highlighter-rouge"><div class="highlight"><pre class="highlight"><code>format.date = {0,date,dd.MM.yyyy}
	</code></pre></div></div>

	<p>Read more on how to define message formats in Sun’s Java API docs for <a href="http://java.sun.com/j2se/1.5.0/docs/api/java/text/MessageFormat.html">MessageFormat</a>.</p>

	<p>Now that we have our formats set up, it is quite easy to use them in our views.</p>

	<h2 id="formatting-output-using-the-stext-tag">Formatting output using the s:text tag</h2>

	<p>Given you had a Float value myMoneyValue, accessible through the getter getMyMoneyValue in your action, the following
	code would print out localized representation of the value as a currency amount, using the format.money message
	format defined above with a <code class="highlighter-rouge">s:text</code> tag:</p>

	<pre><code class="language-jsp"><s:text name="format.money">
	<s:param name="value" value="myMoneyValue"/>
	</s:text>
	</code></pre>

	<p>The (first) parameter defines the value which is to replace the ‘0’ placeholder in the defined message format.</p>

	<p>Another example, formatting a date value:</p>

	<pre><code class="language-jsp"><s:text name="format.date"><s:param value="dueDate"/></s:text>
	</code></pre>

	<blockquote>
	<p>While the <code class="highlighter-rouge">s:text</code> tag is very useful to format numbers, date formatting has become a lot easier thanks
	to the <code class="highlighter-rouge">s:date</code> tag.</p>
	</blockquote>

	<h2 id="localizing-form-data-with-gettext">Localizing form data with getText</h2>

	<p>Placing a textfield in a form like this</p>

	<pre><code class="language-jsp"><s:textfield key="orderItem.price" />
	</code></pre>

	<p>to input a number, one might have noticed that the number is always shown in the Java default number format. Not only
	that this is not “nice”, if you are in a non-en locale, it will also cause trouble when submitting the form since type
	conversion is locale aware. The solution is to again use the message formats as defined above, by using the getText
	method of ActionSupport:</p>

	<pre><code class="language-jsp"><s:textfield key="orderItem.price" value="%{getText('format.number',{orderItem.price})}" />
	</code></pre>

	<p>This maps to the method signature <code class="highlighter-rouge">getText( String key, Object[] params )</code> in ActionSupport.</p>

	<h2 id="using-getformatted-with-conversion-support">Using getFormatted() with conversion support</h2>

	<p>A new method getFormatted was added to ActionSupport (which can be implemented in your base action) to support
	formatting and conversion errors with I10N.</p>

	<p>You can place a code like below</p>

	<pre><code class="language-jsp"><s:textfield key="user.born" value="%{getFormatted('format.number','user.born')}" />
	</code></pre>

	<p>to get support for I10N and also to support conversion errors.</p>

	</section>
	</article>


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