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<h1 id="subset">subset</h1>
<p>Please make sure you have read the <a href="tag-syntax">Tag Syntax</a> document and understand how tag attribute syntax works.</p>
<h2 id="description">Description</h2>
<p>A tag that takes an iterator and outputs a subset of it. It delegates to <code class="highlighter-rouge">org.apache.struts2.util.SubsetIteratorFilter</code>
internally to perform the subset functionality.</p>
<p>Takes an iterator and outputs a subset of it.</p>
<h2 id="attributes">Attributes</h2>
<table width="100%">
<tr>
<td colspan="6"><h4>Dynamic Attributes Allowed:</h4> false</td>
</tr>
<tr>
<td colspan="6">&nbsp;</td>
</tr>
<tr>
<th align="left" valign="top"><h4>Name</h4></th>
<th align="left" valign="top"><h4>Required</h4></th>
<th align="left" valign="top"><h4>Default</h4></th>
<th align="left" valign="top"><h4>Evaluated</h4></th>
<th align="left" valign="top"><h4>Type</h4></th>
<th align="left" valign="top"><h4>Description</h4></th>
</tr>
<tr>
<td align="left" valign="top">count</td>
<td align="left" valign="top">false</td>
<td align="left" valign="top"></td>
<td align="left" valign="top">false</td>
<td align="left" valign="top">Integer</td>
<td align="left" valign="top">Indicate the number of entries to be in the resulting subset iterator</td>
</tr>
<tr>
<td align="left" valign="top">decider</td>
<td align="left" valign="top">false</td>
<td align="left" valign="top"></td>
<td align="left" valign="top">false</td>
<td align="left" valign="top">org.apache.struts2.util.SubsetIteratorFilter.Decider</td>
<td align="left" valign="top">Extension to plug-in a decider to determine if that particular entry is to be included in the resulting subset iterator</td>
</tr>
<tr>
<td align="left" valign="top">source</td>
<td align="left" valign="top">false</td>
<td align="left" valign="top"></td>
<td align="left" valign="top">false</td>
<td align="left" valign="top">String</td>
<td align="left" valign="top">Indicate the source of which the resulting subset iterator is to be derived base on</td>
</tr>
<tr>
<td align="left" valign="top">start</td>
<td align="left" valign="top">false</td>
<td align="left" valign="top"></td>
<td align="left" valign="top">false</td>
<td align="left" valign="top">Integer</td>
<td align="left" valign="top">Indicate the starting index (eg. first entry is 0) of entries in the source to be available as the first entry in the resulting subset iterator</td>
</tr>
<tr>
<td align="left" valign="top">var</td>
<td align="left" valign="top">false</td>
<td align="left" valign="top"></td>
<td align="left" valign="top">false</td>
<td align="left" valign="top">String</td>
<td align="left" valign="top">The name to store the resultant iterator into page context, if such name is supplied</td>
</tr>
</table>
<h2 id="examples">Examples</h2>
<div class="language-java highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="kd">public</span> <span class="kd">class</span> <span class="nc">MySubsetTagAction</span> <span class="kd">extends</span> <span class="n">ActionSupport</span> <span class="o">{</span>
<span class="kd">public</span> <span class="n">String</span> <span class="nf">execute</span><span class="o">()</span> <span class="kd">throws</span> <span class="n">Exception</span> <span class="o">{</span>
<span class="n">l</span> <span class="o">=</span> <span class="k">new</span> <span class="n">ArrayList</span><span class="o">();</span>
<span class="n">l</span><span class="o">.</span><span class="na">add</span><span class="o">(</span><span class="k">new</span> <span class="n">Integer</span><span class="o">(</span><span class="mi">1</span><span class="o">));</span>
<span class="n">l</span><span class="o">.</span><span class="na">add</span><span class="o">(</span><span class="k">new</span> <span class="n">Integer</span><span class="o">(</span><span class="mi">2</span><span class="o">));</span>
<span class="n">l</span><span class="o">.</span><span class="na">add</span><span class="o">(</span><span class="k">new</span> <span class="n">Integer</span><span class="o">(</span><span class="mi">3</span><span class="o">));</span>
<span class="n">l</span><span class="o">.</span><span class="na">add</span><span class="o">(</span><span class="k">new</span> <span class="n">Integer</span><span class="o">(</span><span class="mi">4</span><span class="o">));</span>
<span class="n">l</span><span class="o">.</span><span class="na">add</span><span class="o">(</span><span class="k">new</span> <span class="n">Integer</span><span class="o">(</span><span class="mi">5</span><span class="o">));</span>
<span class="k">return</span> <span class="s">"done"</span><span class="o">;</span>
<span class="o">}</span>
<span class="kd">public</span> <span class="n">Integer</span><span class="o">[]</span> <span class="nf">getMyArray</span><span class="o">()</span> <span class="o">{</span>
<span class="k">return</span> <span class="n">a</span><span class="o">;</span>
<span class="o">}</span>
<span class="kd">public</span> <span class="n">List</span> <span class="nf">getMyList</span><span class="o">()</span> <span class="o">{</span>
<span class="k">return</span> <span class="n">l</span><span class="o">;</span>
<span class="o">}</span>
<span class="kd">public</span> <span class="n">Decider</span> <span class="nf">getMyDecider</span><span class="o">()</span> <span class="o">{</span>
<span class="k">return</span> <span class="k">new</span> <span class="nf">Decider</span><span class="o">()</span> <span class="o">{</span>
<span class="kd">public</span> <span class="kt">boolean</span> <span class="nf">decide</span><span class="o">(</span><span class="n">Object</span> <span class="n">element</span><span class="o">)</span> <span class="kd">throws</span> <span class="n">Exception</span> <span class="o">{</span>
<span class="kt">int</span> <span class="n">i</span> <span class="o">=</span> <span class="o">((</span><span class="n">Integer</span><span class="o">)</span><span class="n">element</span><span class="o">).</span><span class="na">intValue</span><span class="o">();</span>
<span class="k">return</span> <span class="o">(((</span><span class="n">i</span> <span class="o">%</span> <span class="mi">2</span><span class="o">)</span> <span class="o">==</span> <span class="mi">0</span><span class="o">)?</span><span class="kc">true</span><span class="o">:</span><span class="kc">false</span><span class="o">);</span>
<span class="o">}</span>
<span class="o">};</span>
<span class="o">}</span>
<span class="o">}</span>
</code></pre></div></div>
<p><strong>Basic example</strong></p>
<pre><code class="language-jsp">&lt;s:subset source="myList"&gt;
&lt;s:iterator&gt;
&lt;s:property /&gt;
&lt;/s:iterator&gt;
&lt;/s:subset&gt;
</code></pre>
<p><strong>List with count</strong></p>
<div class="language-xml highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="nt">&lt;s:subset</span> <span class="na">source=</span><span class="s">"myList"</span> <span class="na">count=</span><span class="s">"3"</span><span class="nt">&gt;</span>
<span class="nt">&lt;s:iterator&gt;</span>
<span class="nt">&lt;s:property</span> <span class="nt">/&gt;</span>
<span class="nt">&lt;/s:iterator&gt;</span>
<span class="nt">&lt;/s:subset&gt;</span>
</code></pre></div></div>
<p><strong>List with start</strong></p>
<pre><code class="language-jsp">&lt;s:subset source="myList" count="13" start="3"&gt;
&lt;s:iterator&gt;
&lt;s:property /&gt;
&lt;/s:iterator&gt;
&lt;/s:subset&gt;
</code></pre>
<p><strong>List with var</strong></p>
<pre><code class="language-jsp">&lt;s:subset var="mySubset" source="myList" count="13" start="3" /&gt;
&lt;%
Iterator i = (Iterator) pageContext.getAttribute("mySubset");
while(i.hasNext()) {
%&gt;
&lt;%=i.next() %&gt;
&lt;% } %&gt;
</code></pre>
<p><strong>List with Decider</strong></p>
<pre><code class="language-jsp">&lt;s:subset source="myList" decider="myDecider"&gt;
&lt;s:iterator&gt;
&lt;s:property /&gt;
&lt;/s:iterator&gt;
&lt;/s:subset&gt;
</code></pre>
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