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any registered observers.</p><p>The observer feature is opt-in and is configured for each realm. In the
<code>StrolchConfiguration.xml</code> file enable observers by adding the
<code>enableObserverUpdates</code> property per realm:</p><divclass=highlight><prestyle=color:#f8f8f2;background-color:#272822;-moz-tab-size:4;-o-tab-size:4;tab-size:4><codeclass=language-xmldata-lang=xml><spanstyle=color:#f92672><StrolchConfiguration></span>
</code></pre></div><p>Registering for updates is done by registering an Observer on the
ObserverHandler of the realm itself:</p><divclass=highlight><prestyle=color:#f8f8f2;background-color:#272822;-moz-tab-size:4;-o-tab-size:4;tab-size:4><codeclass=language-javadata-lang=java>ObserverHandler observerHandler <spanstyle=color:#f92672>=</span> container<spanstyle=color:#f92672>.</span><spanstyle=color:#a6e22e>getRealm</span><spanstyle=color:#f92672>(</span>StrolchConstants<spanstyle=color:#f92672>.</span><spanstyle=color:#a6e22e>DEFAULT_REALM</span><spanstyle=color:#f92672>).</span><spanstyle=color:#a6e22e>getObserverHandler</span><spanstyle=color:#f92672>();</span>
logger<spanstyle=color:#f92672>.</span><spanstyle=color:#a6e22e>info</span><spanstyle=color:#f92672>(</span>elements<spanstyle=color:#f92672>.</span><spanstyle=color:#a6e22e>size</span><spanstyle=color:#f92672>()</span><spanstyle=color:#f92672>+</span><spanstyle=color:#e6db74>" resources were updated!"</span><spanstyle=color:#f92672>);</span>
logger<spanstyle=color:#f92672>.</span><spanstyle=color:#a6e22e>info</span><spanstyle=color:#f92672>(</span>elements<spanstyle=color:#f92672>.</span><spanstyle=color:#a6e22e>size</span><spanstyle=color:#f92672>()</span><spanstyle=color:#f92672>+</span><spanstyle=color:#e6db74>" resources were removed!"</span><spanstyle=color:#f92672>);</span>
logger<spanstyle=color:#f92672>.</span><spanstyle=color:#a6e22e>info</span><spanstyle=color:#f92672>(</span>elements<spanstyle=color:#f92672>.</span><spanstyle=color:#a6e22e>size</span><spanstyle=color:#f92672>()</span><spanstyle=color:#f92672>+</span><spanstyle=color:#e6db74>" resources were added!"</span><spanstyle=color:#f92672>);</span>