title: JPA find() method with vendor-specific properties
body: <p>I am new to JPA and I have started using it recently. I have a doubt with the following method which was introduced in JPA 2.0 - </p>
  
  <pre><code> public &lt;T&gt; T find(Class&lt;T&gt; entityClass, Object primaryKey, 
                    Map&lt;String, Object&gt; properties); 
  </code></pre>
  
  <p>The documentation says, <strong>Find by primary key, using the vendor specified properties.</strong> </p>
  
  <p>But I am unable to understand what are those vendor specific properties and under what situation this overloaded find() method should be used.</p>
  
  <p>Can any one explain this to me with a suitable example. Thanks in advance.</p>