what should I use to track details of mutable objects in java
<p>I want to store credit history information about people objects in a simulation. </p>

<p>I wanted to use <code>HashMap&lt;Person, CreditHistory&gt;</code>, but the java API says I should be wary about using HashMaps to track mutable objects (like credit history, in my program). </p>

<p><a href="http://docs.oracle.com/javase/1.5.0/docs/api/java/util/HashMap.html" rel="nofollow">http://docs.oracle.com/javase/1.5.0/docs/api/java/util/HashMap.html</a></p>

<p>Is there a better structure for this? </p>
