How to inform a Java Program that the data of a DB have changed
<p>I created a Java program that every 30 Minutes, reads information from a database, keeping them in a structure <a href="https://docs.oracle.com/javase/7/docs/api/java/util/Vector.html" rel="nofollow"><code>Vector&lt;Vector&lt;Object&gt;&gt;</code></a>.
To do this use <a href="https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/ScheduledExecutorService.html" rel="nofollow"><code>ScheduledExecutorService</code></a>.</p>

<p>I created a second Java program that allows you to Add/Modify/Delete items from the database. How do I inform the first program that some changes took place in the database and then re-read the new information without waiting the 30 minutes?</p>

<p>The first program is always active, while the second is executed only in the case where it is necessary to make a change.</p>