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copied!<p>These 2 sentences are red flags for me :</p> <blockquote> <p>When we start the application we pull all the information from the database and transform it into objects to use in our application (using java sql statemens). In the application we edit some of these objects and then when we exit the application we save or update information in the database using Hibernate.</p> </blockquote> <p>Is there a requirements reason that you are loading all the information from the database into memory at startup, or why you're waiting until shutdown to save changes back in the database? </p> <p>If not, I'd suggest a design change. If you've already got Hibernate mappings for the tables in the DB, I'd use Hibernate for both all of your CRUD (create, read, update, delete) operations. And, I'd only load the data that each page in your app needs, as it needs it.</p> <p>If you can't make that kind of design change at this point, I think you've got to look closely at how you're managing the database connections. Are you using connection pools? Are you opening up multiple connections? Forgetting to release them?</p> <p>Something else to look at. How are you using Hibernate to save the entities to the db? Are you doing a getHibernateTemplate().get on each one and then doing an entity.save or entity.update on each one? If so, that means you are also causing Hibernate to run a select query for each database object before it does a save or update. So, essentially, you'd be loading each database object twice (once at the beginning of the program, once before saving). To see if that's what's happening, you can turn on the <a href="http://www.mkyong.com/hibernate/hibernate-display-generated-sql-to-console-show_sql-format_sql-and-use_sql_comments/" rel="nofollow noreferrer">show_sql property</a> or use <a href="http://www.mkyong.com/hibernate/how-to-display-hibernate-sql-parameter-values-solution/" rel="nofollow noreferrer">P6Spy</a> to see exactly what queries Hibernate is running.</p>

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