Find out how many database calls you are making and minimize those believe it or not if you see performance in seconds than in most cases culprit is database access code. since connecting todatabase requires connections to be prepared, network round trip and processing on database side, its best to avoid databasecall if you can work with cached value. even if your application has quite dynamic data having a short time cache can save many database round trip which can boost your java applicationperformance by almost 20-50% based on how many calls got reduced.
Java database performance tips 2:
Check whether your database has indexed on columns if you are reading from database.
Java database performance tips 3:
Use PreparedStatement or Stored Procedure for executing query Prepared Statements are much faster than normal Statement object as database can pre-compile them and also cache there query plan.
Java database performance tips 4:
Use Connection Pool for holding Database Connections.