Top 5 Java Performance Problems and How to Solve Them

No matter how experienced of a developer you are, you’re going to run into problems from time to time. In fact, learning to overcome these problems is one of the key components of an experienced, quality developer. Even if you’re not personally experiencing a problem, taking the time to review some of the most common performance issues is a great way to increase the performance of your own app in the process.

It’s essential to make sure your Java app is running at its highest level. We live in a competitive world of app development. Nearly one in four users abandon mobile apps in particular after only one use. That’s reason enough to take this list seriously. Your app deserves to run perfectly to attract users who come back again and again. Here are the top 5 Java performance problems and how to solve them for good.

1. Caching Problems

Caching is necessary, but sometimes it doesn’t work properly. When you cache an application, it loads faster since the user’s device doesn’t need to reach the server every time a resource is needed. Failing to use caching will slow down the app considerable, but the cache also needs to be properly configured to avoid running out of memory.

You might also experience a problem with distributed caching which requires synchronization to reach multiple servers. How do you troubleshoot the problem? First, you’ll need to check out the performance of the database. From there, determine the cache size with hit ratio and miss ratio.

2. Not Having a Performance Test

Performance tests are necessary to check how well your app is working for users. If you don’t have a performance test, it’s time to make one. After you deploy any improvements, you should define a performance test suite which will test the entire application for any problems you might be overlooking.

Testing is always a good idea. Any time you’re making changes, you run the risk of doing more harm than good for your users. Creating a performance test is a must for any Java developer.

3. Using BigInteger or BigDecimal

BigInteger and BigDecimal are popular in Java, but they come at a cost. If you’re noticing performance problems, these might be to blame. Why’s this? Both use much more memory than a long or double, so it’ll weigh down your application.

Instead, think long and hard about whether you actually need these precision data types. Otherwise, switch them out for something that won’t slow down your application.

4. Using Debug Messages Too Early

If you notice an error in your code slowing you down, don’t jump right into your debug messages. If you do, you might make a String with your log message that’ll only be ignored. It’s always better to start by checking your current log level first.

If you write a debug message without knowing if your logging framework will even use that message, you’re wasting your time. Check your log level before you create any debug message. You’ll be glad you did. (Source: https://www.loggly.com/blog/java-code-coverage-with-cobertura-and-jenkins)

5. Using the String.replace Method

A lot of developers jump right into using the String.replace method for replacing operations. However, this isn’t the most efficient option and you’ll end up spending more time on the process than you would if you used Apache Commons Lang’s StringUtilis.replace method. This method is much better, and it even outperforms Java 8’s String.replace method.

How do you do this? You’ll need to start with a Maven dependency for the Apache’s Commons Lang project. From there, replace the calls of the String.replace method with StringUtilis.replace method. You’re good to go after that.

Conclusion

It doesn’t always take a lot of effort to solve performance problems in your Java application. In this day and age, you can’t afford a slow, poorly performing app. As a developer, it’s up to you to analyze the state of your current app to find what’s best for your situation.

Start with these tips above to brush up on the status of your app. Making the necessary changes might take a bit of time, but it’s well worth the results.