Java logging is integral to maintaining the performance and health of your applications, as examining Java logs is often the quickest way to discover why your application is experiencing a problem. Java logging best practices can enhance your ability to troubleshoot and resolve problems before they impact your users or organization. In many cases, this means using a Java logging tool capable of automating your processes and providing quicker and more accurate results than manual logging alone.
Java logging depends on the use of at least one Java logging framework. This framework provides the methods, objects, and configurations needed to create and send log messages. There are many Java logging libraries and frameworks available, but the two most commonly used ones are logback and Log4j.
You should consider which framework best suits your needs before selecting a Java logging tool—you want to ensure the solution you choose is compatible with your chosen framework. For most people, Log4j is a good choice because it can be easily configured, it consistently provides good performance, and it has an active development community.
The overall best practice for Java logging is logging as much as possible while allowing for easy access to the relevant information within the logs. Of course, this is easier said than done, which is why there are several best practices you should follow in pursuit of those larger goals. These best practices include the following five tips:
Create and set log severity levels to make your logs easier to read and to make sure you don’t accidentally miss important logs. Though it’s helpful to collect as much information as possible in your logs, it’s also important to avoid losing sight of the logs capable of indicating problems with your application just because they’re not distinguished from less significant logs.
You can create five basic log severity levels: Debug/Verbose, Info, Warning (when something unusual occurs, though it may not impact the users), Error (for problems requiring investigation), and Critical/Fatal (for problems you need to address immediately).
Write your logs knowing you won’t be the only one reading them, and make sure they’re clear and can easily be parsed. This might mean printing two logs: one to be used by computers and one for human readers.
Include metadata in your logs so you’re better able to pinpoint production problems. The more metadata you add, the more helpful your log will be. Incorporating metadata like class, category, method, and thread ID will help you identify the root cause of an error when it occurs.
Do not write overly large logs. When you incorporate unrelated or unnecessary information, you can reduce the value of a log by masking the data you need. You can also create problems with performance or bandwidth when writing your logs to your disk. Though detailed, descriptive logs are great, it’s important to avoid using logs to store unrelated data.
Make sure you’re logging exceptions correctly and aren’t accidentally reporting them multiple times. The best way to do this is to simply allow your log monitoring solution to take care of reporting exceptions for you. An automated tool can even create alerts from specific types of log data to ensure you get more accurate insights into urgent matters.
The success of your Java application depends on collecting logs effectively and being able to extract useful information from them. This data provides you with information about the application’s usability, stability, and performance so you can keep the application running smoothly.
The first step for successful troubleshooting is to gather the log data providing insight into the application in question. If an anomaly or performance issue occurs, you can parse and analyze this data for further insight into the problem. With this information, you can more quickly identify the actual source of the issue and mitigate the problem.
However, parsing and analyzing your log data can be time-consuming. Parsing log data on your own typically involves using command-line utilities (like uniq and grep) capable of combining information from log files and extracting the most pertinent and useful information. However, this kind of manual log analysis can get in the way of effective troubleshooting because it can significantly slow down the process of locating the source of the problem.
This process can be simplified thanks to several tools, from Java log analyzers to tools for parsing and consolidating data. You can choose cloud-based services like SolarWinds® Loggly®, which is designed to take care of log data storage and offers analysis capabilities. These tools simplify the process of querying, sorting, and filtering log events by automatically processing and storing your log data. They let you use simple commands to search and extract the logs you need, eliminating stress and the challenge of having to parse and analyze log data on your own.
If you’re looking for a log management tool, start with SolarWinds Loggly. Loggly simplifies the log parsing and analysis process and provides you with insights to help you better troubleshoot problems. It automatically detects and parses stack traces into individual tokens using its predefined filters and provides point-and-click solutions to help you sort through your logs without having to memorize complex grep commands. The visualization tools in Loggly are also clearer and easier to understand than the text-based output you get with grep.
Loggly indexes your log records, making counts and searches quicker than they would be with grep. For example, Loggly Dynamic Field Explorer™ lets you quickly find logs by exception type. Additionally, it allows you to view a list of exceptions and their frequencies, and you can click on specific exceptions to see all the relevant logs.
Loggly lets you monitor your logs in real time with its live log tail feature. It also comes with a surround search feature, allowing you to investigate critical events.
The information you can gain from Java logs is crucial for maintaining your application performance and keeping your users happy. By collecting sufficient real-time data and ensuring your logs are parsed effectively, you can maximize the impact of your Java logging efforts.
Though it’s possible to integrate these best practices by simply using command-line utilities and other basic tools, the best way to make sure you’re engaging in Java logging best practices is by using an effective log management tool. Start with SolarWinds Loggly as your Java parser, analyzer, and monitor. This tool is designed to help you centralize your Java log files, so you can streamline and simplify your management, search, and analysis.