In Java, why is it best practice to declare a logger static final? Improve this question. Add a comment. Active Oldest Votes. Improve this answer. Community Bot 1 1 1 silver badge.
Tomasz Nurkiewicz Tomasz Nurkiewicz k 66 66 gold badges silver badges bronze badges. Some follow Java naming convention religiously nothing wrong with that , but I prefer easier to write and more pleasant to read log name rather than scattering the code with LOG. Just a matter of dev. Please note that it is no longer always recommended to declare loggers as static and final, see slf4j.
Logger isn't constant. Show 8 more comments. This is how you use slf4j with jcabi-log : import com. An interesting alternative and definitely cleaner. I wonder how this scales compared to individual class loggers.
Write longer Logger.. The first comment in the related blog post indicates the evil side of the static methods : So using private final Logger is the best practice I guess. Andrzej Doyle Andrzej Doyle When would you want to change the value of the field? Jon Skeet Jon Skeet 1. In many-many cases it IS obvious without adding the word final, which it this case becomes a kind of junk.
Dima: Well I'm still grateful that the compiler will still throw an error if I do accidentally try to change the value in these cases Liv Liv 5, 1 1 gold badge 20 20 silver badges 29 29 bronze badges.
To answer that question, you should have asked yourself what "static" and "final" are for. Tim Cooper k 36 36 gold badges silver badges bronze badges. Daniel Leschkowski Daniel Leschkowski 7 7 silver badges 11 11 bronze badges. Sign up to join this community.
The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Why create a Logger object instead of using static logging methods across an application?
Ask Question. Asked 6 years, 3 months ago. Active 3 years, 3 months ago. Viewed 6k times. It creates a Logger object during application load process: in environment.
Optimization needed. Even if Logger. Improve this question. Harsh Gupta Harsh Gupta 1 1 gold badge 5 5 silver badges 9 9 bronze badges. Add a comment. Connect and share knowledge within a single location that is structured and easy to search. Most applications will use one logger per class, where the name of the logger is the same as the name of the class.
With log4net, using one logger per class makes it easy to capture the source of the log message ie. If you don't have one logger per class, but instead have one logger for the entire app, you need to resort to more reflection tricks to know where the log messages are coming from.
Using the second example, the Logger would need to build a stack trace to see who was calling it or your code would always have to pass in the caller. With the logger-per-class style, you still do this, but you can do it once per class instead of once per call and eliminate a serious performance problem.
NLogger has a very useful code snippet to do this. The nlogger snippet will create the following code:. So only few keystrokes and you have logger per class.
It will use namespace and class name as the name of the logger. To set different name to your class logger, you can use this:. In most cases, the name of the class provides a good name for the logger. When scanning the log files, you can see the log message and associate it directly with a line of code. A good example where this is not the best approach, is Hibernate's SQL logs. There is a shared logger named "Hibernate.
SQL" or something like that, where a number of different classes write raw SQL out to a single logger category. From a development standpoint, it's easiest if you don't have to create a logger object each time. On the other hand, if you don't, but rather you create it dynamically using reflection, it'll slow down performance.
To solve this, you can use the following code which creates the logger dynamically asynchronously:. Probably because you want to be able to log methods that are only visible to the class without breaking encapsulation, this also makes it easy to use the class in another application without breaking the logging functionality. If you are using NLOG you can specify the callsite in the config, this will record the class name and method where the logging statement was located.
Disclaimer: I don't know how NLOG collects this information, my guess would be reflection so you may need to consider the performance. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. It is good programming practice to share a single logger object between all of the instances of a particular class and to use the same logger for the duration of the program.
It is a poor logging practice to use multiple loggers rather than logging levels in a single class. Good logging practice dictates the use of a single logger that supports different logging levels for each class.
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