log4j | log4j源码导读 - 1
kandi X-RAY | log4j Summary
kandi X-RAY | log4j Summary
1.在AsyncAppender的实现中,即异步appender的实现中,就是异步的调用Appender中的doAppend()方法,如果现在大部分都会使用blockingqueue 来实现,但是log4j的实现远早于blockingqueue出来的版本,而且log4j2也使用了更高级的disruptor实现,在第一版的实现,log4j实现了一个 非常标准的生产者消费者队列,而且结合了缓冲区进行使用,同时,考虑到了并发的问题,做了许多的补偿处理,如异步线程异常时则使用同步处理, 分派线程被打断时尽量不损失日志事件,美中不足的是虽然还有一些bug,但是设计的我个人觉得是不错的。. 5.我觉得一个框架是否称的上一个好框架,最重要的除了使用的便利、还有一点就是框架的拓展性,我看过的设计的最好的拓展性框架就是spring的设 计,拓展的实现充满在整个框架中;log4j可以让用户便捷的通过配置文件,轻松的决定日志的输出、格式等方式,在便捷方面可以说是设计的很好了, 但拓展我觉得也不应该被忽略,log4j也设计出了许多拓展的实现,虽然达不到spring那样的严谨,比如日志内容的解析、throwable的渲染、Filter 的设计、appender的设计、layout的设计、父子logger之间的解耦、我觉得在这上面还是设计的挺严谨的。. 说完了优点接下来就是缺点了,其实缺点也非常明显,就是性能,log4j的日志打印是通过synchronized来完成的,其中synchronized锁的是父logger ,大部分的logger,的父logger都是rootlogger,那么可以说,log4j的日志打印,实际上是串行打印的,如果使用了多层级的父子logger关系的 时候,就会出现比较多的线程安全问题,比如PatternLayout中的乱序问题、RollFileAppender的多线程操作同一个文件的问题、虽然log4j通过 补偿措施,让当发生这些情况的时候,程序都能有序的进行,但是不知道在结合业务之后会有什么样的不确定性,(虽然log4j2已经全部改良了, 但这里还是要简单描述一下).
Support
Quality
Security
License
Reuse
Top functions reviewed by kandi - BETA
- Creates the tool bar .
- Parse the configuration element .
- Creates a pattern converter .
- Create an abbreviation from a string .
- Parse an appender name .
- Converts String to Level
- Format an element .
- Set the attribute value .
- Find millisecond start .
- Rollover the file .
log4j Key Features
log4j Examples and Code Snippets
Community Discussions
Trending Discussions on Logging
QUESTION
It is difficult to put what I need in a sentence but the code below pretty much explains it:
I have my logging class in a separate file (log_file) as below, and a logger object defined there:
...ANSWER
Answered 2022-Mar-31 at 21:12Yes, you can achieve what you want, actually is well documented under: https://docs.python.org/3/howto/logging.html
There is a parameter where you can provide a dictionary with additional values to your log format.
Below you can find the snippet which does the job:
QUESTION
MySql 5.5 has a few logging option, among which the "Binary Logfile" with Binlog options which I do not want to use and the "query log file" which I want to use.
However, 1 program using 1 table in that database is filling this logfile with 50+Mb per day, so I would like that table to be excluded from this log.
Is that possible, or is the only way to install another MySql version and then to move this 1 table?
Thanks, Alex
...ANSWER
Answered 2022-Mar-29 at 20:14There are options for filtering the binlog by table, but not the query logs.
There are no options for filtering the general query log. It is either enabled for all queries, or else it's disabled.
There are options for filtering the slow query log, but not by table. For example, to log only queries that take longer than N seconds, or queries that don't use an index. Percona Server adds some options to filter the slow query log based on sampling.
You can use a session variable to disable either slow query or general query logging for queries run in a given session. This is a dynamic setting, so you can change it at will. But you would need to change your client code to do this every time you query that specific table.
Another option is to implement log rotation for the slow query log, so it never grows too large. See https://www.percona.com/blog/2013/04/18/rotating-mysql-slow-logs-safely/
QUESTION
I have a kubernetes cluster that's running datadog and some microservices. Each microservice makes healthchecks every 5 seconds to make sure the service is up and running. I want to exclude these healthcheck logs from being ingested into Datadog.
I think I need to use log_processing_rules
and I've tried that but the healthcheck logs are still making it into the logs section of Datadog. My current Deployment looks like this:
ANSWER
Answered 2022-Jan-12 at 20:28I think the problem is that you're defining multiple patterns; the docs state, If you want to match one or more patterns you must define them in a single expression.
Try somtething like this and see what happens:
QUESTION
Suppose, the following is my Multivariable Linear Regression source code in Python:
...ANSWER
Answered 2022-Feb-04 at 07:28Just use the tf.keras.callbacks.CSVLogger
and any regression metric you want to log during training:
QUESTION
I'm trying to implement the an Microsoft.Extensions.Logging.ILogger (copied below for brevity) on a F# Record
...ANSWER
Answered 2022-Jan-28 at 03:34The ILogger
interface requires that you can log objects of any type, but you're trying to log only those of type 'TState
.
Take the signature of BeginScope
:
QUESTION
I have a logger
function from logging
package that after I call it, I can send the message through logging level
.
I would like to send this message also to another function, which is a Telegram function called SendTelegramMsg()
.
How can I get the message after I call the funcion setup_logger
send a message through logger.info("Start")
for example, and then send this exatcly same message to SendTelegramMsg()
function which is inside setup_logger
function?
My currently setup_logger
function:
ANSWER
Answered 2022-Jan-06 at 15:59Picking up the idea suggested by @gold_cy: You implement a custom logging.Handler
. Some hints for that:
- for the handler to be able to send message via a bot, you may want to pass the bot to the handlers
__init__
so that you have it available later emit
must be implemented by you. Here you'll want to callformat
which gives you a formatted version of the log record. You can then use that message to send it via the bot- Maybe having a look at the implementation of
StreamHandler
andFileHandler
is helpful as well
QUESTION
I am using the built in Python "logging" module for my script. When I turn verbosity to "info" it seems like my "debug" messages are significantly slowing down my script.
Some of my "debug" messages print large dictionaries and I'm guessing Python is expanding the text before realizing "debug" messages are disabled. Example:
...ANSWER
Answered 2022-Jan-14 at 22:54Check if the current level is good enough:
QUESTION
Running Xcode 13 I see the following log when launching my iOS app in the Simulator:
Writing analzed variants.
Note that this is, hopefully, a misspelling of the log:
Writing analyzed variants.
What is causing this log noise? Is something in my code triggering it?
How can I hide this "Writing analzed variants." Xcode log?
...ANSWER
Answered 2022-Jan-13 at 17:02According to Quinn “The Eskimo!” at Apple Developer Technical Support, this message is Xcode log noise and can be ignored.
An Apple bug report should be filed to help flag and silence the log.
It’s important to keep an eye on log messages and fix any obvious problems they call out. However, if you see a log message that’s not obviously your fault, it could just be log noise.
There are two criteria you should apply here:
- Is the log message associated with a specific failure? That is, when you see the log message, do you also see other problems?
- Is the log message written in terms you understand? That is, does it reference APIs or data that you’re using?
If the answer to both of these questions is “No”, it’s reasonable to conclude that the log message is just noise and you can ignore it. If you find it to be particularly irksome, file a bug report requesting that it be silenced.
QUESTION
I have implemented a POC and have used slf4j for logging. The zero day vulnerability issue in log4j, did that also impact slf4j logs?
...ANSWER
Answered 2022-Jan-03 at 22:16It depends. Slf4j is just an api, that can be using behind any of its implementions, being log4j just one. Check which one is using on the back, and if this is log4j and between versions 2.0.0 and 2.15.0 (2.15.0 is the one with the fix, versions 1.x are not affected) you should update it (if it is exposed to users directly or indirectly)
QUESTION
I am building a Rust app and I am using Simple Logger to log the init of my app. My main.rs
looks like this:
ANSWER
Answered 2022-Jan-10 at 11:25the comment suggestion from Benjamin Brootz worked. So here's the solution:
Community Discussions, Code Snippets contain sources that include Stack Exchange Network
Vulnerabilities
No vulnerabilities reported
Install log4j
You can use log4j like any standard Java library. Please include the the jar files in your classpath. You can also use any IDE and you can run and debug the log4j component as you would do with any other Java program. Best practice is to use a build tool that supports dependency management such as Maven or Gradle. For Maven installation, please refer maven.apache.org. For Gradle installation, please refer gradle.org .
Support
Reuse Trending Solutions
Find, review, and download reusable Libraries, Code Snippets, Cloud APIs from over 650 million Knowledge Items
Find more librariesStay Updated
Subscribe to our newsletter for trending solutions and developer bootcamps
Share this Page