log4J2日志未写入文件

Question

I want to store logs in 2 different files. On the one hand, my logs are not written to the files, but the files are created and on the other hand, only "error" and "fatal" -levels are displayed in the console. property file:

name=PropertiesConfig
property.filename = logs
appenders = console, user, system

appender.console.type = Console
appender.console.name = STDOUT
appender.console.layout.type = PatternLayout
appender.console.layout.pattern = [%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %c{1} - %msg%n



appender.user.type = File
appender.user.name = LOGFILE
appender.user.fileName=${filename}/user.log
appender.user.layout.type=PatternLayout
appender.user.layout.pattern=[%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] c{1} - %msg%n
appender.user.MaxFileSize=5120KB
appender.user.MaxBackupIndex=10


appender.system.type = File
appender.system.name = LOGFILE
appender.system.fileName=${filename}/system.log
appender.system.layout.type=PatternLayout
appender.system.layout.pattern=[%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] c{1} - %msg%n
appender.system.MaxFileSize=5120KB
appender.system.MaxBackupIndex=10




Loggers = file
logger.file.name = de.pares.int_plan
logger.file.level = All
logger.file.appenderRefs = file
logger.file.appenderRef.file.ref  = LOGFILE

This is how I create the loggers:

private static Logger userLog = LogManager.getLogger("user");
private static Logger systemLog = LogManager.getLogger("system");

Use theem like this:

userLog.debug("UserLogger: This is a debug message");
userLog.info("UserLogger: This is an info message");
userLog.warn("UserLogger: This is a warn message");
userLog.error("UserLogger: This is an error message");
userLog.fatal("UserLogger: This is a fatal message");

systemLog.debug("SystemLogger: This is a debug message");
systemLog.info("SystemLogger: This is an info message");
systemLog.warn("SystemLogger: This is a warn message");
systemLog.error("SystemLogger: This is an error message");
systemLog.fatal("SystemLogger: This is a fatal message");

what im doing wrong?

Answer 1

There are several problems with the properties you have defined. I will try to explain each of them one by one. However, you should refer back to the log4j2 manual regarding properties configuration and do your own research to find examples that use log4j2 properties or other questions regarding log4j2 properties to help you when you get stuck and include this information in your question.

You said that only error and fatal levels are displayed on the console. This is due to the fact that you have not defined a root logger. As the log4j2 manual states :

Every configuration must have a root logger. If one is not configured the default root LoggerConfig, which has a level of ERROR and has a Console appender attached, will be used.

Since additivity is true by default and you have not disabled it, all log events are being sent to the default root logger as mentioned above. The result is that only those events which are error or fatal are logged to console since the default root logger's level is ERROR

Now, regarding your properties configuration here are the problems:

1. Your file appenders have invalid attributes "MaxBackupIndex", "MaxFileSize". The following two lines are not applicable to a file appender:

   appender.user.MaxFileSize=5120KB

   appender.user.MaxBackupIndex=10

   Perhaps you wanted a rolling file appender instead? It's not really clear from your question so I commented these out by adding '#' to the front of each line.

2. If you're using log4j2 version 2.6 or greater then you don't need these lines:

   appenders = console, user, system

   Loggers = file

   You didn't specify which version you're using so I assumed you're using the latest in which case these lines are not needed. I commented these lines as well.

3. Both of your appenders use the same name of "LOGFILE". I changed the user appender name to "userLog" and the system appender name to "systemLog". (see full properties later in the answer)

4. You only defined one logger and its name does not match the name you're using to retrieve it. This is why all of your log events go to the default root logger. You have logger.file.name = de.pares.int_plan but de.pares.int_plan is not one of the names you used in your java code to obtain the logger. You used user and system . I corrected these in the properties (see full properties later in the answer).

5. You're missing the '%' before c{1} in the pattern of both file appenders.

6. You have an extra line in your logger definition logger.file.appenderRefs = file that does not appear to be necessary based on the example in the log4j2 manual .

Putting all of these corrections together I arrived at the following properties:

name=PropertiesConfig
property.filename = logs
#Removed the following line since latest log4j2 does not need it
#appenders = console, user, system

appender.console.type = Console
appender.console.name = STDOUT
appender.console.layout.type = PatternLayout
appender.console.layout.pattern = [%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %c{1} - %msg%n

appender.user.type = File
appender.user.name = userLog
appender.user.fileName=${filename}/user.log
appender.user.layout.type=PatternLayout
appender.user.layout.pattern=[%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %c{1} - %msg%n
#Removed attributes that do not apply to file appender
#appender.user.MaxFileSize=5120KB
#appender.user.MaxBackupIndex=10

appender.system.type = File
appender.system.name = systemLog
appender.system.fileName=${filename}/system.log
appender.system.layout.type=PatternLayout
appender.system.layout.pattern=[%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %c{1} - %msg%n
#Removed attributes that do not apply to file appender
#appender.system.MaxFileSize=5120KB
#appender.system.MaxBackupIndex=10

#Removed the following line since latest log4j2 does not need it
#Loggers = file
logger.userFile.name = user
logger.userFile.level = All
logger.userFile.appenderRef.user.ref  = userLog

logger.systemFile.name = system
logger.systemFile.level = All
logger.systemFile.appenderRef.system.ref = systemLog

#Adding the following commented lines for reference - this is how you define the root logger in the properties.
#rootLogger.level = info
#rootLogger.appenderRef.console.ref = STDOUT

To test this configuration I used the following code:

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

public class SomeClass {

    private static Logger userLog = LogManager.getLogger("user");
    private static Logger systemLog = LogManager.getLogger("system");

    public static void main(String[] args){

        systemLog.debug("This is the top of main method");
        if(userLog.isDebugEnabled())
            userLog.debug("This is some debug!");
        userLog.info("Here's some info!");
        userLog.error("Some error happened!");
        systemLog.info("This is the end of main method");
        systemLog.error("woops an error occurred");
    }
}

The result is two log files:

system.log

[DEBUG] 2019-02-16 18:04:04.980 [main] system - This is the top of main method
[INFO ] 2019-02-16 18:04:04.980 [main] system - This is the end of main method
[ERROR] 2019-02-16 18:04:04.980 [main] system - woops an error occurred

user.log

[DEBUG] 2019-02-16 18:04:04.980 [main] user - This is some debug!
[INFO ] 2019-02-16 18:04:04.980 [main] user - Here's some info!
[ERROR] 2019-02-16 18:04:04.980 [main] user - Some error happened!

and console output:

[DEBUG] 2019-02-16 18:04:04.980 [main] system - This is the top of main method
[DEBUG] 2019-02-16 18:04:04.980 [main] user - This is some debug!
[INFO ] 2019-02-16 18:04:04.980 [main] user - Here's some info!
[ERROR] 2019-02-16 18:04:04.980 [main] user - Some error happened!
[INFO ] 2019-02-16 18:04:04.980 [main] system - This is the end of main method
[ERROR] 2019-02-16 18:04:04.980 [main] system - woops an error occurred

To fully understand the console output please refer to the log4j2 manual - the section titled Additivity .

Hope this helps!

Answer 2

Couple of things is see with just a cursory pass at this. I will intersperse comments in-line using # comments

appender.user.type = File
appender.user.name = LOGFILE
#                    ^^^^^^^ This must be distinct - it conflicts with appender.system
appender.user.fileName=${filename}/user.log
appender.user.layout.type=PatternLayout
appender.user.layout.pattern=[%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] c{1} - %msg%n
#                                                         missing % here ^^^^
appender.user.MaxFileSize=5120KB
appender.user.MaxBackupIndex=10

appender.system.type = File
appender.system.name = LOGFILE
#                      ^^^^^^^ This must be distinct - it conflicts with appender.user
appender.system.fileName=${filename}/system.log
appender.system.layout.type=PatternLayout
appender.system.layout.pattern=[%-5level] %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] c{1} - %msg%n
#                                                           missing % here ^^^^
appender.system.MaxFileSize=5120KB
appender.system.MaxBackupIndex=10