Question

我正在尝试在Maven项目中动态设置日志文件名。

我在博客文章之后尝试了很多次，但是未生成日志文件。

经过几次尝试和调试，我发现在数据库调用之前使用System.setProperty设置日志文件名时，便会创建日志文件。

 System.setProperty("logFileName", "E:\\FICO\\logs\\calculate");

但是我想使用从数据库获得的值来设置文件名。

例如：

String ccmValue = "E:\\FICO\\logs\\calculate_" + getCurrentCCMValue(); // DB Call to get the value
System.setProperty("logfilename", ccmValue ); // E:\\FICO\\logs\\calculate_ccmValue.log

如果在数据库调用之后设置了System.setProperty，则不会创建文件。

下面是我的log4j.xml文件：

<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">
<log4j:configuration debug="true"
    xmlns:log4j='http://jakarta.apache.org/log4j/'>

    <appender name="console"
        class="org.apache.log4j.ConsoleAppender">
        <param name="Target" value="System.out" />
        <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern"
                value="%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n" />
        </layout>
    </appender>

    <appender name="fileAppender"
        class="org.apache.log4j.RollingFileAppender">
        <param name="File" value="${logFileName}.log" />
        <param name="maxFileSize" value="1MB" />
        <param name="maxBackupIndex" value="5" />
        <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern"
                value="%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n" />
        </layout>
    </appender>

    <root>
        <priority value="info"></priority>
        <appender-ref ref="console"></appender-ref>
        <appender-ref ref="fileAppender"></appender-ref>
    </root>

</log4j:configuration>

这是控制台日志：

log4j: reset attribute= "false".
log4j: Threshold ="null".
log4j: Level value for root is  [info].
log4j: root level set to INFO
log4j: Class name: [org.apache.log4j.ConsoleAppender]
log4j: Setting property [target] to [System.out].
log4j: Parsing layout of class: "org.apache.log4j.PatternLayout"
log4j: Setting property [conversionPattern] to [%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n].
log4j: Adding appender named [console] to category [root].
log4j: Class name: [org.apache.log4j.RollingFileAppender]
log4j: Setting property [file] to [.log].
log4j: Setting property [maxFileSize] to [1MB].
log4j: Setting property [maxBackupIndex] to [5].
log4j: Parsing layout of class: "org.apache.log4j.PatternLayout"
log4j: Setting property [conversionPattern] to [%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n].
log4j: setFile called: .log, true
log4j: setFile ended
log4j: Adding appender named [fileAppender] to category [root].
2019-07-10 22:58:16 INFO  Version:46 - HHH000412: Hibernate Core {5.4.3.Final}
2019-07-10 22:58:17 INFO  Version:49 - HCANN000001: Hibernate Commons Annotations {5.1.0.Final}
2019-07-10 22:58:18 INFO  ConnectionProviderInitiator:137 - HHH000130: Instantiating explicit connection provider: org.hibernate.connection.C3P0ConnectionProvider
2019-07-10 22:58:18 INFO  C3P0ConnectionProvider:116 - HHH010002: C3P0 using driver: com.mysql.cj.jdbc.Driver at URL: jdbc:mysql://localhost:3306/gentexdba
2019-07-10 22:58:18 INFO  C3P0ConnectionProvider:117 - HHH10001001: Connection properties: {user=root, password=****}
2019-07-10 22:58:18 INFO  C3P0ConnectionProvider:120 - HHH10001003: Autocommit mode: false
2019-07-10 22:58:18 INFO  MLog:126 - MLog clients using log4j logging.

2019-07-10 22:58:18 INFO MLog：126-使用log4j日志记录的MLog客户端。

2019-07-10 22:58:18 INFO  C3P0Registry:248 - Initializing c3p0-0.9.5.3 [built 27-January-2019 00:11:37 -0800; debug? true; trace: 10]
2019-07-10 22:58:18 INFO  C3P0ConnectionProvider:200 - HHH10001007: JDBC isolation level: <unknown>

在发出数据库请求之后，如何使用log4j动态设置日志文件名？

0 个答案: