java - 动态命名 log4j 日志文件 - 有效，但 setFile() 并非没有异常(exception)

Question

我有一个为个人客户运行的程序。每个客户都有一个帐户代码(我们称之为起始代码)。帐户代码通过命令行参数传递给程序。我收到以下异常返回给我，顺便说一下，这不会导致程序崩溃，它会愉快地进行。我想按客户帐户分离日志记录，这似乎有效。我的日志文件将被创建为“Balancer_990004.log”，并且日志消息肯定会在创建 Balancer_990004.log.7 时建立，但是，并非没有这个异常(exception)。在这个问题上抓我的头。我已经包含了 log4j.properties 位和代码位。

log4j:ERROR setFile(null,true) call failed.
java.io.FileNotFoundException:  (A file or directory in the path name does not exist.)
 at java.io.FileOutputStream.openAppend(Native Method)
 at java.io.FileOutputStream.<init>(FileOutputStream.java:203)
 at java.io.FileOutputStream.<init>(FileOutputStream.java:127)
 at org.apache.log4j.FileAppender.setFile(FileAppender.java:294)
 at org.apache.log4j.RollingFileAppender.setFile(RollingFileAppender.java:207)
 at org.apache.log4j.FileAppender.activateOptions(FileAppender.java:165)
 at org.apache.log4j.config.PropertySetter.activate(PropertySetter.java:307)
 at org.apache.log4j.config.PropertySetter.setProperties(PropertySetter.java:172)
 at org.apache.log4j.config.PropertySetter.setProperties(PropertySetter.java:104)
 at org.apache.log4j.PropertyConfigurator.parseAppender(PropertyConfigurator.java:809)
 at org.apache.log4j.PropertyConfigurator.parseCategory(PropertyConfigurator.java:735)
 at org.apache.log4j.PropertyConfigurator.parseCatsAndRenderers(PropertyConfigurator.java:639)
 at org.apache.log4j.PropertyConfigurator.doConfigure(PropertyConfigurator.java:504)
 at org.apache.log4j.PropertyConfigurator.doConfigure(PropertyConfigurator.java:547)
 at org.apache.log4j.helpers.OptionConverter.selectAndConfigure(OptionConverter.java:483)
 at org.apache.log4j.LogManager.<clinit>(LogManager.java:127)
 at java.lang.J9VMInternals.initializeImpl(Native Method)
 at java.lang.J9VMInternals.initialize(J9VMInternals.java:200)
 at org.apache.log4j.Logger.getLogger(Logger.java:117)
 at Balancer.<init>(Balancer.java:292)
 at Balancer.main(Balancer.java:2370)

*** Sample bit from log4j.properties.  The name of the Java program in question is "Balancer" ***

log4j.rootLogger=debug, devnull        
log4j.logger.Balancer=info, BalancerLog

log4j.appender.BalancerLog=org.apache.log4j.RollingFileAppender
log4j.appender.BalancerLog.File=${balancer.log}                
log4j.appender.BalancerLog.MaxFileSize=10000KB                                
log4j.appender.BalancerLog.MaxBackupIndex=10                                  
log4j.appender.BalancerLog.layout=org.apache.log4j.PatternLayout              
log4j.appender.BalancerLog.layout.ConversionPattern=%5p %d [%t] (%F:%L) - %m%n

*** How I'm building my log filename and initializing the Logger ***

public class Balancer {
    static Logger log = null;
    ....

// In constructor...

StringBuilder logName = new StringBuilder("Balancer_");
logName.append(startCode.toString());
logName.append(".log");

// Hopefully in log4j.properties our appender section contains this line:
// log4j.appender.BalancerLog.File=${balancer.log}.  This ${} bit means to get a system property to set the log file
// name.  We set that system property here, then initialize the Logger object.
System.setProperty("balancer.log", logName.toString()); 

// This is line 292 in the exception trace.
log = Logger.getLogger(Balancer.class);

Answer 1

如果可以切换到logback，建议使用SiftingAppender相反。这种使用 log4j 的调整是不自然的。