log4j

问题 Forget for a second the question of why on earth would you do such a thing - if, for whatever reason, two FileAppenders are configured with the same file - will this setup work? 回答1: Log4j's FileAppender does not allow for two JVM's writing to the same file. If you try, you'll get a corrupt log file. However, logback, log4j's successor, in prudent mode allows two appenders even in different JVMs to write to the same file. 回答2: It doesn't directly answer your question, but log4*net*'s

问题 I didn't get a definitive answer to this question by Google'ing, so I pose it to the groupthink masterminds and to ensure that a quality answer can be Google-able in the future. Using log4j RollingFileAppender, I can set the maximum size I want the file to reach before rolling over on itself, like so: RollingFileAppender rfa = new RollingFileAppender(); rfa.setMaximumFileSize(500000000); // Sets the max file size to 500MB Now, what if I don't ever want this file to be rolled over? How do I

问题 I maintain an application which acts as a container for multiple individual programs. These programs have their own dedicated logging facility, i.e. everything they log does to a special log file. Nevertheless, application developers seem to love to throw System.out.println and e.printStackTrace calls all over, making it impossible to maintain a clean console when running the container. How can I prevent these applications from polluting System.out and System.err ? Implementation notes: the

问题 I have a problem applying the log4j2.xml auto configuration properly, and I think it has something to do with my folder arrangement. I'm using maven to add log4j2 libs and arrange my projects as follows: - one project to contain all "common" classes, used by server and client side of my system. - another "core" project - the server side application. Both projects use the same general package hierarchy (like com.foo.specific.package ) In the Common project I define a logger wrapper: public

问题 I'm using Hibernate for a personal project. In my project, I have these directory: + conf log4j.properties + bin my classes Using Windows console, I go to project directory (the parent of bin and conf) and I start the application with a command like this: java -cp conf;lib/lib1.jar;lib/lib2.jar;[etc] com.moc.Main My log4j.properties file is this (taken from an hibernate example): log4j.appender.stdout=org.apache.log4j.ConsoleAppender log4j.appender.stdout.Target=System.out log4j.appender

问题 First example: public class Main { private static final Logger logger = LoggerFactory.getLogger(Main.class); public static void main(String[] args) throws Exception { try { throw new RuntimeException(new NullPointerException("NPE")); } catch (RuntimeException e) { logger.error("Error:", e); } } } Output: Error: java.lang.RuntimeException: java.lang.NullPointerException: NPE at Main.main(Main.java:10) In the second example we just add a message to the RuntimeException also: throw new

问题 I need to poll the JVM memory stats of my running application on a regular basis. I'm running a service that does this and writes the stats to the root Logger (I don't have much control over Root Logger usage or not). What I want to do is route just these logging messages to a single appender. This appender should only process logging messages from this one class, and not from any other class. The other appenders shouldn't receive the messages from this one class. So far I have the log

问题 I have a rest service developed with jersey, I have a ContainerRequestFilters for print the request, as follows: <init-param> <param-name>com.sun.jersey.spi.container.ContainerRequestFilters</param-name> <param-value>com.sun.jersey.api.container.filter.LoggingFilter</param-value> </init-param> and I have logger in the post methods using log4j. But the LoggingFilter print in the log different log4j. Is there any way that LogginFilter use the log4j's configuration? I tried this in the log4j.xml

问题 We are using PDFBox to do some PDF reading and manipulations. But during the parsing, I get a bunch of messages like this one: Changing font on <m> from <Arial Bold> to the default font Now how can I disable these? Because a message like this is output on EVERY character of the input if the font is embedded and the log files therefore become pretty unusable. Now changing the overall log level is not an option, because I need the statements from other components. I am using Tomcat 5.5, log4j 1

问题 I'm getting an exception when I try to run my application (in eclipse) complaining about log4j.dtd. Am I meant to have a dtd file if I use the xml configuration for log4j? Caused by: java.io.FileNotFoundException: C:\data\workspace\LDICommon_Trunk\resources\log4j.dtd (The system cannot find the file specified) at java.io.FileInputStream.open(Native Method) 回答1: If you are using XML-based log4j, then yes, you will need the DTD file. Copy this DTD file into your workspace: http://logging.apache