Log4j常用配置及使用
2016-12-14
目录
1
2 2.1 2.2 2.3 3 3.1 3.2 3.3 4 4.1 4.2 4.31 添加log4j依赖
maven的pom.xml文件中添加log4j依赖
log4j log4j 1.2.16 provided
2 使用代码配置并调用log
2.1 代码配置LogConfiguration.java
import java.util.Properties;import org.apache.log4j.PropertyConfigurator;public class LogConfiguration { public static void initLog(String logFilePath){ //声明日志文件存储路径以及文件名、格式 Properties prop = new Properties(); //配置日志输出的格式 prop.setProperty("log4j.rootLogger","info, toConsole, toFile"); prop.setProperty("log4j.appender.file.encoding","UTF-8" ); prop.setProperty("log4j.appender.toConsole","org.apache.log4j.ConsoleAppender"); prop.setProperty("log4j.appender.toConsole.Target","System.out"); prop.setProperty("log4j.appender.toConsole.layout","org.apache.log4j.PatternLayout "); prop.setProperty("log4j.appender.toConsole.layout.ConversionPattern","[%d{yyyy-MM-dd HH:mm:ss}] [%p] %m%n"); prop.setProperty("log4j.appender.toFile.file", logFilePath); //每天产生一个日志文件 prop.setProperty("log4j.appender.toFile", "org.apache.log4j.DailyRollingFileAppender"); //服务器启动日志是追加，false：服务器启动后会生成日志文件把老的覆盖掉 prop.setProperty("log4j.appender.toFile.Append","true"); prop.setProperty("log4j.appender.toFile.Threshold", "info"); prop.setProperty("log4j.appender.toFile.layout", "org.apache.log4j.PatternLayout"); prop.setProperty("log4j.appender.toFile.layout.ConversionPattern", "[%d{yyyy-MM-dd HH:mm:ss}] [%p] %m%n"); //[2017-03-31 14:10:44] [ERROR] HttpResponseAnalyze:31 - Not equal //prop.setProperty("log4j.appender.toFile.layout.ConversionPattern", "[%d{yyyy-MM-dd HH:mm:ss}] [%p] %c{1}:%L - %m%n"); //设置每天生成一个文件名后添加的名称,备份名称：年月日.log prop.setProperty("log4j.appender.toFile.DatePattern","'.'yyyy-MM-dd'.log'"); //使配置生效 PropertyConfigurator.configure(prop); } }
2.2 调用
import org.apache.log4j.Logger;public class TestLog { static Logger logger = Logger.getLogger(TestLog.class.getName()); public static void main(String[] args) { LogConfiguration.initLog("D:\\log\\result.log"); logger.info("log info"); logger.warn("log warn"); logger.error("log error"); try { Thread.sleep(2000); } catch(Exception ex) {} logger.info("log1 info"); logger.warn("log1 warn"); logger.error("log1 error"); }} 2.3 结果
输出到Ecliplse的Console界面和文件D:\log\result.log中，内容如下：
[2016-12-14 16:03:34] [INFO] log info[2016-12-14 16:03:34] [WARN] log warn[2016-12-14 16:03:34] [ERROR] log error[2016-12-14 16:03:36] [INFO] log1 info[2016-12-14 16:03:36] [WARN] log1 warn[2016-12-14 16:03:36] [ERROR] log1 error
另外，由于配置了每天生成一个备份，系统时间切一天后日后，再运行，原先的result.log会变成result.log.2016-12-13.log，新的日志会重新放到新建的日志文件result.log
3 使用Properties文件配置并调用log
3.1 文件配置log4j.properties
log4j.rootLogger=INFO, toConsole, toFile log4j.appender.file.encoding=UTF-8log4j.appender.toConsole=org.apache.log4j.ConsoleAppender log4j.appender.toConsole.Target=System.out log4j.appender.toConsole.layout=org.apache.log4j.PatternLayout log4j.appender.toConsole.layout.ConversionPattern=[%d{yyyy-MM-dd HH:mm:ss}] [%p] %m%n log4j.appender.toFile.file=D:\\log\\result.log #Daily one log filelog4j.appender.toFile=org.apache.log4j.DailyRollingFileAppender log4j.appender.toFile.Append=true log4j.appender.toFile.Threshold=info log4j.appender.toFile.layout=org.apache.log4j.PatternLayoutlog4j.appender.toFile.layout.ConversionPattern=[%d{yyyy-MM-dd HH:mm:ss}] [%p] %m%nlog4j.appender.toFile.DatePattern='.'yyyy-MM-dd'.log' 3.2 调用
import org.apache.log4j.Logger;import org.apache.log4j.PropertyConfigurator;public class TestLog { static Logger logger = Logger.getLogger(TestLog.class.getName()); public static void main(String[] args) { PropertyConfigurator.configure( "D:\\Users\\...\\config\\log4j.properties" ); logger.info("log info"); logger.warn("log warn"); logger.error("log error"); try { Thread.sleep(2000); } catch(Exception ex) {} logger.info("log1 info"); logger.warn("log1 warn"); logger.error("log1 error"); }} 3.3 结果
和上面一致
4 按输出级别的种类保存内容到不同目的地
从高到低：ERROR、WARN、INFO、DEBUG
- ERROR 为严重错误 主要是程序的错误
- WARN 为一般警告，比如session丢失
- INFO 为一般要显示的信息，比如登录登出
- DEBUG 为程序的调试信息
4.1 文件配置log4j.properties
log4j.rootLogger=INFO, toConsole log4j.appender.file.encoding=UTF-8log4j.appender.toConsole=org.apache.log4j.ConsoleAppender log4j.appender.toConsole.Target=System.out log4j.appender.toConsole.layout=org.apache.log4j.PatternLayout log4j.appender.toConsole.layout.ConversionPattern=[%d{yyyy-MM-dd HH:mm:ss}] [%p] %m%n log4j.logger.myError=ERROR, toFile log4j.appender.toFile.file=D:\\log\\Errors.log #Daily one log filelog4j.appender.toFile=org.apache.log4j.DailyRollingFileAppender log4j.appender.toFile.Append=true log4j.appender.toFile.Threshold=info log4j.appender.toFile.layout=org.apache.log4j.PatternLayoutlog4j.appender.toFile.layout.ConversionPattern=[%d{yyyy-MM-dd HH:mm:ss}] [%p] %m%nlog4j.appender.toFile.DatePattern='.'yyyy-MM-dd'.log' 4.2 调用
import org.apache.log4j.Logger;import org.apache.log4j.PropertyConfigurator;public class TestLog { static Logger logger = Logger.getLogger(TestLog.class.getName()); static Logger errorLogger=Logger.getLogger("myError"); public static void main(String[] args) { PropertyConfigurator.configure( "D:\\Users\\...\\config\\log4j.properties" ); logger.info("log info"); logger.warn("log warn"); logger.error("log error"); errorLogger.info("myError info"); errorLogger.warn("myError warn"); errorLogger.error("myError error"); }} 4.3 结果
Eclipse的Console界面
[2016-12-13 17:45:06] [INFO] log info [2016-12-13 17:45:06] [WARN] log warn [2016-12-13 17:45:06] [ERROR] log error [2016-12-13 17:45:06] [ERROR] myError error
Errors.log
[2016-12-13 17:45:06] [ERROR] myError error
参考
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//设置每天生成一个文件名后添加的名称,备份名称：年月日.log