Log4j
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Apache Log4j is a versatile, industrial-grade Java logging framework composed of an API, its implementation, and components to assist the deployment for various use cases.
https://logging.apache.org/log4j/2.x/
- 控制日志信息输送的目的地是控制台、文件、GUI 组件，甚至是套接口服务器、NT 的事件记录器、UNIX Syslog 守护进程等
- 控制每一条日志的输出格式
- 通过定义每一条日志信息的级别，更加细致地控制日志的生成过程
ALL < DEBUG < INFO < WARN < ERROR < FATAL < OFF
pom.xml
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
log4j.properties
log4j.rootLogger=INFO,stdout # 第一段表示输出级别, stdout,logfile 表示输出方式，与下面对应 # log4j.rootLogger=Error,stdout,logfile # stdout log4j.appender.stdout=org.apache.log4j.ConsoleAppender log4j.appender.stdout.Target=System.out log4j.appender.stdout.Threshold=DEBUG log4j.appender.stdout.layout=org.apache.log4j.PatternLayout log4j.appender.stdout.layout.ConversionPattern=%d %p [%c] %m%n # logfile log4j.appender.logfile=org.apache.log4j.RollingFileAppender log4j.appender.logfile.File=log/system.log log4j.appender.logfile.MaxFileSize=10mb log4j.appender.logfile.Threshold=Error log4j.appender.logfile.layout=org.apache.log4j.PatternLayout log4j.appender.logfile.layout.ConversionPattern=%d %p [%c] %m%n # Level log4j.logger.org.apache.kafka=Error # 可以指定类输出级别 log4j.logger.org.mybatis=DEBUG log4j.logger.java.sql=DEBUG log4j.logger.java.sql.Statement=DEBUG log4j.logger.java.sql.ResultSet=DEBUG log4j.logger.java.sql.PreparedStatement=DEBUG 如 kafka 中会大量输出 debug 信息，可以指定输出级别或关闭(=OFF)： log4j.logger.org.apache.kafka.clients=Error log4j.logger.org.apache.kafka.common=Error
输出日志类
private static final Logger logger = Logger.getLogger(CLASSNAME.class)
...
logger.info("information...")
public static void log(Object log1) {
Logger logger = Logger.getLogger(Thread.currentThread().getStackTrace()[2].getClassName());
logger.info(log1);
}
slf4j
import org.apache.log4j.PropertyConfigurator;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class BASE {
public static final String VERSION = "v1.21";
static {
PropertyConfigurator.configure("config/log4j.properties");
}
private static final Logger logger = LoggerFactory.getLogger(BASE.class);
public static void test(Object log1) {
logger.info(log1.toString());
logger.warn(log1.toString());
}
}