添加jar包,log4j-1.2.17.jar 写配置文件,log4j.properties 创建一个log4j对象
log4j.rootLogger =debug,stdout log4j.logger.com.mingsoft=debug log4j.appender.stdout = org.apache.log4j.ConsoleAppender log4j.appender.stdout.layout = org.apache.log4j.PatternLayout log4j.appender.stdout.layout.ConversionPattern = %d{ABSOLUTE} %5p %c{1}:%L - %m%n
private static Logger logger = Logger.getLogger(“你的类名”.class); logger.debug(“hello world!”);