我们自己的系统中使用了logback这个日志系统

我们的系统使用了A.jar，A.jar中使用的日志系统为log4j

我们的系统又使用了B.jar，B.jar中使用的日志系统为slf4j-simple

<dependency><groupId>org.slf4j</groupId><artifactId>slf4j-api</artifactId><version>1.7.30</version></dependency><dependency><groupId>org.slf4j</groupId><artifactId>slf4j-log4j12</artifactId><version>1.7.30</version></dependency>

### 设置,文件必须放到这里目录###### 把指定级别以上的日志信息输出到指定的一个或者多个位置。把DEBUG以上的日志输出到Console和File#Console和File是自己自定义的名称,可以配置更多需要输出的目录#OFF、FATAL、ERROR、WARN、INFO、DEBUG、ALL 紧急程度依次降低。all里面会包括了他上面的所有日志。debug里面会包含上面的所有日志。log4j.rootLogger = DEBUG,Console,File### 输出信息到控制抬 ###log4j.appender.Console = org.apache.log4j.ConsoleAppenderlog4j.appender.Console.Threshold = DEBUGlog4j.appender.Console.Target=System.outlog4j.appender.Console.Encoding=UTF-8log4j.appender.Console.layout = org.apache.log4j.PatternLayoutlog4j.appender.Console.layout.ConversionPattern = [%-5p] %d{yyyy-MM-dd HH:mm:ss,SSS} method:%l%n%m%n### 输出DEBUG 级别以上的日志到=E://logs/debug.log ###log4j.appender.File = org.apache.log4j.DailyRollingFileAppender#相对路径，d:/logs/debug.log#如果写成这个：logs/debug.log ，那么log文件就在： tomcat85\bin\logs目录下面#${log4jFileName}在项目启动的时候设置了log4j.appender.File.File = logs/${log4jFileName}/info.loglog4j.appender.File.Append = truelog4j.appender.File.Threshold = INFO#一天生成一个日志文件log4j.appender.File.datePattern = '_'yyyy-MM-dd'.log'log4j.appender.File.layout = org.apache.log4j.PatternLayoutlog4j.appender.File.layout.ConversionPattern = %-d{yyyy-MM-dd HH:mm:ss}  [ %t:%r ] - [ %p ]  %m%n

public void initLog4j(ServletContextEvent servletContextEvent) {//获取项目名称String prefix = servletContextEvent.getServletContext().getRealPath("/");//在系统变量里面设置log4jFilename,用来指定日志文件的路径System.setProperty("log4jFileName", servletContextEvent.getServletContext().getContextPath());String customerLog4jLocation = servletContextEvent.getServletContext().getInitParameter("log4jLocation");if (StringUtils.isEmpty(customerLog4jLocation)) {customerLog4jLocation = prefix + "WEB-INF\\classes\\log4j\\log4j.properties";} else {PathMatchingResourcePatternResolver resolver = new PathMatchingResourcePatternResolver(new PathMatchingResourcePatternResolver());try {Resource[] resources = resolver.getResources(customerLog4jLocation);PropertyConfigurator.configure(resources[0].getInputStream());customerLog4jLocation = resources[0].getFile().getAbsolutePath();} catch (IOException e) {e.printStackTrace();customerLog4jLocation = prefix + "WEB-INF\\classes\\log4j\\log4j.properties";}}PropertyConfigurator.configure(customerLog4jLocation);logger.debug("lsx log4j properties location:" + customerLog4jLocation);}

<context-param><param-name>log4jLocation</param-name><!--重新定位log4j配置文件位置--><param-value>classpath:log4j/log4j.properties</param-value></context-param>

private final Logger log = LoggerFactory.getLogger(Main.class);public static void main(String[] args) {log.debug("debug");log.info("info");log.error("error");}