????在項目中日志信息真的是不容忽視，我繼續(xù)跟進我之前的項目，現(xiàn)在開始來添加日志了，首先看一下錯誤信息

11-Apr-2018 17:24:05.786 INFO [RMI TCP Connection(3)-127.0.0.1] org.apache.jasper.servlet.TldScanner.scanJars At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.

MLog initialization issue: slf4j found no binding or threatened to use its (dangerously silent) NOPLogger. We consider the slf4j library not found.

????直接不看了，只看主要的，那為啥要貼出來？貼出來搜索引擎才能在你貼錯誤信息的時候能搜出我寫的啊

? ? 直接看這一段，SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".

????他的意思是這個包SLF4J沒有找到org.slf4j.impl.StaticLoggerBinder這個類，也就是說我們確少依賴，所以我們添加依賴就行了，我們在gradle里面加上這樣的幾段，等待gradle的更新，然后我們重啟tomcat再來看看

compile group: 'org.slf4j', name: 'slf4j-api', version: '1.7.25'compile group: 'org.slf4j', name: 'slf4j-log4j12', version: '1.7.25'compile group: 'org.slf4j', name: 'jcl-over-slf4j', version: '1.7.25'compile group: 'org.slf4j', name: 'jul-to-slf4j', version: '1.7.25'

????現(xiàn)在我們發(fā)現(xiàn)控制臺的日志信息改了

11-Apr-2018 17:31:37.126 INFO [RMI TCP Connection(3)-127.0.0.1] org.apache.jasper.servlet.TldScanner.scanJars At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.

log4j:WARN No appenders could be found for logger (org.springframework.web.context.ContextLoader).
log4j:WARN Please initialize the log4j system properly.

log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.

????現(xiàn)在我們來看這一段log4j:WARN Please initialize the log4j system properly.

????他的意思是要使用這個東西我們還需要對他進行配置，ok，我們現(xiàn)在就來配置他

????我們在reresources文件夾下面新建一個 log4j.properties 文件，這個文件名是固定的，所以就不要想著改啦，文件地址也是classpath的地址，所以也不要想著變啦，當然你可以選擇改掉它里面的配置去實現(xiàn)這樣的功能

????在里面加上下面的這些東西，這些只是一些很簡單的基本的配置，這里我也不做詳細的解釋了，需要更詳細的配置可以參考log4j詳細配置，這篇文章對里面的配置寫的很清楚，感興趣的可以去看看

### set log levels ### log4j.rootLogger=INFO , console , debug , error ### console ### log4j.appender.console=org.apache.log4j.ConsoleAppender log4j.appender.console.Target=System.out log4j.appender.console.layout=org.apache.log4j.PatternLayout log4j.appender.console.layout.ConversionPattern=%-d{yyyy-MM-dd HH\:mm\:ss} [%p]-[%c] %m%n ### log file ### log4j.appender.debug=org.apache.log4j.DailyRollingFileAppender log4j.appender.debug.File=log.log log4j.appender.debug.Append=true log4j.appender.debug.Threshold=INFO log4j.appender.debug.layout=org.apache.log4j.PatternLayout log4j.appender.debug.layout.ConversionPattern=%-d{yyyy-MM-dd HH\:mm\:ss} [%p]-[%c] %m%n ### exception ### log4j.appender.error=org.apache.log4j.DailyRollingFileAppender log4j.appender.error.File=error-log.log log4j.appender.error.Append=true log4j.appender.error.Threshold=ERROR log4j.appender.error.layout=org.apache.log4j.PatternLayout log4j.appender.error.layout.ConversionPattern=%-d{yyyy-MM-dd HH\:mm\:ss} [%p]-[%c] %m%n ###需要聲明，然后下方才可以使druid sql輸出，否則會拋出log4j.error.key not found log4j.appender.stdout=org.apache.log4j.ConsoleAppender log4j.appender.stdout.Target=System.out log4j.appender.stdout.layout=org.apache.log4j.PatternLayout log4j.appender.stdout.layout.ConversionPattern=%d{ISO8601} %l %c%n%p: %m%n ### druid sql ### log4j.logger.druid.sql=warn,stdout log4j.logger.druid.sql.DataSource=warn,stdout log4j.logger.druid.sql.Connection=warn,stdout log4j.logger.druid.sql.Statement=warn,stdout log4j.logger.druid.sql.ResultSet=warn,stdout

????到這里我們的配置已經(jīng)完成，我們需要對他進行測試才行，我就很懶，還是在我之前的Controller立面進行測試了，我現(xiàn)在是在跟進我的項目，實現(xiàn)這個功能和解決問題，大家如果感興趣的話可以去GitHub下載我的項目GitHub傳送門

import org.apache.log4j.Logger;//導入這個包private final static Logger logger = Logger.getLogger (IndexController.class);//這個里面?zhèn)魅氲念惥褪潜绢?#64;RequestMapping("home")public String home() {//調用什么方法就是表示日志的級別logger.info("this.info-log");logger.error("this.error-log");logger.debug("this.debug-log");logger.trace("this.trace-log");return "home";}

????弄完之后，啟動tomcat，敲入地址然后看控制臺輸出的日志信息

????可以看到我寫了四個日志輸出但是只打印出來了兩條信息，這個是因為配置的日志級別，我配置的是INFO，他只輸出INFO和ERROR級別的日志

????到現(xiàn)在為止我們的日志也就完成了，有什么不正確的歡迎前來指導

????轉載請標明出處：https://blog.csdn.net/qq_33733799/article/details/79899929

總結

以上是生活随笔為你收集整理的SpringMVC项目添加日志的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網(wǎng)站內容還不錯，歡迎將生活随笔推薦給好友。