GWT 2.6控制台警告

Question

这些警告意味着什么？

[WARN] Server class 'org.eclipse.jetty.servlet.listener.ELContextCleaner' could not be found in the web app, but was found on the system classpath
   [WARN] Adding classpath entry 'file:/Applications/gwt/gwt-2.6.0/gwt-dev.jar' to the web app classpath for this session
   For additional info see: file:/Applications/gwt/gwt-2.6.0/doc/helpInfo/webAppClassPath.html
[WARN] Server class 'org.slf4j.Logger' could not be found in the web app, but was found on the system classpath
   [WARN] Adding classpath entry 'file:/Users/mg/Documents/Grails/GGTS3.5M1/buddyis/lib/gwt/slf4j-api-1.7.5.jar' to the web app classpath for this session
   For additional info see: file:/Applications/gwt/gwt-2.6.0/doc/helpInfo/webAppClassPath.html
[WARN] Server class 'org.slf4j.impl.StaticLoggerBinder' could not be found in the web app, but was found on the system classpath
   [WARN] Adding classpath entry 'file:/Users/mg/Documents/Grails/GGTS3.5M1/buddyis/lib/gwt/mobile/slf4j-log4j12-1.7.5.jar' to the web app classpath for this session
   For additional info see: file:/Applications/gwt/gwt-2.6.0/doc/helpInfo/webAppClassPath.html
[WARN] Server class 'org.apache.log4j.Level' could not be found in the web app, but was found on the system classpath
   [WARN] Adding classpath entry 'file:/Users/mg/Documents/Grails/GGTS3.5M1/buddyis/lib/gwt/mobile/log4j-1.2.17.jar' to the web app classpath for this session
   For additional info see: file:/Applications/gwt/gwt-2.6.0/doc/helpInfo/webAppClassPath.html
log4j:WARN No appenders could be found for logger (org.eclipse.jetty.util.log).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
log4j:WARN No appenders could be found for logger (org.apache.jasper.compiler.JspRuntimeContext).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.

Answer 1

第一组WARNings是因为当你运行dev-mode时,它会启动一个servlet容器(Jetty),默认情况下配置它可以在未找到类时使用项目类路径中的任何库.这些警告对于了解必须在生产中添加到.war工件中的库有用.

第二组WARNings是因为您尚未为项目配置log4j.