我在使用velocity时报错了，是不是少了什么包？

Question

Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/log/format/Formatter
at org.apache.velocity.runtime.log.LogManager.createLogSystem(LogManager.java:200)
at org.apache.velocity.runtime.RuntimeInstance.initializeLogger(RuntimeInstance.java:591)
at org.apache.velocity.runtime.RuntimeInstance.init(RuntimeInstance.java:264)
at org.apache.velocity.app.VelocityEngine.init(VelocityEngine.java:118)
at Test2.main(Test2.java:23)

Answer 1

少avalon-logkit。建议用maven管理jar依赖。用denpendency tree，所有包之间的依赖关系一目了然。