eclipse - 使用velocity时报java.lang.NoClassDefFoundError，是否少了什么包？

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

Less avalon-logkit.
It is recommended to use maven to manage jar dependencies. Using the denpendency tree, the dependencies between all packages are clear at a glance.