The or for must include junit.jar if not in Ant's own classpath

The <classpath> or <modulepath> for <junit> must include junit.jar if not in Ant's own classpath

復制junit.jar到ANT_HOME/lib目錄下，重新刷新eclipse中的配置：

重新執行mvn test，或者直接執行build.xml的ant腳本。錯誤提示消失。