2016-03-18 13:07:17.555:WARN:oejuc.AbstractLifeCycle:FAILED o.e.j.w.WebAppContext{/XMJS,file:/D:/Users/Administrator/workspace/.metadata/.plugins/org.eclipse.wst.server.core/tmp2/wtpwebapps/XMJS/},D:UsersAdministratorworkspace.metadata.pluginsorg.eclipse.wst.server.core mp2/wtpwebapps/XMJS: java.lang.NoClassDefFoundError: org/objectweb/asm/ClassVisitor java.lang.NoClassDefFoundError: org/objectweb/asm/ClassVisitor at org.eclipse.jetty.annotations.AnnotationConfiguration.createAnnotationParser(AnnotationConfiguration.java:160) at org.eclipse.jetty.annotations.AnnotationConfiguration.configure(AnnotationConfiguration.java:111) at org.eclipse.jetty.webapp.WebAppContext.configure(WebAppContext.java:468) at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1237)
eclipse配置jetty8.1时启动找不到asm这个jar包，即使在buildpath上添加jar包也不好使，原因：
jetty 8.1libannotations下面有一个org.objectweb.asm-3.1.0.v200803061910.jar就是我们缺失的包，只需把这个包放在jetty 8.1lib下，重新配置jetty就可以了。