创建Dynamic web module version这个选项默认成了3.0,
按照老规范,应该是在eclipse的WebContent \ WEB-INF \ 目录下创建web.xml的
而新规范是可以不用web.xml的,如tomcat 7.0就支持新规范,
这样相关的servlet配置会以注解的形式直接写到代码里面了,比如@WebServlet。
当然如果你用老的项目导入,可以选择Dynamic web module version这个选项设成2.5,这样就自动有web.xml生成了。
或者看下地址栏是不是地址不正确的。有时地址不正确也会这样。
今天在做一个实训的时候,也发现打开JSP页面显示404.找了好久,才发现是一个servlet中少了一个“/”
加上后,一切正常 -----20130110
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WVblyiWFuavyrCcdL6CGiRLuu+UdeLjQlaiLcExDcSfLEhXnLeEvA4jRNfjvObySutuGBt8W9Pj8+fle7cIltbxPpQaVEd4oeS41t+XvHjEt3aIi17sKazUJcWPjB0+1anRTxErDnSNqqyu5fW2kL4hJ/Z/HGki0mAuET6npj0glXLougy3/bEKTgz1xq/mfn7zkT1eQuxg6J3VlkFMHR71amlE+ZniOhVqa+IGpVXfamTtufH5f/SUhpiy7ahaAAAAABJRU5ErkJggg==)