我不知道大家都尝试过哪种URL模式，但是将servlet映射到
/credentialServlet或
/credentialServlet/*绝对可以运行。
<servlet> <servlet-name>credentialServlet</servlet-name> <servlet-class>com.servlet.CredentialServlet</servlet-class></servlet><servlet-mapping> <servlet-name>credentialServlet</servlet-name> <url-pattern>/credentialServlet</url-pattern></servlet-mapping><welcome-file-list> <welcome-file>credentialServlet</welcome-file></welcome-file-list>
