错误如下: javax.servlet.ServletException: requested URL string is null at weblogic.servlet.jsp.PageContextImpl.getRD(PageContextImpl.java:109) at weblogic.servlet.jsp.PageContextImpl.forward(PageContextImpl.java:148) at weblogic.servlet.jsp.PageContextImpl.handlePageException(PageContextImpl.java:395) at jsp_servlet.__index._jspService(__index.java:708) at weblogic.servlet.jsp.JspBase.service(JspBase.java:34) at weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:225) at weblogic.servlet.internal.StubSecurityHelper.invokeServlet(StubSecurityHelper.java:127) at weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:272) at weblogic.servlet.internal.TailFilter.doFilter(TailFilter.java:26) at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:42) at com.codeluck.util.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:170) at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:42) at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3151) at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321) at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:121) at weblogic.servlet.internal.WebAppServletContext.securedExecute(WebAppServletContext.java:1973) at weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:1880) at weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1310) at weblogic.work.ExecuteThread.execute(ExecuteThread.java:207) at weblogic.work.ExecuteThread.run(ExecuteThread.java:179)