org.apache.catalina.connector.ResponseFacade.sendRedirect错误处理

出错现象：

严重: Servlet.service() for servlet Login threw exception

java.lang.IllegalStateException

 at org.apache.catalina.connector.ResponseFacade.sendRedirect(ResponseFacade.java:435)

 at com.togethergo.common.servlet.Login.doPost(Login.java:96)

 at javax.servlet.http.HttpServlet.service(HttpServlet.java:710)

 at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)

 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)

 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)

 at com.togethergo.common.filter.PageCharacterEncoding.doFilter(PageCharacterEncoding.java:35)

 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)

 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)

 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)

 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)

 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)

 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)

 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)

 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:263)

 at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)

 at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:584)

 at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)

 at java.lang.Thread.run(Thread.java:595)

 

出错原因：

可能多次调用了HttpServletResponse.sendRedirect(url) 方法。