When I did the graphic verification code, I randomly found a segment of code from the Internet. The result showed this exception. The details are as follows:
(
4361578
MS) [HTTP
-
8080
-
Processor25] error: org. Apache. Catalina. Core. containerbase. [Catalina]. [localhost]. [
/
Xixibar]. [JSP] # invoke: servlet. Service ()
For
Servlet JSP threw exception
Java. Lang. illegalstateexception: getoutputstream () has already been called
For
This
Response
At org. Apache. Catalina. connector. response. getwriter (response. Java:
599
)
At org. Apache. Catalina. connector. responsefacade. getwriter (responsefacade. Java:
195
)
At org. Apache. Jasper. runtime. jspwriterimpl. initout (jspwriterimpl. Java:
124
)
At org. Apache. Jasper. runtime. jspwriterimpl. flushbuffer (jspwriterimpl. Java:
117
)
At org. Apache. Jasper. runtime. pagecontextimpl. Release (pagecontextimpl. Java:
182
)
At org. Apache. Jasper. runtime. jspfactoryimpl. internalreleasepagecontext (jspfactoryimpl. Java:
115
)
At org. Apache. Jasper. runtime. jspfactoryimpl. releasepagecontext (jspfactoryimpl. Java:
75
)
At org. Apache. jsp. image_jsp. _ jspservice (image_jsp.java:
105
)
At org. Apache. Jasper. runtime. httpjspbase. Service (httpjspbase. Java:
97
)
At javax. servlet. http. httpservlet. Service (httpservlet. Java:
802
)
At org. Apache. Jasper. servlet. jspservletwrapper. Service (jspservletwrapper. Java:
334
)
At org. Apache. Jasper. servlet. jspservlet. servicejspfile (jspservlet. Java:
314
)
At org. Apache. Jasper. servlet. jspservlet. Service (jspservlet. Java:
264
)
At javax. servlet. http. httpservlet. Service (httpservlet. Java:
802
)
At org. Apache. Catalina. Core. applicationfilterchain. internaldofilter (applicationfilterchain. Java:
252
)
At org. Apache. Catalina. Core. applicationfilterchain. dofilter (applicationfilterchain. Java:
173
)
At org. Apache. Catalina. Core. standardwrappervalve. Invoke (standardwrappervalve. Java:
213
)
At org. Apache. Catalina. Core. standardcontextvalve. Invoke (standardcontextvalve. Java:
178
)
At org. Apache. Catalina. Core. standardhostvalve. Invoke (standardhostvalve. Java:
126
)
At org. Apache. Catalina. Valves. errorreportvalve. Invoke (errorreportvalve. Java:
105
)
At org. Apache. Catalina. Core. standardenginevalve. Invoke (standardenginevalve. Java:
107
)
At org. Apache. Catalina. connector. coyoteadapter. Service (coyoteadapter. Java:
148
)
At org. Apache. Coyote. http11.http11processor. Process (http11processor. Java:
869
)
At org. Apache. Coyote. http11.http11baseprotocol $ http11connectionhandler. processconnection (http11baseprotocol. Java:
664
)
At org.apache.tomcat.util.net. pooltcpendpoint. processsocket (pooltcpendpoint. Java:
527
)
At org.apache.tomcat.util.net. leaderfollowerworkerthread. Runit (leaderfollowerworkerthread. Java:
80
)
At org. Apache. tomcat. util. threads. threadpool $ controlrunnable. Run (threadpool. Java:
684
)
At java. Lang. thread. Run (thread. Java:
595
)
I didn't understand what was going on at the beginning. I asked Google for help and found the following explanation:
In Tomcat 5, this error occurs in JSP. Generally, the output stream is used in JSP (such as the output image verification code and file download ),
The reason is not properly handled.
The specific reason is
After JSP is compiled into servlet in Tomcat
There is such a piece of code
Finally
...
{
If
(_ Jspxfactory
! =
Null
) _ Jspxfactory. releasepagecontext (_ jspx_page_context );
}
The object used in JSP will be released and response. getwriter () will be called because the method is
Response. getoutputstream () conflict! Therefore, the above exception occurs.
Then, of course, we need to propose a solution. In fact, it's quite simple (not just as some friends said
--
Delete all spaces and carriage return characters in JSP ),
Call the following two lines of code after the output stream is used:
Out. Clear ();
Out
=
Pagecontext. pushbody ();
Two lines of code are added in this method, and it is OK!
