Embedded Tomcat 7 problem: concurrent requests lead to Fatal transport error

[Yuhong Qian]

Hi all,

I am using Embedded Tomcat 7 in my java application. The request url to Embedded Tomcat is http://localhost:8091/GetAgentServlet?groupId=1. It works fine if the request is submitted one by one, but excpetion occurred when multiple requests (above 4, for example) are submited simultaneously.

How to solve this problem? Is there any way to configure the concurrent thread number or something?
Any help are highly appreciated.

Fatal transport error: Stream closed
java.io.IOException: Stream closed
at java.io.BufferedInputStream.getBufIfOpen(BufferedInputStream.java:162)
at java.io.BufferedInputStream.read(BufferedInputStream.java:258)
at org.apache.commons.httpclient.HttpParser.readRawLine(HttpParser.java:78)
at org.apache.commons.httpclient.HttpParser.readLine(HttpParser.java:106)
at org.apache.commons.httpclient.HttpConnection.readLine(HttpConnection.java:1116)
at org.apache.commons.httpclient.HttpMethodBase.readStatusLine(HttpMethodBase.java:1973)
at org.apache.commons.httpclient.HttpMethodBase.readResponse(HttpMethodBase.java:1735)
at org.apache.commons.httpclient.HttpMethodBase.execute(HttpMethodBase.java:1098)
at org.apache.commons.httpclient.HttpMethodDirector.executeWithRetry(HttpMethodDirector.java:398)
at org.apache.commons.httpclient.HttpMethodDirector.executeMethod(HttpMethodDirector.java:171)
at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:397)
at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:323)
at ictbox.agi.HttpClientOp.getAgentServlet(HttpClientOp.java:97)
at AutoDialerAgi.service(AutoDialerAgi.java:104)
at org.asteriskjava.fastagi.internal.AgiConnectionHandler.runScript(AgiConnectionHandler.java:144)
at org.asteriskjava.fastagi.internal.AgiConnectionHandler.run(AgiConnectionHandler.java:116)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:636)



Lucy

[Yuhong Qian]

hi,

I am using HTTPClient to access the url ( See the above) , I have been
facing an Intermittent problem with the following exception. Is it a problem with the HTTPClient or a problem with the Embbedded Tomcat?

Fatal transport error: Stream closed
java.io.IOException: Stream closed
at java.io.BufferedInputStream.getBufIfOpen(BufferedInputStream.java:162)
at java.io.BufferedInputStream.read(BufferedInputStream.java:258)
at org.apache.commons.httpclient.HttpParser.readRawLine(HttpParser.java:78)
at org.apache.commons.httpclient.HttpParser.readLine(HttpParser.java:106)
at org.apache.commons.httpclient.HttpConnection.readLine(HttpConnection.java:1116)
at org.apache.commons.httpclient.HttpMethodBase.readStatusLine(HttpMethodBase.java:1973)
at org.apache.commons.httpclient.HttpMethodBase.readResponse(HttpMethodBase.java:1735)
at org.apache.commons.httpclient.HttpMethodBase.execute(HttpMethodBase.java:1098)
at org.apache.commons.httpclient.HttpMethodDirector.executeWithRetry(HttpMethodDirector.java:398)
at org.apache.commons.httpclient.HttpMethodDirector.executeMethod(HttpMethodDirector.java:171)
at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:397)
at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:323)
at ictbox.agi.HttpClientOp.getAgentServlet(HttpClientOp.java:97)
at AutoDialerAgi.service(AutoDialerAgi.java:104)
at org.asteriskjava.fastagi.internal.AgiConnectionHandler.runScript(AgiConnectionHandler.java:144)
at org.asteriskjava.fastagi.internal.AgiConnectionHandler.run(AgiConnectionHandler.java:116)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:636)

Lucy

[Tim Holloway]

Welcome to the JavaRanch, Lucy!

Tomcat doesn't really care what apps do as network clients, allowing for the fact that they should do it relatively quickly and not leave stuff hanging when the request has completed processing (that is, don't spawn child threads and so forth).

Although it's possible that you're having a problem with the data coming back from the remote server, it sounds like your servlet isn't thread-safe. If you are keeping any information in static or class-member variables, they can and will be corrupted when multiple requests are all being handled by the same servlet.