[appengine-java] Get execution duration of an asynchronous urlfetch
Hello, I'm playing with async urlfetch. My ispiration was Ikai at http://ikaisays.com/2010/06/29/using-asynchronous-urlfetch-on-java-app-engine/ I run some request in parallel. All works fine. But now I'd like to get info about execution time of each request. The target URLs I call are different so the response time are very different. I read the documentation but HTTPResponse does not expose a execution duration or similar value. Any idea? Fabrizio -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: Creation of owned one-to-many problem
Thank you prabu, that worked :) I knew it is something silly. Problem solved. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Semaphores/ LinkedBlockingQueue on GAE for java
In my application an embedded device (no public IP) should connect to the GAE in order to obtain some data from it. The data are provided by the web browser. The whole data-passing process looks like: web browser - GAE - embedded standalone device I developed a servlet the device connects to. It issues the HTTP GET. On the other side the web browser sends data using standard GWT RemoteServiceServlet. In case there is no data for the device the doGet method in the servlet should stop for some seconds until user enters data or time out expires. I'm trying to use LinkedBlockingQueue to pass data between two servlets. It does not work unfortunately. Seems like the GAE launches new JVM for concurrent requests... I pushed the LinkedBlockingQueue into memcache and get it by name from concurrent requests. Still does not work. Memcache returns NOTnull. But there are no data in the queue. In order to investigate my issue I've made some tests with the semaphore. Pushed the semaphore to the memcache and made some concurrent operations ... - does not work - one process does not release the other... The problem occurs on GAE only. The whole mechanism works on the development server. Is there any way to stop/freeze one process (in the doGet method in servlet) and unblock it by another one ? Or... Is there any other way to solve my problem ? Thank you for any suggestions. Artur -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: Semaphores/ LinkedBlockingQueue on GAE for java
Hi, LinkedBlokingQueue is part of JRE WhiteList: http://code.google.com/appengine/docs/java/jrewhitelist.html. So, you can use it. But, I dont see the need. Why don't you just from on the datastore on 1 side and read from it on the other. It would be very simple and rely on the most basic (i.e solid) mechanism of gae. (I would recommend Objectify for ds read/ write) As you have network round-trips, the read / write time will be negligible even it can seem high compared to an in-memory mechanism like a Queue. regards didier On Jan 29, 1:51 pm, arturad artur.dow...@googlemail.com wrote: In my application an embedded device (no public IP) should connect to the GAE in order to obtain some data from it. The data are provided by the web browser. The whole data-passing process looks like: web browser - GAE - embedded standalone device I developed a servlet the device connects to. It issues the HTTP GET. On the other side the web browser sends data using standard GWT RemoteServiceServlet. In case there is no data for the device the doGet method in the servlet should stop for some seconds until user enters data or time out expires. I'm trying to use LinkedBlockingQueue to pass data between two servlets. It does not work unfortunately. Seems like the GAE launches new JVM for concurrent requests... I pushed the LinkedBlockingQueue into memcache and get it by name from concurrent requests. Still does not work. Memcache returns NOTnull. But there are no data in the queue. In order to investigate my issue I've made some tests with the semaphore. Pushed the semaphore to the memcache and made some concurrent operations ... - does not work - one process does not release the other... The problem occurs on GAE only. The whole mechanism works on the development server. Is there any way to stop/freeze one process (in the doGet method in servlet) and unblock it by another one ? Or... Is there any other way to solve my problem ? Thank you for any suggestions. Artur -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: Semaphores/ LinkedBlockingQueue on GAE for java
Hi, Forgot: you can use Thread.sleep() to wait (java.lang.Thread is also part of the JRE) regards didier On Jan 29, 3:35 pm, Didier Durand durand.did...@gmail.com wrote: Hi, LinkedBlokingQueue is part of JRE WhiteList:http://code.google.com/appengine/docs/java/jrewhitelist.html. So, you can use it. But, I dont see the need. Why don't you just from on the datastore on 1 side and read from it on the other. It would be very simple and rely on the most basic (i.e solid) mechanism of gae. (I would recommend Objectify for ds read/ write) As you have network round-trips, the read / write time will be negligible even it can seem high compared to an in-memory mechanism like a Queue. regards didier On Jan 29, 1:51 pm, arturad artur.dow...@googlemail.com wrote: In my application an embedded device (no public IP) should connect to the GAE in order to obtain some data from it. The data are provided by the web browser. The whole data-passing process looks like: web browser - GAE - embedded standalone device I developed a servlet the device connects to. It issues the HTTP GET. On the other side the web browser sends data using standard GWT RemoteServiceServlet. In case there is no data for the device the doGet method in the servlet should stop for some seconds until user enters data or time out expires. I'm trying to use LinkedBlockingQueue to pass data between two servlets. It does not work unfortunately. Seems like the GAE launches new JVM for concurrent requests... I pushed the LinkedBlockingQueue into memcache and get it by name from concurrent requests. Still does not work. Memcache returns NOTnull. But there are no data in the queue. In order to investigate my issue I've made some tests with the semaphore. Pushed the semaphore to the memcache and made some concurrent operations ... - does not work - one process does not release the other... The problem occurs on GAE only. The whole mechanism works on the development server. Is there any way to stop/freeze one process (in the doGet method in servlet) and unblock it by another one ? Or... Is there any other way to solve my problem ? Thank you for any suggestions. Artur -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Re: Semaphores/ LinkedBlockingQueue on GAE for java
The external device polls for data from GAE. It is not specified when the data arrives. To describe it more clearly. The device is a GSM modem device that sends an SMS on the user request. The user launches a web browser and writes a mobile phone number. The browser sends data to the GAE and the sms should be send immediately So I cannot specify how long I can wait in Thread.sleep(). You mention about Objectify. I use that library but I'm quite new to it. Does it have the mechanism that works like: process A waits for data until data into database arrives or timeout expires process B puts the data into database process a continues processing the data inserted by process B ? On Sat, Jan 29, 2011 at 3:59 PM, Didier Durand durand.did...@gmail.comwrote: Hi, Forgot: you can use Thread.sleep() to wait (java.lang.Thread is also part of the JRE) regards didier On Jan 29, 3:35 pm, Didier Durand durand.did...@gmail.com wrote: Hi, LinkedBlokingQueue is part of JRE WhiteList: http://code.google.com/appengine/docs/java/jrewhitelist.html. So, you can use it. But, I dont see the need. Why don't you just from on the datastore on 1 side and read from it on the other. It would be very simple and rely on the most basic (i.e solid) mechanism of gae. (I would recommend Objectify for ds read/ write) As you have network round-trips, the read / write time will be negligible even it can seem high compared to an in-memory mechanism like a Queue. regards didier On Jan 29, 1:51 pm, arturad artur.dow...@googlemail.com wrote: In my application an embedded device (no public IP) should connect to the GAE in order to obtain some data from it. The data are provided by the web browser. The whole data-passing process looks like: web browser - GAE - embedded standalone device I developed a servlet the device connects to. It issues the HTTP GET. On the other side the web browser sends data using standard GWT RemoteServiceServlet. In case there is no data for the device the doGet method in the servlet should stop for some seconds until user enters data or time out expires. I'm trying to use LinkedBlockingQueue to pass data between two servlets. It does not work unfortunately. Seems like the GAE launches new JVM for concurrent requests... I pushed the LinkedBlockingQueue into memcache and get it by name from concurrent requests. Still does not work. Memcache returns NOTnull. But there are no data in the queue. In order to investigate my issue I've made some tests with the semaphore. Pushed the semaphore to the memcache and made some concurrent operations ... - does not work - one process does not release the other... The problem occurs on GAE only. The whole mechanism works on the development server. Is there any way to stop/freeze one process (in the doGet method in servlet) and unblock it by another one ? Or... Is there any other way to solve my problem ? Thank you for any suggestions. Artur -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Re: Semaphores/ LinkedBlockingQueue on GAE for java
Sounds like you need more of a Push style. Checkout the Channel API or the XMPP api. On Sat, Jan 29, 2011 at 1:47 PM, Artur Downar artur.dow...@googlemail.comwrote: The external device polls for data from GAE. It is not specified when the data arrives. To describe it more clearly. The device is a GSM modem device that sends an SMS on the user request. The user launches a web browser and writes a mobile phone number. The browser sends data to the GAE and the sms should be send immediately So I cannot specify how long I can wait in Thread.sleep(). You mention about Objectify. I use that library but I'm quite new to it. Does it have the mechanism that works like: process A waits for data until data into database arrives or timeout expires process B puts the data into database process a continues processing the data inserted by process B ? On Sat, Jan 29, 2011 at 3:59 PM, Didier Durand durand.did...@gmail.comwrote: Hi, Forgot: you can use Thread.sleep() to wait (java.lang.Thread is also part of the JRE) regards didier On Jan 29, 3:35 pm, Didier Durand durand.did...@gmail.com wrote: Hi, LinkedBlokingQueue is part of JRE WhiteList: http://code.google.com/appengine/docs/java/jrewhitelist.html. So, you can use it. But, I dont see the need. Why don't you just from on the datastore on 1 side and read from it on the other. It would be very simple and rely on the most basic (i.e solid) mechanism of gae. (I would recommend Objectify for ds read/ write) As you have network round-trips, the read / write time will be negligible even it can seem high compared to an in-memory mechanism like a Queue. regards didier On Jan 29, 1:51 pm, arturad artur.dow...@googlemail.com wrote: In my application an embedded device (no public IP) should connect to the GAE in order to obtain some data from it. The data are provided by the web browser. The whole data-passing process looks like: web browser - GAE - embedded standalone device I developed a servlet the device connects to. It issues the HTTP GET. On the other side the web browser sends data using standard GWT RemoteServiceServlet. In case there is no data for the device the doGet method in the servlet should stop for some seconds until user enters data or time out expires. I'm trying to use LinkedBlockingQueue to pass data between two servlets. It does not work unfortunately. Seems like the GAE launches new JVM for concurrent requests... I pushed the LinkedBlockingQueue into memcache and get it by name from concurrent requests. Still does not work. Memcache returns NOTnull. But there are no data in the queue. In order to investigate my issue I've made some tests with the semaphore. Pushed the semaphore to the memcache and made some concurrent operations ... - does not work - one process does not release the other... The problem occurs on GAE only. The whole mechanism works on the development server. Is there any way to stop/freeze one process (in the doGet method in servlet) and unblock it by another one ? Or... Is there any other way to solve my problem ? Thank you for any suggestions. Artur -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Re: Semaphores/ LinkedBlockingQueue on GAE for java
I forgot to ask something:
You said that the LinkedBlokingQueue is on the whitelist and should work on
GAE.
What is the way to pass the object betwean the JVMs/processes ?
I use the memcache and it does not solve my problem.
Cache cache;
try {
cache =
CacheManager.getInstance().getCacheFactory().createCache(Collections.emptyMap());
Semaphore toModemSem = (Semaphore)cache.get(toModemSem);
if (toModemSem == null) {
log.info(memcache returns null);
toModemSem = new Semaphore(0);
cache.put(toModemSem, toModemSem);
}
toModemSem.release();
...
Sorry my example is about the Semaphore. But I do the same with
LinkedBlokingQueue the queue. And both does not work.
Do I use the memcache correctly ?
On Sat, Jan 29, 2011 at 9:47 PM, Artur Downar
artur.dow...@googlemail.comwrote:
The external device polls for data from GAE.
It is not specified when the data arrives. To describe it more clearly. The
device is a GSM modem device that sends an SMS on the user request.
The user launches a web browser and writes a mobile phone number. The
browser sends data to the GAE and the sms should be send immediately
So I cannot specify how long I can wait in Thread.sleep().
You mention about Objectify. I use that library but I'm quite new to it.
Does it have the mechanism that works like:
process A waits for data until data into database arrives or timeout
expires
process B puts the data into database
process a continues processing the data inserted by process B
?
On Sat, Jan 29, 2011 at 3:59 PM, Didier Durand durand.did...@gmail.comwrote:
Hi,
Forgot: you can use Thread.sleep() to wait (java.lang.Thread is also
part of the JRE)
regards
didier
On Jan 29, 3:35 pm, Didier Durand durand.did...@gmail.com wrote:
Hi,
LinkedBlokingQueue is part of JRE WhiteList:
http://code.google.com/appengine/docs/java/jrewhitelist.html. So, you
can use it.
But, I dont see the need. Why don't you just from on the datastore on
1 side and read from it on the other. It would be very simple and rely
on the most basic (i.e solid) mechanism of gae. (I would recommend
Objectify for ds read/ write)
As you have network round-trips, the read / write time will be
negligible even it can seem high compared to an in-memory mechanism
like a Queue.
regards
didier
On Jan 29, 1:51 pm, arturad artur.dow...@googlemail.com wrote:
In my application an embedded device (no public IP) should connect to
the GAE in order to obtain some data from it. The data are provided by
the web browser.
The whole data-passing process looks like:
web browser - GAE -
embedded standalone device
I developed a servlet the device connects to. It issues the HTTP GET.
On the other side the web browser sends data using standard GWT
RemoteServiceServlet.
In case there is no data for the device the doGet method in the
servlet should stop for some seconds until user enters data or time
out expires.
I'm trying to use LinkedBlockingQueue to pass data between two
servlets. It does not work unfortunately. Seems like the GAE launches
new JVM for concurrent requests... I pushed the LinkedBlockingQueue
into memcache and get it by name from concurrent requests. Still does
not work. Memcache returns NOTnull. But there are no data in the
queue.
In order to investigate my issue I've made some tests with the
semaphore. Pushed the semaphore to the memcache and made some
concurrent operations ... - does not work - one process does not
release the other...
The problem occurs on GAE only. The whole mechanism works on the
development server.
Is there any way to stop/freeze one process (in the doGet method in
servlet) and unblock it by another one ?
Or... Is there any other way to solve my problem ?
Thank you for any suggestions.
Artur
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Re: [appengine-java] Re: Semaphores/ LinkedBlockingQueue on GAE for java
Thank you. I took a brief look on channel API and it seems I it is the thing I need. I have a small question. The modem device is a java embedded device and it has no public IP. There is no javascript on it. Only java. Is it enough for GAE channel API to communicate with it ? On Sat, Jan 29, 2011 at 9:49 PM, Stephen Johnson onepagewo...@gmail.comwrote: Sounds like you need more of a Push style. Checkout the Channel API or the XMPP api. On Sat, Jan 29, 2011 at 1:47 PM, Artur Downar artur.dow...@googlemail.com wrote: The external device polls for data from GAE. It is not specified when the data arrives. To describe it more clearly. The device is a GSM modem device that sends an SMS on the user request. The user launches a web browser and writes a mobile phone number. The browser sends data to the GAE and the sms should be send immediately So I cannot specify how long I can wait in Thread.sleep(). You mention about Objectify. I use that library but I'm quite new to it. Does it have the mechanism that works like: process A waits for data until data into database arrives or timeout expires process B puts the data into database process a continues processing the data inserted by process B ? On Sat, Jan 29, 2011 at 3:59 PM, Didier Durand durand.did...@gmail.comwrote: Hi, Forgot: you can use Thread.sleep() to wait (java.lang.Thread is also part of the JRE) regards didier On Jan 29, 3:35 pm, Didier Durand durand.did...@gmail.com wrote: Hi, LinkedBlokingQueue is part of JRE WhiteList: http://code.google.com/appengine/docs/java/jrewhitelist.html. So, you can use it. But, I dont see the need. Why don't you just from on the datastore on 1 side and read from it on the other. It would be very simple and rely on the most basic (i.e solid) mechanism of gae. (I would recommend Objectify for ds read/ write) As you have network round-trips, the read / write time will be negligible even it can seem high compared to an in-memory mechanism like a Queue. regards didier On Jan 29, 1:51 pm, arturad artur.dow...@googlemail.com wrote: In my application an embedded device (no public IP) should connect to the GAE in order to obtain some data from it. The data are provided by the web browser. The whole data-passing process looks like: web browser - GAE - embedded standalone device I developed a servlet the device connects to. It issues the HTTP GET. On the other side the web browser sends data using standard GWT RemoteServiceServlet. In case there is no data for the device the doGet method in the servlet should stop for some seconds until user enters data or time out expires. I'm trying to use LinkedBlockingQueue to pass data between two servlets. It does not work unfortunately. Seems like the GAE launches new JVM for concurrent requests... I pushed the LinkedBlockingQueue into memcache and get it by name from concurrent requests. Still does not work. Memcache returns NOTnull. But there are no data in the queue. In order to investigate my issue I've made some tests with the semaphore. Pushed the semaphore to the memcache and made some concurrent operations ... - does not work - one process does not release the other... The problem occurs on GAE only. The whole mechanism works on the development server. Is there any way to stop/freeze one process (in the doGet method in servlet) and unblock it by another one ? Or... Is there any other way to solve my problem ? Thank you for any suggestions. Artur -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at
Re: [appengine-java] Re: Semaphores/ LinkedBlockingQueue on GAE for java
At the moment the Channel API is javascript only. There are a lot of people that would like it to be open to other languages for things just like you want to do. You might be able to use something like Rhino to run the javascript in Java but not sure if that will work. You should take a look at XMPP, it's very simple to have the server send instant messages. I did a quick search for XMPP libraries in Java and here is one I found. I'm sure there are many others. Check out http://twit88.com/blog/2009/02/17/java-xmpp-client-library/ On Sat, Jan 29, 2011 at 2:07 PM, Artur Downar artur.dow...@googlemail.comwrote: Thank you. I took a brief look on channel API and it seems I it is the thing I need. I have a small question. The modem device is a java embedded device and it has no public IP. There is no javascript on it. Only java. Is it enough for GAE channel API to communicate with it ? On Sat, Jan 29, 2011 at 9:49 PM, Stephen Johnson onepagewo...@gmail.com wrote: Sounds like you need more of a Push style. Checkout the Channel API or the XMPP api. On Sat, Jan 29, 2011 at 1:47 PM, Artur Downar artur.dow...@googlemail.com wrote: The external device polls for data from GAE. It is not specified when the data arrives. To describe it more clearly. The device is a GSM modem device that sends an SMS on the user request. The user launches a web browser and writes a mobile phone number. The browser sends data to the GAE and the sms should be send immediately So I cannot specify how long I can wait in Thread.sleep(). You mention about Objectify. I use that library but I'm quite new to it. Does it have the mechanism that works like: process A waits for data until data into database arrives or timeout expires process B puts the data into database process a continues processing the data inserted by process B ? On Sat, Jan 29, 2011 at 3:59 PM, Didier Durand durand.did...@gmail.comwrote: Hi, Forgot: you can use Thread.sleep() to wait (java.lang.Thread is also part of the JRE) regards didier On Jan 29, 3:35 pm, Didier Durand durand.did...@gmail.com wrote: Hi, LinkedBlokingQueue is part of JRE WhiteList: http://code.google.com/appengine/docs/java/jrewhitelist.html. So, you can use it. But, I dont see the need. Why don't you just from on the datastore on 1 side and read from it on the other. It would be very simple and rely on the most basic (i.e solid) mechanism of gae. (I would recommend Objectify for ds read/ write) As you have network round-trips, the read / write time will be negligible even it can seem high compared to an in-memory mechanism like a Queue. regards didier On Jan 29, 1:51 pm, arturad artur.dow...@googlemail.com wrote: In my application an embedded device (no public IP) should connect to the GAE in order to obtain some data from it. The data are provided by the web browser. The whole data-passing process looks like: web browser - GAE - embedded standalone device I developed a servlet the device connects to. It issues the HTTP GET. On the other side the web browser sends data using standard GWT RemoteServiceServlet. In case there is no data for the device the doGet method in the servlet should stop for some seconds until user enters data or time out expires. I'm trying to use LinkedBlockingQueue to pass data between two servlets. It does not work unfortunately. Seems like the GAE launches new JVM for concurrent requests... I pushed the LinkedBlockingQueue into memcache and get it by name from concurrent requests. Still does not work. Memcache returns NOTnull. But there are no data in the queue. In order to investigate my issue I've made some tests with the semaphore. Pushed the semaphore to the memcache and made some concurrent operations ... - does not work - one process does not release the other... The problem occurs on GAE only. The whole mechanism works on the development server. Is there any way to stop/freeze one process (in the doGet method in servlet) and unblock it by another one ? Or... Is there any other way to solve my problem ? Thank you for any suggestions. Artur -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from
[appengine-java] pass parameters through login service
I recently made it so most of my pages require a user to be logged in to view. The only problem I'm having is, if a user tries to come directly from a link myapp.appspot.com/page.jsp?pageId=aoSCuanjFAVoasDmNlkadf they are asked to login, then forwarded to myapp.appspot.com/page.jsp How do I make it so they are forwarded to myapp.appspot.com/page.jsp? pageId=aoSCuanjFAVoasDmNlkadf Is this possible? Should I not be showing users addresses like myapp.appspot.com/ page.jsp?pageId=aoSCuanjFAVoasDmNlkadf -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] pass parameters through login service
You should pick up any parameters passed to the page, send them to the login page, and then use that as the successURL for a successful login. -Ben Sent from my iPhone On Jan 29, 2011, at 5:06 PM, WillSpecht willspe...@gmail.com wrote: I recently made it so most of my pages require a user to be logged in to view. The only problem I'm having is, if a user tries to come directly from a link myapp.appspot.com/page.jsp?pageId=aoSCuanjFAVoasDmNlkadf they are asked to login, then forwarded to myapp.appspot.com/page.jsp How do I make it so they are forwarded to myapp.appspot.com/page.jsp? pageId=aoSCuanjFAVoasDmNlkadf Is this possible? Should I not be showing users addresses like myapp.appspot.com/ page.jsp?pageId=aoSCuanjFAVoasDmNlkadf -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: pass parameters through login service
I am using the Google authorization services with security- constraint. How do I specify the successURL. It seems to automatically pass the URL the user was trying to access before needing to log in, only it cuts off all the parameters. Do I need a filter of some kind that is run before each request and saves parameters? On Jan 29, 6:38 pm, Ben Carlson bencarl...@gmail.com wrote: You should pick up any parameters passed to the page, send them to the login page, and then use that as the successURL for a successful login. -Ben Sent from my iPhone On Jan 29, 2011, at 5:06 PM, WillSpecht willspe...@gmail.com wrote: I recently made it so most of my pages require a user to be logged in to view. The only problem I'm having is, if a user tries to come directly from a link myapp.appspot.com/page.jsp?pageId=aoSCuanjFAVoasDmNlkadf they are asked to login, then forwarded to myapp.appspot.com/page.jsp How do I make it so they are forwarded to myapp.appspot.com/page.jsp? pageId=aoSCuanjFAVoasDmNlkadf Is this possible? Should I not be showing users addresses like myapp.appspot.com/ page.jsp?pageId=aoSCuanjFAVoasDmNlkadf -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group athttp://groups.google.com/group/google-appengine-java?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
[appengine-java] Re: Semaphores/ LinkedBlockingQueue on GAE for java
Hi,
To answer your questions:
a) yes, you can say how long you waits Thread.sleep(millis) where
millis says how many milliseconds you want to wait
b) why don't you do something like this
do {
read new data from ds;
}
On Jan 29, 10:38 pm, Stephen Johnson onepagewo...@gmail.com wrote:
At the moment the Channel API is javascript only. There are a lot of people
that would like it to be open to other languages for things just like you
want to do. You might be able to use something like Rhino to run the
javascript in Java but not sure if that will work. You should take a look at
XMPP, it's very simple to have the server send instant messages. I did a
quick search for XMPP libraries in Java and here is one I found. I'm sure
there are many others. Check
outhttp://twit88.com/blog/2009/02/17/java-xmpp-client-library/
On Sat, Jan 29, 2011 at 2:07 PM, Artur Downar
artur.dow...@googlemail.comwrote:
Thank you.
I took a brief look on channel API and it seems I it is the thing I need.
I have a small question.
The modem device is a java embedded device and it has no public IP. There
is no javascript on it. Only java.
Is it enough for GAE channel API to communicate with it ?
On Sat, Jan 29, 2011 at 9:49 PM, Stephen Johnson onepagewo...@gmail.com
wrote:
Sounds like you need more of a Push style. Checkout the Channel API or the
XMPP api.
On Sat, Jan 29, 2011 at 1:47 PM, Artur Downar
artur.dow...@googlemail.com wrote:
The external device polls for data from GAE.
It is not specified when the data arrives. To describe it more clearly.
The device is a GSM modem device that sends an SMS on the user request.
The user launches a web browser and writes a mobile phone number. The
browser sends data to the GAE and the sms should be send immediately
So I cannot specify how long I can wait in Thread.sleep().
You mention about Objectify. I use that library but I'm quite new to it.
Does it have the mechanism that works like:
process A waits for data until data into database arrives or timeout
expires
process B puts the data into database
process a continues processing the data inserted by process B
?
On Sat, Jan 29, 2011 at 3:59 PM, Didier Durand
durand.did...@gmail.comwrote:
Hi,
Forgot: you can use Thread.sleep() to wait (java.lang.Thread is also
part of the JRE)
regards
didier
On Jan 29, 3:35 pm, Didier Durand durand.did...@gmail.com wrote:
Hi,
LinkedBlokingQueue is part of JRE WhiteList:
http://code.google.com/appengine/docs/java/jrewhitelist.html. So, you
can use it.
But, I dont see the need. Why don't you just from on the datastore on
1 side and read from it on the other. It would be very simple and rely
on the most basic (i.e solid) mechanism of gae. (I would recommend
Objectify for ds read/ write)
As you have network round-trips, the read / write time will be
negligible even it can seem high compared to an in-memory mechanism
like a Queue.
regards
didier
On Jan 29, 1:51 pm, arturad artur.dow...@googlemail.com wrote:
In my application an embedded device (no public IP) should connect
to
the GAE in order to obtain some data from it. The data are provided
by
the web browser.
The whole data-passing process looks like:
web browser - GAE -
embedded standalone device
I developed a servlet the device connects to. It issues the HTTP
GET.
On the other side the web browser sends data using standard GWT
RemoteServiceServlet.
In case there is no data for the device the doGet method in the
servlet should stop for some seconds until user enters data or time
out expires.
I'm trying to use LinkedBlockingQueue to pass data between two
servlets. It does not work unfortunately. Seems like the GAE
launches
new JVM for concurrent requests... I pushed the LinkedBlockingQueue
into memcache and get it by name from concurrent requests. Still
does
not work. Memcache returns NOTnull. But there are no data in the
queue.
In order to investigate my issue I've made some tests with the
semaphore. Pushed the semaphore to the memcache and made some
concurrent operations ... - does not work - one process does not
release the other...
The problem occurs on GAE only. The whole mechanism works on the
development server.
Is there any way to stop/freeze one process (in the doGet method in
servlet) and unblock it by another one ?
Or... Is there any other way to solve my problem ?
Thank you for any suggestions.
Artur
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[appengine-java] Re: Semaphores/ LinkedBlockingQueue on GAE for java
Sorry,
hit send too quicly
b) why don't you do something like this
Side reading data:
==
do {
read new data from ds;
if (new data) {
mark data as read in ds
do what you need
return;
} else {
Thread.sleep(100)
}
} until (running time near 30s)
if (no new data) {
give error message to waiting user
}
Side writing data
==
write new data to datastore (with corresponding status showing that
it's new and not read yet)
N.B: the 30s is a hard limit imposed by gae. You've to check for it
and end gracefully else your servlet will be killed by GAE.
regards
didier
On Jan 30, 8:15 am, Didier Durand durand.did...@gmail.com wrote:
Hi,
To answer your questions:
a) yes, you can say how long you waits Thread.sleep(millis) where
millis says how many milliseconds you want to wait
b) why don't you do something like this
do {
read new data from ds;
}
On Jan 29, 10:38 pm, Stephen Johnson onepagewo...@gmail.com wrote:
At the moment the Channel API is javascript only. There are a lot of people
that would like it to be open to other languages for things just like you
want to do. You might be able to use something like Rhino to run the
javascript in Java but not sure if that will work. You should take a look at
XMPP, it's very simple to have the server send instant messages. I did a
quick search for XMPP libraries in Java and here is one I found. I'm sure
there are many others. Check
outhttp://twit88.com/blog/2009/02/17/java-xmpp-client-library/
On Sat, Jan 29, 2011 at 2:07 PM, Artur Downar
artur.dow...@googlemail.comwrote:
Thank you.
I took a brief look on channel API and it seems I it is the thing I need.
I have a small question.
The modem device is a java embedded device and it has no public IP. There
is no javascript on it. Only java.
Is it enough for GAE channel API to communicate with it ?
On Sat, Jan 29, 2011 at 9:49 PM, Stephen Johnson onepagewo...@gmail.com
wrote:
Sounds like you need more of a Push style. Checkout the Channel API or
the
XMPP api.
On Sat, Jan 29, 2011 at 1:47 PM, Artur Downar
artur.dow...@googlemail.com wrote:
The external device polls for data from GAE.
It is not specified when the data arrives. To describe it more clearly.
The device is a GSM modem device that sends an SMS on the user request.
The user launches a web browser and writes a mobile phone number. The
browser sends data to the GAE and the sms should be send immediately
So I cannot specify how long I can wait in Thread.sleep().
You mention about Objectify. I use that library but I'm quite new to it.
Does it have the mechanism that works like:
process A waits for data until data into database arrives or timeout
expires
process B puts the data into database
process a continues processing the data inserted by process B
?
On Sat, Jan 29, 2011 at 3:59 PM, Didier Durand
durand.did...@gmail.comwrote:
Hi,
Forgot: you can use Thread.sleep() to wait (java.lang.Thread is also
part of the JRE)
regards
didier
On Jan 29, 3:35 pm, Didier Durand durand.did...@gmail.com wrote:
Hi,
LinkedBlokingQueue is part of JRE WhiteList:
http://code.google.com/appengine/docs/java/jrewhitelist.html. So, you
can use it.
But, I dont see the need. Why don't you just from on the datastore on
1 side and read from it on the other. It would be very simple and
rely
on the most basic (i.e solid) mechanism of gae. (I would recommend
Objectify for ds read/ write)
As you have network round-trips, the read / write time will be
negligible even it can seem high compared to an in-memory mechanism
like a Queue.
regards
didier
On Jan 29, 1:51 pm, arturad artur.dow...@googlemail.com wrote:
In my application an embedded device (no public IP) should connect
to
the GAE in order to obtain some data from it. The data are provided
by
the web browser.
The whole data-passing process looks like:
web browser - GAE -
embedded standalone device
I developed a servlet the device connects to. It issues the HTTP
GET.
On the other side the web browser sends data using standard GWT
RemoteServiceServlet.
In case there is no data for the device the doGet method in the
servlet should stop for some seconds until user enters data or time
out expires.
I'm trying to use LinkedBlockingQueue to pass data between two
servlets. It does not work unfortunately. Seems like the GAE
launches
new JVM for concurrent requests... I pushed the LinkedBlockingQueue
into memcache and get it by name from concurrent requests. Still
does
not work. Memcache returns NOTnull. But there are no data in the
queue.
In order to investigate my issue I've
[appengine-java] Re: Get execution duration of an asynchronous urlfetch
Hi, You're right: async url fetch doesn't seem to provide any way to measure fetch time. Then, I have a proposal: why don't you schedule a task per fetch, this task will then do a regular synchronous url fetch for which measuring will be easy. So, your original servlet / task will schedule as many tasks as you have fetches and wait via a loop of Thread.sleep() until all fetches are done and their results (incl fetch time) written somewhere (datastore / memcache) that the original servlet / task can access to complete the work. The only question though: can the application afford to launch those tasks as they will incurr some overhead : some tenths of milliseconds of cpu to schedule a task and run it + cpu time to write result to cacche or ds in order to be shareable with originator. If not acceptable, I hope it will at least give you some other ideas to follow regards didier On Jan 29, 9:50 am, Fabrizio Accatino fht...@gmail.com wrote: Hello, I'm playing with async urlfetch. My ispiration was Ikai athttp://ikaisays.com/2010/06/29/using-asynchronous-urlfetch-on-java-ap... I run some request in parallel. All works fine. But now I'd like to get info about execution time of each request. The target URLs I call are different so the response time are very different. I read the documentation but HTTPResponse does not expose a execution duration or similar value. Any idea? Fabrizio -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
