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Testing HLS using JMeter

I am using JMeter to test HLS playback from a Streaming Server. So, the first HTTP request is for a master manifest file(m3u8). Say,
http://myserver/application1/subpath1/file1.m3u8
The reply to this will result in a playlist something like,
subsubFolder/360p/file1.m3u8
subsubFolder/480p/file1.m3u8
subsubFolder/720p/file1.m3u8
So, next set of URLs become
http://myserver/application1/subpath1/subsubFolder/360p/file1.m3u8
http://myserver/application1/subpath1/subsubFolder/480p/file1.m3u8
http://myserver/application1/subpath1/subsubFolder/720p/file1.m3u8
Now, individual reply to these further will be an index of chunks, like
0/file1.ts
1/file1.ts
2/file2.ts
3/file3.ts
Again, we have next set of URLs as
http://myserver/application1/subpath1/subsubFolder/360p/0/file1.ts
http://myserver/application1/subpath1/subsubFolder/360p/1/file1.ts
http://myserver/application1/subpath1/subsubFolder/360p/2/file1.ts
http://myserver/application1/subpath1/subsubFolder/360p/3/file1.ts
This is just the case of one set(360p). There will be 2 more sets like these(for 480p, 720p).
I hope the requirement statement is clear uptill this.
Now, the problem statement.
Using http://myserver/application1 as static part, regex(.+?).m3u8 is applied at 1st reply which gives subpath1/subsubFolder/360p/file1. This, is then added to the static part again, to get http://myserver/application1/subpath1/subsubFolder/360p/file1 + .m3u8
The problem comes at the next stage. As, you can see, with parts extracted previously, all I'm getting is
http://myserver/application1/subpath1/subsubFolder/360p/file1/0/file1.ts
The problem is obvious, an extra file1, 360p/file1 in place of 360p/0.
Any suggestions, inputs or alternate approaches appreciated.

If I understood the problem correctly, all you need is the file name as the other URLs can be constructed with it. Rather than using http://myserver/application1 as static part of your regex, I would try to get the filename directly:
([^\/.]+)\.m3u8$
# match one or more characters that are not a forward slash or a period
# followed by a period
# followed by the file extension (m3u8)
# anchor the whole match to the end
Now consider your urls, e.g. http://myserver/application1/subpath1/subsubFolder/360p/file1.m3u8, the above regex will capture file1, see a working demo here. Now you can construct the other URLs, e.g. (pseudo code):
http://myserver/application1/subpath1/subsubFolder/360p/ + filename + .m3u8
http://myserver/application1/subpath1/subsubFolder/360p/ + filename + /0/ + filename + .ts
Is this what you were after?

Make sure you use:
(.*?) - as Regular Expression (change plus to asterisk in your regex)
-1 - as Match No.
$1$- as template
See How to Load Test HTTP Live Media Streaming (HLS) with JMeter article for detailed instructions.

If you are ready to pay for a commercial plugin, then there is an easy and much more realistic solution which is a plugin for Apache JMeter provided by UbikLoadPack:
Besides doing this job for you, it will simulate the way a player would read the file. It will also scale much better than any custom script or player solution.
It supports VOD and Live which are quite difficult to script.
See:
http://www.ubik-ingenierie.com/blog/easy-and-realistic-load-testing-of-http-live-streaming-hls-with-apache-jmeter/
http://www.ubik-ingenierie.com/blog/ubikloadpack-http-live-streaming-plugin-jmeter-videostreaming-mpegdash/
Disclaimer, we are the providers of this solution

GStreamer-Java: RTSP-Source to UDP-Sink

I'm currently working on a project to forward (and later transcode) a RTP-Stream from a IP-Webcam to a SIP-User in a videocall.
I came up with the following gstreamer pipeline:
gst-launch -v rtspsrc location="rtsp://user:pw#ip:554/axis-media/media.amp?videocodec=h264" ! rtph264depay ! rtph264pay ! udpsink sync=false host=xxx.xxx.xx.xx port=xxxx
It works very fine. Now I want to create this pipeline using java. This is my code for creating the pipe:
Pipeline pipe = new Pipeline("IPCamStream");
// Source
Element source = ElementFactory.make("rtspsrc", "source");
source.set("location", ipcam);
//Elements
Element rtpdepay = ElementFactory.make("rtph264depay", "rtpdepay");
Element rtppay = ElementFactory.make("rtph264pay", "rtppay");
//Sink
Element udpsink = ElementFactory.make("udpsink", "udpsink");
udpsink.set("sync", "false");
udpsink.set("host", sinkurl);
udpsink.set("port", sinkport);
//Connect
pipe.addMany(source, rtpdepay, rtppay, udpsink);
Element.linkMany(source, rtpdepay, rtppay, udpsink);
return pipe;
When I start/set up the pipeline, I'm able to see the input of the camera using wireshark, but unfortunately there is no sending to the UDP-Sink. I have checked the code for mistakes a couple of times, I even set a pipeline for streaming from a file (filesrc) to the same udpsink, and it also works fine.
But why is the "forwarding" of the IP-Cam to the UDP-Sink not working with this Java-Pipeline?

I haven't used the Java version of GStreamer, but something you need to be aware of when linking is that sometimes the source pad of an element is not immediately available.
If you do gst-inspect rtspsrc, and look at the pads, you'll see this:
Pad Templates:
SRC template: 'stream_%u'
Availability: Sometimes
Capabilities:
application/x-rtp
application/x-rdt
That "Availability: Sometimes" means your initial link will fail. The source pad you want will only appear after some number of RTP packets have arrived.
For this case you need to either link the elements manually by waiting for the pad-added event, or what I like to do in C is use the gst_parse_bin_from_description function. There is probably something similar in Java. It automatically adds listeners for the pad-added events and links up the pipeline.
gst-launch uses these same parse_bin functions, I believe. That's why it always links things up fine.

listen for "open file with my java application" event on windows

Title is confusing, but don't know how to explain this in a few words:
I have a java application that reads *.example files. I've also added a file association thanks to install4j so my application is launched when the user double clicks any file with extension *.example
It seems that install4j sends the file path in the args[] so it should be easy to open that file and show it in my app. BUT what happens if the app is already running? I can only allow one instance of the application so, how can I know that the user is opening a file?
I've found this: http://resources.ej-technologies.com/install4j/help/api/com/install4j/api/launcher/StartupNotification.html
But I still don't understand how should I use it and what should I add in my app to listen for this event. Where can I find an example?

Based on the documentation you linked to, it looks like you can do this:
StartupNotification.registerStartupListener(new StartupNotification.Listener() {
public void startupPerformed(String parameters) {
System.out.println("Startup performed with parameters " + parameters);
}
});
Since startupPerformed will be called from different threads, you will need to make sure that the code that handles these notifications is thread-safe.
The documentation also says:
For multiple files, files are surrounded by double-quotes and separated by spaces.
So you will need to parse the parameter string yourself as well.

Is it possible for a column to become a hyperlink using google charts API?

I am using Visualr http://googlevisualr.herokuapp.com/ with Rails and having a good amount of success creating dynamic charts. However, I am wondering if it's possible to allow the user to click on the column in a 'column chart' and be linked to a page? I am happy to know the java version if you aren't familiar with visualr.
Thanks!

It now is available!
There has recently been an update on this issue. Therefore I want to update this SO Q&A.
Resources:
Google Visualr Github Pull Request #39
Google Visualr Github Issue #36
Code example
xxx_controller.rb
#table = GoogleVisualr::Interactive::ColumnChart.new(g, options_g)
#table.add_listener("select", "function(e) {
EventHandler(e, chart, data_table)
}")
And then in a JS file e.g. app/assets/javascripts/application.js:
function EventHandler(e, chart, data) {
var selection = chart.getSelection();
if (selection.length > 0) {
var row = selection[0].row;
var department = data.getValue(row, 0);
alert(department + " | " + row)
}
}

Google Charts (whether you access them directly or via a wrapper gem like Visualr) are simple images, so the straight answer is "No", at least not without doing some work of your own. In order to achieve this you would need to place your own transparent clickable links (or divs or whatever) over the image, in the right place, to correspond to the columns that google generate in the image.
I'd imagine this would be tricky and error prone - it might actually be easier for you to just generate the columns yourself in html and css, using the data you would previously have sent to google to set the height (in %) of the columns. Then, each column would be a seperate html element and could link to whatever you want.
So, more control = more work. As usual :)

How do I overwrite the URL in an IE address bar using RFT?

I need to execute the following steps:
1. Start an IE browser window and open a URL (Done using StartBrowser(final string URL)
2. Start a session (done by logging in)
3. Now, I want to enter a different URL in the same browser window which has the same session.
My question is related to Step 3. How can I overwrite the URL in the existing IE window.
Note: I am using a keyword driven framework written in java.

From the IBM RFT online help: You can use the loadURL() method of the browser object.
If you do not have the browser object already 'learned' into your object map, just record a click on the browser toolbar. Then you can modify that line to be Browser_htmlBrowser().loadURL("http://stackoverflow.com");

Thanks Tom. I agree that loadURL has the implementation to do what I need.
There is one more aspect that may interest others looking at this question, i.e. the way the appropriate browser object is captured. Obviously the easist way is to use the RFT record and click way, and use the appropriate recognition properties or the other way is to implement it is find the existing browseron the fly when the method is called irrespective of recognistion properties etc which may be more useful for some scenarios or frameworks, like it is done below.
RootTestObject root = getRootTestObject();
TestObject[] testobj = root.find(atDescendant(".class", "Html.HtmlBrowser"));
BrowserTestObject bto;
bto = new BrowserTestObject(testobj[0]);
bto.loadUrl(curParamOne);