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2 Same HTTP Requests Give Different Results?

What differentiate these 2 requests that cause them to have different results/responses from the server although they should be the same ?
Request initiated by Chrome after a simple
click/navigation(successful, response code is 302)
I simply copied
that request as a curl and imported it to Postman and then postman
hanged
I did the same with Java - HttpUrlConnection(mimicking all the request headers and cookies like Chrome sent), but it hanged and waited forever. Is this simply because of the server logic that doesn't accept non-browser client ?
Here are the steps that I tried:
1. Visited this link: https://www.tokopedia.com/p/handphone-tablet/handphone
2. I opened the inspector and opened the Network - All tab
3. I clicked one of the products
4. I clicked the top request from the Network - All tab
5. I copied it as cURL bash
6. I imported it to Postman
7. I ran that request
8. Postman hanged

Actually the problem might even go deeper than what the other answers say.
So neither the User-Agent request header nor telnet might solve that problem (unless you initialize the TLS handshake also with telnet MANUALLY, but that is near impossible to complete).
TLS fingerprinting
If the connection is an SSL/TLS connection, the server could detect which algorithm is used to generate keys, and most applications have their specific signature / cipher.
So only by the TLS handshake alone you can tell Chrome from Postman or FireFox or Java. Java usually - unless a JVM implementation REALLY wants to go off-road - has the same signature across all platforms, using the same cipher/algorithm across all implementations.
I am sorry I cannot properly recall the name of this technique. The first project I know that published this is called something like "A3" or "S3". Salesforce published an article about JA3 analysis. They describe the technique and show a list of signatures and applications so you can guesstimate what app you're talking to, without the need to even decrypt the data: https://engineering.salesforce.com/tls-fingerprinting-with-ja3-and-ja3s-247362855967
My Solution
I had that same problem too, wanted to scan the NVidia or AMD servers for graphics card availability. Did not work from Java, so after a lot of research, finding the project mentioned above, I simply used Selenium to control FireFox and that got the proper server responses and I achieved my goal this way.

The only way to be sure that the exact same data is sent is to manually send it yourself through something like telnet. I had a similar problem once- it turned out that the browser was sending the data in one big chunk, while my code was sending it line-by-line. No site should have this problem, but it's possible that it exists.

The server might be checking for User-Agent request header and will block traffic that does not originate from a browser. Try setting the header in curl or your Java Code to a value corresponding to (any) browser. I've encountered such behavior on some e-shops and commercial websites.

Android Volley error while posting data to server

here is the api response which works fine While posting data to the server I'm getting server volley error as response code but at the same time remaining API working fine.

HTTP 404 ordinary means "page not found" ...
host-name mydrivinglession.co.uk cannot even be resolved in DNS:
$ traceroute mydrivinglession.co.uk
mydrivinglession.co.uk: Name or service not known
... nor is it registered with co.uk
mydrivinglession.co.uk is available!
guess you would have to remove mydrivinglession.co.uk from your local hosts file... that most likely the only reason why the response, which you claim would be "working", appears to be "working".
one might want to establish a publicly available API, before attempting to perform requests... because your requests might run against a fantasy domain in the clouds, which nobody knows.

Always getting error “Non HTTP response code: java.net.UnknownHostException”

I tried stress testing with JMeter software to test a web site as it crashed after a sms campaign. Currently site has been moved to a physical server.
I tested multiple times by adding threads, it worked and gave few errors (for above 1000 threads), and worked for 400 threads with no error. So I tried distributed testing with 4 PCs including my one.
After I tried again with only my PC to send requests to the site by adding 400 threads(ramp up = 1 , loop = 1). But each and every requests gives error. Then I tried using 1 thread. Same error was given.
I checked my network connection, and there is no problem. Then I browsed the web site "http://www.myjobs.lk/", and it works fine.
These are the values I have given in testing.
Under this condition, I cannot perform the testing because it always gives errors. How can I overcome this problem?

You're using incorrect JMeter configuration, change it as follows:
Remove http:// from "Server Name or IP" input
Put http to "Protocol input
It is also possible to have the full URL in "Path" field like
But using "http://" in "Server Name or IP" won't work.
Also once you defined hostname, port, path, etc. in HTTP Request Defaults it will be automatically applied to all HTTP Request Samplers. You will be able to override an option for particular this or that sampler but if you don't - default value will be used. See Why It's SO Important To Use JMeter's HTTP Request Defaults for more detailed explanation and some use cases.

For me it was helpful to setup proxy server:

Looks like JMeter tries to connect to myjobs.lk, and you browse to www.myjobs.lk. Try changing so that JMeter also connects to www.myjobs.lk

play framework receive paypal IPN request

I tried to send an IPN (from the simulator) to my play framework url!
the url looks like that: http://host/checkout/sub
Server is running on port 80. The problem is that the ipn request doesn't even call the linked method. (So the method that i just defined in the routes is never called, if I request an ipn), but still there is an incoming request!
If i try to call the URL via browser, I don’t experience any problems and the method is called properly.
So did anyone else face that problem?
Should I try another way?
Help is very appreciated!
Kind Regards,
Paul
Edit: I get that exception after about 5 minutes
[error] p.nettyException - Exception caught in Netty
java.lang.IllegalArgumentException: empty text at org.jboss.netty.handler.codec.http.HttpVersion.(HttpVersion.java:97) ~[netty-3.9.8.Final.jar:na]

Finally...
1) I had to fix some settings at my service provider (Open Internet -> yes)
2) I had to change the port to 80 (was on 9000 for testing)
3) The exceptions by play and paypal didnt really say anything... wireshark did, once again, a good job: in my routes files i defined the rout as GET but of course they are sending their data via POST (stupid mistake :P)
Kind regards

400 Http Errors Using Jsoup in Multithreaded Program

I've created a program that parses html pages. I use jsoup connect function within a callable class inside ThreadPool. The problem is that I'm connecting to the same website and with a thread pool size of 5+, I get IO Exceptions - 400 errors.
How do I not make that happen?

If you're getting a 400 HTTP response, check the content of the response for an error message. A 400 means a bad request of some kind: you didn't include all the required information or included malformed information. Some people also use it as kind of a catch-all for when the client did something they don't like. If you're making lots of different requests, examine the ones that caused 400's to see if there's something wrong with them. If they all look right or if you're sending the same requests repeatedly, then maybe the site you're hitting has some kind of rate limiting that disallows you from making too many concurrent requests or too many requests within a particular timeframe. If it's something like that, I'd expect there to be a message in the response telling you what's going on.