hcarrasko's questions

I have a question regarding these three data transmission protocols on the Internet. I know that TCP/IP sockets are a form of low-level communication that uses the transport layer to perform data transmission and handles it very well.

But the WebSockets and the HTTP Request , I understand that they are built on the application layer and from the examples that I have seen both are very similar in terms of their form.

I am right? Are WebSockets an enhancement to HTTP Request or are they the same thing? In what cases is it better to use WebSockets than an HTTP Request?

I am working on a client-server application which communicates over the TCP/IP protocol, where I sporadically get the error connection reset by peer.

By "connection reset " I mean that the connection has been reset? Or does this mean that the client system has been disconnected from the server and communication between the two is not possible?

I would like to modify the message of a particular commit, I know that with the following command I can modify the message of the last commit made:

git commit --amend -m "your new message"

But how can I modify the message of the penultimate commit made? It's possible?

What is the difference between HashMapand Hashtable? According to what I know about data structures, it would be the same conceptually, but in Java , what would be the difference?

Which is more recommended to be used in applications that use Threads?

I am trying to get the screen dimensions of an Android device, I am trying with this code:

Display display = getWindowManager().getDefaultDisplay(); 
int width = display.getWidth();  // obsoleto (deprecated)
int height = display.getHeight();  // obsoleto (deprecated)

Which is obsolete (deprecated), what would be the current correct way to obtain the dimensions of the device screen?

I am trying to generate random numbers in Java within a given range with the following code:

int randomNum = rand.nextInt((max - min) + 1) + min;

But this only generates numbers for me in the set of integers. How can I get numbers that are also decimals?