I'm looking for any way to run PUT and DELETE methods for Java Servlets. In general, I have a simple application with web control (WAR) connected with EJB project that controls a simple list of libraries. For each of CRUD actions I would like to use different different method:
However create I make by simple form with post method, read (list) is executed by simple entering GET in the URL address (without form), but I have no idea how could I use put and delete for their purposes.
Unfortunately online resources I found didn't answer that question, but I'm just curious how I could use id.
I assume removing by e.g. /Servlet/:libraryId (without any body), update by the same URL schema (with updated schema). doPut() and doDelete() should just run proper actions in the EJB.
There's no way on the HTML level to create a DELETE request in a form submit (it's always GET or POST, except you start to write your own browser that handles the kind of non standard HTML you proposed), all you can do is to submit a value (taken from a hidden field, radio button, whatever) that expresses which action should be taken in the doPost() or doGet() handler on the server.
But then there's nothing special about DELETE on the http protocol level. The whole request is just a sequence of bytes, where the first few define the method (PUT, GET, DELETE, PATCH...), followed by space etc.
As far as your server is concerned you could even use web sockets to accept connections and create responses to self defined fantasy methods. If you're using servlets, you have doPut(), doGet() and doDelete() available anyway. To handle other http methods you'd have to override the service() method.
On the client side Angular's HttpClient allows for all three methods that you need, you could use jquery's ajax, or there's again the web socket approach on the client too, as long as the browser plays along.
If it is a Java client, again there are web sockets (but you'd want to send some valid http request instead of "Hello", as done in the example¹.), HttpUrlConnection and the Apache HttpClient, at a first glance.
As for testing, there are browser extensions available that let you compose requests other than PUT and GET, SoapUi as a tool is very popular, IntelliJ even has a http client, that allows you to type the complete request as plain text.
¹ If you have a hand crafted server that agrees to such a "Hello" protocol, that's fine too. Its just not http.
Since there was quite some confusion in the question, as it turned out, I'd like to promote the idea some more to write your own Http client/server with webSockts. You have ready made examples for the socket stuff, so that's easy.
But it's more interesting then, that you're at the raw tcp/ip level that http is built on, all this framework-redirection (servlets, whatever) drops away and you're left with a single text basically (well, a byte stream), that's the http request. All the magic is gone, things are obvious and simple, just as specified.