As such, I am developing a web application with spring boot and I can not find a way to return the result of a jpa query in json format using an ajax request. If I create an instance of one of my entities and return it in the controller with @ResponseBody it works perfectly but if I return an ArrayList or that same instance being the result of a query in the repository Spring tool suite hangs.
You could use the library JSONObject that comes in primefaces that is very easy to use I leave you an example:
JSONObject body = new JSONObject();
body.put("identificador", Integer.parseInt(empleadoAccion.getIdentificador()));
body.put("accion", "bloquear");
body.put("url", sesion.getSesion().getRequestUri());
body.put("ip", sesion.getSesion().getIp())
if you use maven then you can add it to the pom in this way
<dependency>
<groupId>org.primefaces</groupId>
<artifactId>primefaces</artifactId>
<version>5.3</version>
<type>jar</type>
</dependency>
Or you can download the library here