#GetMapping method not calles - spring-boot

Question

I am a beginner so please don't be mean.
I have got an html page index.html
And I want the method MainController::getListEmployee to be called.
In this method, I put a System.err to see if the method is called. And I see nothing.
Controller code
package com.cgi.listeemployes.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import com.cgi.listeemployes.model.User;
import com.cgi.listeemployes.repository.UserRepository;
#Controller // This means that this class is a Controller
#RequestMapping(path="/") // This means URL's start with /demo (after Application path)
public class MainController {
#Autowired // This means to get the bean called userRepository
// Which is auto-generated by Spring, we will use it to handle the data
private UserRepository userRepository;
#GetMapping(path="/index.html")
public #ResponseBody Iterable<User> getListEmployee() {
// This returns a JSON or XML with the users
System.err.println("getting ");
return userRepository.findAll();
}
#PostMapping(path="/add") // Map ONLY POST Requests
public #ResponseBody String addNewUser (#RequestParam String name
, #RequestParam String email) {
// #ResponseBody means the returned String is the response, not a view name
// #RequestParam means it is a parameter from the GET or POST request
User n = new User();
n.setName(name);
n.setEmail(email);
userRepository.save(n);
return "Saved";
}
#GetMapping(path="/all")
public #ResponseBody Iterable<User> getAllUsers() {
// This returns a JSON or XML with the users
return userRepository.findAll();
}
}
thanks for your help

Answer 1

When you want to return a html, just return a string with the name of the html file, it could be "Index" (without the .html).
In your #GetMapping(path="/index.html"), you are returning an object instead a html.
If you want to load data from database and render it at your html, then add the attribute "Model model" in your parameters, like this:
#GetMapping(path="/index.html")
public String getListEmployee(Model model) {
List<User> users = userRepository.findAll();
model.addAttribute("yourUsers", users); // this gonna inject the list of users in your html
System.err.println("getting ");
return "Index"
}
Then in your html, you can get the users with ${yourUsers} and do whatever you want.
I saw your project, it is missing the template engine. Template engine is what gonna get the data of your backend and show in your front/html. I added the Thymeleaf template engine into your pom.xml, and it worked. Here is the thymeleaf dependency:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
To work with thymeleaf, you have to put all your html into a new folder called "templates" in the "resources", same level of "static". You cannot use html in the static folder, this folder should have only css, javascripts and assets.