That's one way to do this, on Spring side
@PostMapping("api/user")
public Response theAction(@RequestBody List<User> users)on the javascript side,
      let data = JSON.stringify([{name: 'dddddd'}, {name: 'bbbbb'}]);
      axios.post("/user/update/social-accounts", data, {
          headers: {
            "Content-Type": "application/json", // very important
          },
        })
        .then(function (response) {
          console.log(response);
        })
        .catch(function (error) {
          console.log(error);
        });