Function fecth: The CORS header 'Access-Control-Allow-Origin' is not present

Question

I am trying to simulate an application I am running on a local Glassfish server. The IDE I am using is: Intellij. I built a method that consumes an API service from an address:

http://localhost:8080/<BACKEND>/rest/home/listar

I’m trying to consume through the address:

http://localhost:3002/

This is the error generated in the browser:

Blocked cross-origin request: Same origin policy (Same Origin Policy) prevents reading the remote resource on http://localhost:8080//Rest/home/listar. (Reason: CORS header 'Access-Control-Allow-Origin' is not present). Networkerror when attempting to fetch Resource.

The algorithm I used in my frontend application was:

Homecontroller.ts

importaLista() {

        function isOk(res : any) {
            if (res.ok) return res;
            else throw new Error(res.statusText);
        }

        fetch('http://localhost:8080/corujito.com-1.0-SNAPSHOT/rest/home/listar')
            .then(res => isOk(res))
            .then(res => res.json())
            .then(
                (dados:any[]) => {
                    dados.map(dado => new Ensaio(dado))
                    .forEach(ensaio => this._ensaios.adiciona(ensaio))

                }
            ).catch(
                err => console.log(err.message)
            );
    }

Ensaiodao.ts

import { Ensaio } from "../models/Ensaio";

export class EnsaioDao {

    private _listas: Ensaio[] = [];

    adiciona(negociacao: Ensaio): void {
        this._listas.push(negociacao);
    }

    paraArray(): Ensaio[] {
        return ([] as Ensaio[]).concat(this._listas);
    }

    paraTexto(): void {
        console.log('Impressão');
        console.log(JSON.stringify(this._listas));
    }

}

app ts.

import { HomeController } from "./controllers/HomeController";

const homeController = new HomeController();

homeController.importaLista();
console.log(homeController.getList());