br.ufsc.inf.ine5646.rest.CalculadoraServlet.java Source code

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Here is the source code for br.ufsc.inf.ine5646.rest.CalculadoraServlet.java

Source

/*
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package br.ufsc.inf.ine5646.rest;

import com.google.gson.JsonArray;
import com.google.gson.JsonElement;
import com.google.gson.JsonPrimitive;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 *
 * @author diego
 */
@WebServlet(name = "CalculadoraServlet", urlPatterns = { "/calc/*" })
public class CalculadoraServlet extends HttpServlet {

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("application/json;charset=UTF-8");
        try (PrintWriter out = resp.getWriter()) {
            out.println(handleRequest(req.getPathInfo().substring(1)));
        }

    }

    public String handleRequest(String urlParams) {
        String[] params = urlParams.split("/");
        JsonArray ja = new JsonArray();
        try {
            if (params.length != 3) {
                ja.add(new JsonPrimitive("erro"));
                ja.add(new JsonPrimitive("nmero de parmetros incorreto! Exemplo: soma/5/8"));
            } else if (!params[0].equals("soma") && !params[0].equals("subt") && !params[0].equals("mult")
                    && !params[0].equals("divi")) {
                ja.add(new JsonPrimitive("erro"));
                ja.add(new JsonPrimitive("Operao deve ser uma destas: soma,subt,mult,divi"));
            } else if (params[0].equals("divi") && Double.parseDouble(params[2]) == 0) {
                ja.add(new JsonPrimitive("erro"));
                ja.add(new JsonPrimitive("diviso por zero"));
            } else {
                double num1 = Double.parseDouble(params[1]);
                double num2 = Double.parseDouble(params[2]);

                ja.add(new JsonPrimitive("ok"));

                switch (params[0]) {
                case "soma":
                    ja.add(new JsonPrimitive(num1 + num2));
                    break;
                case "subt":
                    ja.add(new JsonPrimitive(num1 - num2));
                    break;
                case "mult":
                    ja.add(new JsonPrimitive(num1 * num2));
                    break;
                case "divi":
                    ja.add(new JsonPrimitive(num1 / num2));
                    break;
                default:
                    break;
                }
            }

        } catch (NumberFormatException ex) {
            ja.add(new JsonPrimitive("erro"));
            ja.add(new JsonPrimitive(params[1] + " e/ou " + params[2] + " no  nmero"));
        }

        return ja.toString();
    }

}