src/main/java/com/organization/servlet/MainServlet.java - master - itokar98/HomeWorkJSPRServlets

src/main/java/com/organization/servlet/MainServlet.java
82 строки3 KB
Ilya Tokar
first_commit
14 янв 2026, 01:32
14 янв 2026, 01:32a683d55
package com.organization.servlet;

import com.organization.controller.PostController;
import com.organization.repository.PostRepository;
import com.organization.service.PostService;

import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

public class MainServlet extends HttpServlet {
    private static final String API_POSTS = "/api/posts";
    private static final String GET = "GET";
    private static final String POST = "POST";
    private static final String DELETE = "DELETE";
    private static final String ID_PATH_REGEX = "/api/posts/\\d+";

    private PostController controller;

    @Override
    public void init() {
        final var repository = new PostRepository();
        final var service = new PostService(repository);
        controller = new PostController(service);
    }

    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) {
        try {
            final var path = req.getRequestURI();
            final var method = req.getMethod();

            if (GET.equals(method) && API_POSTS.equals(path)) {
                controller.all(resp);
                return;
            }
            if (GET.equals(method) && path.matches(ID_PATH_REGEX)) {
                handleIdRequest(path, controller::getById, resp);
                return;
            }
            if (POST.equals(method) && API_POSTS.equals(path)) {
                controller.save(req.getReader(), resp);
                return;
            }
            if (DELETE.equals(method) && path.matches(ID_PATH_REGEX)) {
                handleIdRequest(path, controller::removeById, resp);
                return;
            }
            resp.setStatus(HttpServletResponse.SC_NOT_FOUND);
        } catch (NumberFormatException e) {
            sendError(resp, HttpServletResponse.SC_BAD_REQUEST, "Invalid ID format");
        } catch (Exception e) {
            e.printStackTrace();
            resp.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
        }
    }

    private void handleIdRequest(String path, IdHandler handler, HttpServletResponse resp) throws IOException {
        final var id = extractId(path);
        handler.handle(id, resp);
    }

    private long extractId(String path) {
        return Long.parseLong(path.substring(path.lastIndexOf("/") + 1));
    }

    private void sendError(HttpServletResponse resp, int status, String message) {
        try {
            resp.setStatus(status);
            resp.setContentType("application/json");
            resp.setCharacterEncoding("UTF-8");
            resp.getWriter().write(String.format("{\"error\": \"%s\"}", message));
        } catch (IOException ignored) {
        }
    }

    @FunctionalInterface
    private interface IdHandler {
        void handle(long id, HttpServletResponse response) throws IOException;
    }
}