java/w10/ArticleRepository.java

package com.rental.crawler.repository;

import com.rental.crawler.model.Book;
import java.util.ArrayList;
import java.util.List;

public class ArticleRepository {
    private List<Book> articles;

    public ArticleRepository() {
        this.articles = new ArrayList<>();
    }

    public ArticleRepository(List<Book> articles) {
        this.articles = articles != null ? new ArrayList<>(articles) : new ArrayList<>();
    }

    public void add(Book article) {
        if (article != null) {
            this.articles.add(article);
        }
    }

    public void addAll(List<Book> newArticles) {
        if (newArticles == null) {
            return;
        }
        for (Book article : newArticles) {
            if (article != null) {
                this.articles.add(article);
            }
        }
    }

    public List<Book> findAll() {
        return new ArrayList<>(this.articles);
    }

    public Book findByIndex(int index) {
        if (index >= 0 && index < this.articles.size()) {
            return this.articles.get(index);
        }
        return null;
    }

    public int size() {
        return this.articles.size();
    }

    public void clear() {
        this.articles.clear();
    }

    public boolean isEmpty() {
        return this.articles.isEmpty();
    }
}