Merge pull request mouredev#7365 from danhingar/ejercicio26

#26 - Java

Roadmap/26 - SOLID SRP/java/danhingar.java

@@ -0,0 +1,310 @@
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+
+public class danhingar {
+
+    // Incorrecto
+    public class User {
+
+        private String name;
+        private String email;
+
+        public User(String name, String email) {
+            this.email = email;
+            this.name = name;
+        }
+
+        public void save(User user) {
+
+        }
+
+        public void sendEmail(User user) {
+
+        }
+
+    }
+
+    // Correcto
+    public class User1 {
+
+        private String name;
+        private String email;
+
+        public User1(String name, String email) {
+            this.name = name;
+            this.email = email;
+        }
+
+    }
+
+    public class UserService {
+
+        public void save(User1 user1) {
+
+        }
+
+    }
+
+    public class EmailService {
+
+        public void sendEmail(String email, String message) {
+
+        }
+    }
+
+    public static void main(String[] args) {
+        // WITHOUT SRP
+        Library library = new Library();
+        library.addUser(1, "Daniel", "[email protected]");
+        library.addUser(2, "Pepe", "[email protected]");
+        System.out.println(library.toString());
+        library.addBook("Libro 1", "Autor 1", 5);
+        library.addBook("Libro 2", "Autor 2", 3);
+        System.out.println(library.toString());
+        library.loanBook(1, "Libro 1");
+        library.loanBook(2, "Libro 1");
+        System.out.println(library.toString());
+        library.returnBook(2, "Libro 1");
+        System.out.println(library.toString());
+
+        // WITH SRP
+        Library2 library2 = new Library2();
+        library2.addUser(new User2(1, "Daniel", "[email protected]"));
+        library2.addUser(new User2(2, "Pepe", "[email protected]"));
+        System.out.println(library2.toString());
+        library2.addBook(new Book("Libro 1", "Autor 1", 5));
+        library2.addBook(new Book("Libro 2", "Autor 2", 3));
+        System.out.println(library2.toString());
+        library2.loanBook(1, "Libro 1");
+        library2.loanBook(2, "Libro 1");
+        System.out.println(library2.toString());
+        library2.returnBook(2, "Libro 1");
+        System.out.println(library2.toString());
+    }
+
+}
+
+// Extra
+
+// Incorrecto
+
+class Library {
+    private List<Map<String, Object>> users;
+    private List<Map<String, Object>> books;
+    private Map<Integer, List<String>> loans;
+
+    public Library() {
+        this.users = new ArrayList<>();
+        this.books = new ArrayList<>();
+        this.loans = new HashMap<>();
+    }
+
+    public void addBook(String title, String author, Integer copies) {
+        Map<String, Object> book = new HashMap<>();
+        book.put("title", title);
+        book.put("author", author);
+        book.put("copies", copies);
+        books.add(book);
+    }
+
+    public void addUser(Integer id, String name, String email) {
+        Map<String, Object> user = new HashMap<>();
+        user.put("id", id);
+        user.put("name", name);
+        user.put("email", email);
+        users.add(user);
+    }
+
+    public void loanBook(Integer userId, String bookTitle) {
+        for (Map<String, Object> book : books) {
+            if (book.get("title").equals(bookTitle) && (Integer) book.get("copies") > 0) {
+                book.put("copies", (Integer) book.get("copies") - 1);
+                List<String> booksUser = loans.get(userId) != null ? loans.get(userId) : new ArrayList<>();
+                booksUser.add(bookTitle);
+                loans.put(userId, booksUser);
+            }
+        }
+    }
+
+    public void returnBook(Integer userId, String bookTitle) {
+        boolean exist = this.loans.get(userId).stream().anyMatch(b -> b.equals(bookTitle));
+        if (exist) {
+            this.books.stream().filter(b -> b.get("title").equals(bookTitle))
+                    .forEach(b -> b.put("copies", (Integer) b.get("copies") + 1));
+            this.loans.get(userId).remove(bookTitle);
+        }
+    }
+
+    @Override
+    public String toString() {
+        return "Library [users=" + users.toString() + ", books=" + books.toString() + ", loans=" + loans.toString() + "]";
+    }
+}
+
+// Correcto
+
+class Library2 {
+
+    private List<User2> users;
+    private List<Book> books;
+    private Loan loans;
+
+    public Library2() {
+        users = new ArrayList<>();
+        books = new ArrayList<>();
+        loans = new Loan();
+    }
+
+    public void addBook(Book book) {
+        books.add(book);
+    }
+
+    public void addUser(User2 user) {
+        users.add(user);
+    }
+
+    public void loanBook(Integer userId, String bookTitle) {
+        Optional<User2> user = users.stream().filter(u -> u.getId().equals(userId)).findFirst();
+        Optional<Book> book = books.stream().filter(b -> b.getTitle().equals(bookTitle)).findFirst();
+        if (user.isPresent() && book.isPresent()) {
+            loans.loanBook(user.get(), book.get());
+        }
+
+    }
+
+    public void returnBook(Integer userId, String bookTitle) {
+        Optional<User2> user = users.stream().filter(u -> u.getId().equals(userId)).findFirst();
+        Optional<Book> book = books.stream().filter(b -> b.getTitle().equals(bookTitle)).findFirst();
+        if (user.isPresent() && book.isPresent()) {
+            loans.returnBook(user.get(), book.get());
+        }
+    }
+
+    @Override
+    public String toString() {
+        return "Library [users=" + users + ", books=" + books.toString() + ", loans=" + loans + "]";
+    }
+
+}
+
+class Book {
+
+    private String author;
+    private String title;
+    private Integer copies;
+
+    public Book(String title, String author, Integer copies) {
+        this.title = title;
+        this.author = author;
+        this.copies = copies;
+    }
+
+    public String getAuthor() {
+        return author;
+    }
+
+    public void setAuthor(String author) {
+        this.author = author;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public Integer getCopies() {
+        return copies;
+    }
+
+    public void setCopies(Integer copies) {
+        this.copies = copies;
+    }
+
+    @Override
+    public String toString() {
+        return "Book [author=" + author + ", title=" + title + ", copies=" + copies + "]";
+    }
+
+}
+
+class User2 {
+    private String name;
+    private Integer id;
+    private String email;
+
+    public User2(Integer id, String name, String email) {
+        this.name = name;
+        this.id = id;
+        this.email = email;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public Integer getId() {
+        return id;
+    }
+
+    public void setId(Integer id) {
+        this.id = id;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+}
+
+class Loan {
+
+    private Map<Integer, List<String>> loans;
+
+    public Loan() {
+        this.loans = new HashMap<>();
+    }
+
+    public void loanBook(User2 user, Book book) {
+        if (book.getCopies() > 0) {
+            book.setCopies(book.getCopies() - 1);
+            List<String> booksUser = loans.get(user.getId()) != null ? loans.get(user.getId()) : new ArrayList<>();
+            booksUser.add(book.getTitle());
+            loans.put(user.getId(), booksUser);
+        }
+
+    }
+
+    public void returnBook(User2 user, Book book) {
+        boolean exist = this.loans.get(user.getId()).stream().anyMatch(b -> b.equals(book.getTitle()));
+        if (exist) {
+            book.setCopies(book.getCopies() + 1);
+            this.loans.get(user.getId()).remove(book.getTitle());
+        }
+    }
+
+    public Map<Integer, List<String>> getLoans() {
+        return loans;
+    }
+
+    @Override
+    public String toString() {
+        return "Loan [loans=" + loans.toString() + "]";
+    }
+
+
+
+}