Merge pull request mouredev#7114 from Josegs95/main

#23 y #24 - Java

Author: kontroldev

Roadmap/23 - SINGLETON/java/Josegs95.java

@@ -0,0 +1,99 @@
+public class Josegs95 {
+    public static void main(String[] args) {
+        //Ejercicio
+        Singleton s1 = Singleton.getInstance("1");
+        Singleton s2 = Singleton.getInstance("2");
+
+        System.out.println("Si tienen el mismo 'id', es la misma instancia:");
+        System.out.println(s1.getId());
+        System.out.println(s2.getId());
+
+        //Reto
+        retoFinal();
+    }
+
+    public static void retoFinal(){
+        Session session1 = Session.getInstance();
+        session1.setUser("1", "Josegs95", "Jose", "[email protected]");
+
+        System.out.println(session1);
+
+        Session session2 = Session.getInstance();
+
+        System.out.println(session2);
+
+        session2.clear();
+
+        System.out.println(session1);
+    }
+
+    public static class Singleton{
+        private static Singleton instance;
+        private String id;
+
+        private Singleton(String id){
+            this.id = id;
+        }
+
+        public static Singleton getInstance(String id){
+            if (instance == null)
+                instance = new Singleton(id);
+            return instance;
+        }
+
+        public String getId(){
+            return id;
+        }
+    }
+
+    public static class Session{
+        private static Session session;
+        private String id;
+        private String username;
+        private String name;
+        private String email;
+
+        private Session() {}
+
+        public static Session getInstance(){
+            if (session == null)
+                session = new Session();
+            return session;
+        }
+
+        public void setUser(String id, String username, String name, String email){
+            this.id = id;
+            this.username = username;
+            this.name = name;
+            this.email = email;
+        }
+
+        public String getId() {
+            return id;
+        }
+
+        public String getUsername() {
+            return username;
+        }
+
+        public String getName() {
+            return name;
+        }
+
+        public String getEmail() {
+            return email;
+        }
+
+        public void clear(){
+            id = null;
+            username = null;
+            name = null;
+            email = null;
+        }
+
+        @Override
+        public String toString() {
+            return "[" + id + ", " + username + ", " + name + ", " + email + "]";
+        }
+    }
+}

Roadmap/24 - DECORADORES/java/Josegs95.java

@@ -0,0 +1,82 @@
+public class Josegs95 {
+    public static void main(String[] args) {
+        //Ejercicio
+        //En java es un poco engorroso los decoradores porque necesitas muchas clases
+        //e interfaces para implementar el patrón de diseño
+        Interface instance1 = new DefaultImplClass();
+        System.out.println(instance1.getString());
+
+        Interface instance2 = new Decorator(new DefaultImplClass());
+        System.out.println(instance2.getString());
+
+        //Reto
+        retoFinal();
+    }
+
+    public static void retoFinal(){
+        //Voy a reutilizar la interfaz y las clases usadas en el ejercicio para evitar
+        //crear demasiado código "dummy"
+        Interface instance = new ChallengeDecorator(new DefaultImplClass());
+
+        System.out.println("Veces que se ha llamado a 'getString()': " + ((ChallengeDecorator)instance).getCounter());
+        instance.getString();
+        instance.getString();
+        instance.getString();
+        System.out.println("Veces que se ha llamado a 'getString()': " + ((ChallengeDecorator)instance).getCounter());
+    }
+
+    public interface Interface{
+        String getString();
+    }
+
+    public static class DefaultImplClass implements Interface{
+        @Override
+        public String getString() {
+            return "Cadena por defecto";
+        }
+    }
+
+    public static abstract class BaseDecorator implements Interface{
+        private Interface interfaceInstance;
+
+        public BaseDecorator(Interface interfaceInstance) {
+            this.interfaceInstance = interfaceInstance;
+        }
+
+        @Override
+        public String getString() {
+            return interfaceInstance.getString();
+        }
+    }
+
+    public static class Decorator extends BaseDecorator{
+        public Decorator(Interface interfaceInstance) {
+            super(interfaceInstance);
+        }
+
+        @Override
+        public String getString() {
+            return super.getString() + ", mas la cadena del decorador";
+        }
+    }
+
+    public static class ChallengeDecorator extends BaseDecorator{
+
+        private int counter;
+
+        public ChallengeDecorator(Interface interfaceInstance) {
+            super(interfaceInstance);
+            counter = 0;
+        }
+
+        @Override
+        public String getString() {
+            counter++;
+            return super.getString();
+        }
+
+        public int getCounter() {
+            return counter;
+        }
+    }
+}