Merge pull request #7266 from danhingar/ejercicio23

#23 - Java

Author: kontroldev

Roadmap/23 - SINGLETON/java/danhingar.java

@@ -0,0 +1,221 @@
+public class danhingar {
+
+    public static void main(String[] args) {
+        // Definición de singleton como clase
+        SinglentonClass singlentonClass1 = SinglentonClass.getInstance();
+        System.out.println(singlentonClass1.hashCode());
+
+        SinglentonClass singlentonClass2 = SinglentonClass.getInstance();
+        System.out.println(singlentonClass2.hashCode());
+
+        System.out.println(singlentonClass1 == singlentonClass2);
+
+        // Definición de singleton como enumerado
+        SinglentonEnum singlentonEnum1 = SinglentonEnum.INSTANCE.getInstance();
+        System.out.println(singlentonEnum1.hashCode());
+
+        SinglentonEnum singlentonEnum2 = SinglentonEnum.INSTANCE.getInstance();
+        System.out.println(singlentonEnum2.hashCode());
+
+        System.out.println(singlentonEnum1 == singlentonEnum2);
+
+        // Extra
+        UserSession userSession1 = UserSession.getInstance();
+        userSession1.login(1, "user1", "Pepe", "[email protected]");
+        System.out.println(userSession1.toString());
+
+        UserSession userSession2 = UserSession.getInstance();
+        System.out.println(userSession2.toString());
+
+        UserSession userSession3 = UserSession.getInstance();
+        userSession3.logout();
+        System.out.println(userSession3.toString());
+        System.out.println(userSession2.toString());
+        System.out.println(userSession1.toString());
+
+        UserSessionEnum userSession4 = UserSessionEnum.INSTANCE.getInstance();
+        userSession4.login(2, "user2", "Juan", "[email protected]");
+
+        System.out.println("Session 4"+userSession4.toString());
+
+        UserSessionEnum userSession5 = UserSessionEnum.INSTANCE.getInstance();
+        userSession4.login(3, "user3", "Mateo", "[email protected]");
+        System.out.println("Session 4"+userSession4.toString());
+        System.out.println("Session 5"+userSession5.toString());
+
+        UserSessionEnum userSession6 = UserSessionEnum.INSTANCE.getInstance();
+        userSession6.logout();
+        System.out.println("Session 4"+userSession4.toString());
+        System.out.println("Session 5"+userSession5.toString());
+        System.out.println("Session 6"+userSession6.toString());
+    }
+
+}
+
+class SinglentonClass {
+
+    private static SinglentonClass INSTANCE;
+
+    private SinglentonClass() {
+
+    }
+
+    public static SinglentonClass getInstance() {
+        if (INSTANCE == null) {
+            INSTANCE = new SinglentonClass();
+        }
+
+        return INSTANCE;
+    }
+}
+
+enum SinglentonEnum {
+    INSTANCE();
+
+    public SinglentonEnum getInstance() {
+        return INSTANCE;
+    }
+
+    private SinglentonEnum() {
+    }
+
+}
+
+// EXTRA
+class UserSession {
+    private static UserSession INSTANCE;
+    private Integer id;
+    private String username;
+    private String name;
+    private String email;
+
+    private UserSession() {
+    }
+
+    public static UserSession getInstance() {
+        if (INSTANCE == null) {
+            INSTANCE = new UserSession();
+        }
+
+        return INSTANCE;
+    }
+
+    public Integer getId() {
+        return id;
+    }
+
+    public void setId(Integer id) {
+        this.id = id;
+    }
+
+    public String getUsername() {
+        return username;
+    }
+
+    public void setUsername(String username) {
+        this.username = username;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+    public void login(Integer id, String username, String name, String email) {
+        this.id = id;
+        this.username = username;
+        this.name = name;
+        this.email = email;
+    }
+
+    @Override
+    public String toString() {
+        return "Session [id=" + id + ", username=" + username + ", name=" + name + ", email=" + email + "]";
+    }
+
+    public void logout() {
+        this.id = null;
+        this.username = null;
+        this.name = null;
+        this.email = null;
+    }
+
+}
+
+enum UserSessionEnum {
+    INSTANCE();
+
+    private Integer id;
+    private String username;
+    private String name;
+    private String email;
+
+    public UserSessionEnum getInstance() {
+        return INSTANCE;
+    }
+
+    private UserSessionEnum() {
+    }
+
+    public Integer getId() {
+        return id;
+    }
+
+    public void setId(Integer id) {
+        this.id = id;
+    }
+
+    public String getUsername() {
+        return username;
+    }
+
+    public void setUsername(String username) {
+        this.username = username;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+    public String toString() {
+        return " [id=" + id + ", username=" + username + ", name=" + name + ", email=" + email + "]";
+    }
+    
+    public void logout() {
+        this.id = null;
+        this.username = null;
+        this.name = null;
+        this.email = null;
+    }
+
+    public void login(Integer id, String username, String name, String email) {
+        this.id = id;
+        this.username = username;
+        this.name = name;
+        this.email = email;
+    }
+
+}