From 92f82ba270dabd588ba76f06b5832d1b6650fc41 Mon Sep 17 00:00:00 2001
From: Seungkeun Lee <sngn.lee@samsung.com>
Date: Mon, 7 Dec 2015 14:24:33 +0900
Subject: [PATCH] Add Example for Object-oriented-programming

 - How to make class
 - How to make sub class
 - How to make private property

Change-Id: Ic1a67cf893d733ce950e50b20a34e39d125494f3
---
 .../how-to-oop/how-to-implement-inheritance.js     | 46 ++++++++++++++++++++++
 examples/how-to/how-to-oop/how-to-make-class.js    | 42 ++++++++++++++++++++
 .../how-to-oop/how-to-make-private-property.js     | 28 +++++++++++++
 3 files changed, 116 insertions(+)
 create mode 100755 examples/how-to/how-to-oop/how-to-implement-inheritance.js
 create mode 100755 examples/how-to/how-to-oop/how-to-make-class.js
 create mode 100755 examples/how-to/how-to-oop/how-to-make-private-property.js

diff --git a/examples/how-to/how-to-oop/how-to-implement-inheritance.js b/examples/how-to/how-to-oop/how-to-implement-inheritance.js
new file mode 100755
index 0000000..c3d3a05
--- /dev/null
+++ b/examples/how-to/how-to-oop/how-to-implement-inheritance.js
@@ -0,0 +1,46 @@
+"use strict";
+
+var Person = require('./how-to-make-class.js');
+
+class Employee extends Person {
+  constructor(given, family, company) {
+    super(given, family);
+    this.company = company;
+  }
+
+  // method override
+  getGreetings() {
+    var msg = super.getGreetings();
+    msg += " in " + this.company;
+    return msg;
+  }
+
+  getBonus() {
+    return false;
+  }
+}
+
+class President extends Employee {
+  getBonus() {
+    return true;
+  }
+}
+
+module.exports = { 'Employee':Employee,
+                   'President':President };
+
+if (require.main === module) {
+  // Test code
+  var john = new Employee('John', 'Peter', 'Samsung');
+  console.log(john.name);
+  console.log(john.getGreetings());
+  console.log('My bonus is ' + john.getBonus());
+
+  var vp = new President('Mike', 'Park', 'Samsung');
+  console.log(vp.name);
+  console.log(vp.getGreetings());
+  console.log('My bonus is ' + vp.getBonus());
+
+  console.log("People count : " + Person.howManyPeople());
+
+}
diff --git a/examples/how-to/how-to-oop/how-to-make-class.js b/examples/how-to/how-to-oop/how-to-make-class.js
new file mode 100755
index 0000000..216275d
--- /dev/null
+++ b/examples/how-to/how-to-oop/how-to-make-class.js
@@ -0,0 +1,42 @@
+"use strict";
+
+// ES6 class reference
+// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes
+
+var people_count = 0;
+
+class Person {
+  constructor(given, family) {
+    this.given = given;
+    this.family = family;
+    people_count++;
+  }
+
+  // property getter
+  get name() {
+    return this.given + ', ' + this.family;
+  }
+
+  getGreetings() {
+    return "Hello, My name is "+ this.name;
+  }
+
+  static howManyPeople() {
+    return people_count;
+  }
+};
+
+module.exports = Person;
+
+if (require.main === module) {
+  // Test code
+  var john = new Person('John', 'Peter');
+  console.log(john.name);
+  console.log(john.getGreetings());
+
+  var park = new Person('John', 'Park');
+  console.log(park.name);
+  console.log(park.getGreetings());
+
+  console.log("People count : " + Person.howManyPeople());
+}
diff --git a/examples/how-to/how-to-oop/how-to-make-private-property.js b/examples/how-to/how-to-oop/how-to-make-private-property.js
new file mode 100755
index 0000000..7be441a
--- /dev/null
+++ b/examples/how-to/how-to-oop/how-to-make-private-property.js
@@ -0,0 +1,28 @@
+"use strict";
+
+var my_secret_key = Symbol();
+var my_secret_function = Symbol();
+
+class Secret {
+  constructor() {
+    this[my_secret_key] = Math.random()*100;
+    this[my_secret_function] = function(args) {
+      console.log('orignal data is = '+ args);
+    }
+  }
+
+  GetUserSecretKey(data) {
+    this[my_secret_function](data);
+    var crypto = require('crypto');
+    var sha1 = crypto.createHash('sha1').update(data + this[my_secret_key]);
+    return sha1.digest("hex");
+  }
+
+}
+
+module.exports = Secret;
+
+if (require.main === module) {
+  var obj = new Secret();
+  console.log(obj.GetUserSecretKey('hello'));
+}
-- 
2.7.4