jsface

Small, fast, elegant, powerful, and cross platform JavaScript OOP library. Support main, singleton, super call, private, mixins, plugins, AOP and more.

Features

• Small footprint, no dependency, 0.7K minimized+gzip!
• Super fast! See benchmark.
• Work on both server and client side.
• Support CommonJS.
• Support main, singleton, mixin, private properties, Aspect Oriented Programming.
• Plugins mechanism to extend itself.

Setup

JSFace supports both server side (CommonJS) and client side JavaScript (browser).

Browser:

<script src="jsface.js" type="text/javascript"></script>

JSFace introduces two global variables: jsface and Class. Other APIs are under jsface namespace.

In NodeJS environment, first install JSFace via npm:

npm install jsface

Then use its APIs, for example:

var jsface = require("jsface"),
    Class  = jsface.Class,
    extend = jsface.extend;

API

Define a class

var Person = Class({
  constructor: function(name, age) {
    this.name = name;
    this.age  = age;
  },
 
  toString: function() {
    return this.name + "/" + this.age;
  }
});
 
var person = new Person("Rika", 20);
person.toString();                               // "Rika/20" 

Define a sub-class

var Student = Class(Person, {
  constructor: function(id, name, age) {
    this.id = id;
    Student.$super.call(this, name, age);    // Invoke parent's constructor 
  },
 
  toString: function() {
    return this.id + "/" + Student.$superp.toString.call(this); // Invoke parent's toString method 
  }
});
 
var student = new Student(1, "Rika", 20);
student.toString();                              // "1/Rika/20" 

main

JSFace supports a special method named main(). main() is executed right after the class is created.

Class({
  constructor: function(name) {
    this.name = name;
  },
 
  getName: function() {
    return this.name;
  },
 
  main: function(Person) {                       // Class is passed to main() as its first argument 
    var p = new Person("Rika");
 
    p.getName();                                 // "Rika" 
  }
});

Singleton class

var Util = Class({
  $singleton: true,
 
  echo: function(obj) {
    return obj;
  }
});
 
Util.echo(2012);                                 // 2012 

Static properties

JSFace supports Java-style static properties. Meaning they are accessible on both class and instance levels.

var Person = Class({
  $statics: {
    MIN_AGE:   1,
    MAX_AGE: 150,
 
    isValidAge: function(age) {
      return age >= this.MIN_AGE && age <= this.MAX_AGE;
    }
  },
 
  constructor: function(name, age) {
    this.name = name;
    this.age  = age;
  }
});
 
var person = new Person("Rika", 20);
 
Person.MIN_AGE === person.MIN_AGE;               // true 
Person.MAX_AGE === person.MAX_AGE;               // true 
Person.isValidAge(0);                            // false 
person.isValidAge(person.age);                   // true 

Private properties

JSFace supports private static properties, meaning the properties are shared over instances.

var Person = Class(function() {
  var MIN_AGE =   1,                             // private variables 
      MAX_AGE = 150;
 
  function isValidAge(age) {                     // private method 
    return age >= MIN_AGE && age <= MAX_AGE;
  }
 
  return {
    constructor: function(name, age) {
      if ( !isValidAge(age)) {
        throw "Invalid parameter";
      }
 
      this.name = name;
      this.age  = age;
    }
  };
});

Mixins

JSFace provides a powerful mechanism to support mixins. Reusable code can be mixed into almost anything.

Mixin can be bound when you define classes:

var Options = Class({
  setOptions: function(opts) {
    this.opts = opts;
  }
});
 
var Events = Class({
  bind: function(event, fn) {
    return true;
  },
  unbind: function(event, fn) {
    return false;
  }
});
 
var Person = Class({
  constructor: function(name, age) {
    this.name = name;
    this.age  = age;
  }
});
 
// Student inherits Person and extends properties from Options and Events 
var Student = Class([ Person, Options, Events ], {
  constructor: function(id, name, age) {}
});
 
var student = new Student(1, "Rika", 20);
student.setOptions({ foo: true });               // student.opts === { foo: true } 
student.bind();                                  // true 
student.unbind();                                // false 

Or after defining classes:

var Student = Class(Person, {
  constructor: function(id, name, age) {
});
 
extend(Student, [ Options, Events ]);

Mixin with instance:

var person = new Person("Rika", 20);
 
extend(person, Options);
person.setOptions({ foo: true });

Mixin with native classes:

extend(String.prototype, {
  trim: function() {
    return this.replace(/^\s+|\s+$/g, "");
  }
});
 
"   Hello World    ".trim();                     // "Hello World" 

No conflict

In browser environment, you might be using another library which also introduces the global namespace Class. JSFace can return the original Class back to the library claims it with a call to jsface.noConflict().

jsface.noConflict();
 
// Code that uses other library's Class can follow here 
// ... 
 
// Define classes by using jsface.Class directly 
var Person = jsface.Class({
});

Plugins

Plug and Play pointcut

JSFace supports Aspect Oriented Programming (AOP) via simple before/after mechanism. You can apply pointcuts over class constructors, class methods, singleton methods, instance methods. You can even apply pointcuts over native classes.

AOP support is implemented as a standalone plugin.

Setup

Browser:

<script src="jsface.pointcut.js" type="text/javascript"></script>

then in your code, make an alias to jsface.pointcut:

var pointcut = jsface.pointcut;

NodeJS:

var pointcut = require("jsface.pointcut");

Applying pointcuts

In JSFace, an advisor is a set of pointcuts you want to apply to a subject. You can apply as many advisors as you want.

Person = Class({
  constructor: function(name) {
    this.name    = name;
    this.counter = 0;
  },
  foo: function(n) {
  },
  bar: function(n) {
  }
});
 
var advisor = {
  constructor: {
    before: function() {
      this.age = 20;
    },
    after: function() {
      this.email = "rika@sample.com";
    }
  },
  foo: function(n) {                             // sugar syntax, foo:before 
    this.counter++;
  },
  bar: {
    before: function(n) {
      this.counter++;
    },
    after: function(n) {
      this.counter++;
    }
  }
};
 
Person = pointcut(Person, advisor);
 
var person = new Person("Rika");
 
person.foo();
person.bar();
 
person.name    === "Rika";                       // true 
person.age     === 20;                           // true 
person.email   === "rika@sample.com";            // true 
person.counter === 3;                            // true 

Removing pointcuts

Using previous apply pointcut example:

// remove all pointcuts bound to constructor and foo 
Person = poincut(Person, "remove constructor foo");
 
// remove advisor, other advisors remained 
Person = poincut(Person, "remove", advisor);
 
// remove all advisors, restore the fresh version of Person 
Person = poincut(Person, "remove");

$ready

$ready plugin is designed to help parent classes to intercept their subclasses' creation. If a class uses $ready, it notifies itself.

Setup

Browser:

<script src="jsface.ready.js" type="text/javascript"></script>

NodeJS:

var ready = require("jsface.ready");

Sample

var Service = Class({
  $ready: function(clazz, parent, api) {
    var type = (this !== clazz) && api.type;
 
    switch (type) {
      case "session":
        // do something with subclass clazz when its type is session 
        break;
      case "application":
        // do something with subclass clazz when its type is application 
        break;
    }
  }
});
 
var SessionService = Class(Service, {
  type: "session"
});
 
var ApplicationService = Class(Service, {
  type: "application"
});

Bug tracker

Have a bug? Please create an issue here on GitHub!

License

Copyright (c) 2009-2013 Tan Nhu

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.