Uberclass
Uberclass is a class framework based on JavaScriptMVC $.Class and John Resig's Simple JavaScript inheritance for NodeJS. It encourages a hybrid approach between functional and object oriented programming.
Features:
- Prototypal inheritance
- Static inheritance
- Setup and initialization methods
- Easy callback creation
Install and require
You can either use npm
npm install uberclass
Or clone the github repository.
Creating a Class
The following creates a Monster class with static, and prototype members. The prototype init is called as the constructor. Every time a monster instance is created, the static count is incremented:
var Class = require('uberclass');
var Monster = Class.extend(/* @static */ {
count: 0
},
/* @prototype */
{
init: function( name ) {
// saves name on the monster instance
this.name = name;
// sets the health
this.health = 10;
// increments count
this.Class.count++;
},
eat: function( smallChildren ){
this.health += smallChildren;
},
fight: function() {
this.health -= 2;
}
});
hydra = new Monster('hydra');
dragon = new Monster('dragon');
console.log(hydra.name) // -> hydra
console.log(Monster.count) // -> 2
hydra.eat(2);
console.log(hydra.health); // health = 12
dragon.fight();
console.log(dagon.health); // health = 8
Inheritance
When a class is extended, all static and prototype properties are available on the new class. If you overwrite a function, you can call the base class's function by calling this._super. Lets create a SeaMonster class. SeaMonsters are less efficient at eating small children, but more powerful fighters.
var SeaMonster = Monster.extend({
eat : function(smallChildren)
{
this._super(smallChildren / 2);
},
fight : function()
{
this.health -= 1;
}
});
var lochNess = new SeaMonster('Loch Ness');
lochNess.eat(4);
console.log("Loch Ness ate. Health: " + lochNess.health); // -> 12
lochNess.fight();
console.log("Loch Ness fought. Health: " + lochNess.health); // -> 11
Callbacks
Class provides a proxy function that returns a callback to a method that will always have this set to the class or instance of the class. The following example creates a ResponseHandler class that takes the reponse text and the responses header options as constructor arguments and provides it's handle method as a callback to the http.createServer function:
var Handler = Class.extend({
init : function(content, headers)
{
this._headers = headers;
this._content = content;
},
/* Prototype */
writeHead : function(response)
{
response.writeHead(200, this._headers);
},
handle : function(request, response)
{
this.writeHead(response);
response.end(this._content);
}
});
var handler = new Handler('Hello World from ResponseHandler\n', { 'Content-Type': 'text/plain' });
var http = require('http');
http.createServer(handler.proxy('handle')).listen(1337, "127.0.0.1");
Exporting
Just add the class object to your module export:
// my_module.js
module.exports.MyClass = Class.extend({ /* Static */ }, { /* Prototype */ });