JScript TinyCache for Classic ASP

TinyCache.js

// Author : wangye
// For more information please visit http://wangye.org/blog/archives/706/
var RawCache = function() {
    this.setItem = function(key, value) {
        Application.Lock();
        Application.Contents(key) = value;
        Application.Unlock();
    };
 
    this.getItem = function(key, defvalue) {
        value = Application.Contents(key);
        return typeof(value) != 'undefined' ? value : defvalue;
    };
 
    this.remove = function(key) {
        Application.Lock();
        Application.Contents.Remove(key);
        Application.Unlock();
    };
 
    this.isAvailable = function() {
        return true;
    };
}
 
var TinyCache = function(name, useStaticObjects) {
    if (useStaticObjects) {
        this.cache = Application.StaticObjects(name);
    }
 
    if (!this.cache) {
        this.raw_cache = new RawCache();
        this.cache = this.raw_cache.getItem(name, null);
 
        if (this.cache != null) {
            this.cache = this.cache.getItem(0);
        } 
 
        if (!this.cache || typeof this.cache != "object") {
            this.mem = Server.CreateObject("Scripting.Dictionary");
            var msscript = Server.CreateObject("MSScriptControl.ScriptControl");
            msscript.Language = "VBScript";
            msscript.AllowUI = false;
            msscript.AddObject("SafeVBArrayValue", this.mem);
            this.raw_cache.setItem(name, msscript.Eval("Array(SafeVBArrayValue)"));
            this.cache = this.raw_cache.getItem(name, null).getItem(0);
        }
    }
 
    this.setItem = function(key, value) {
        if (this.cache.Exists(key)) {
            var prevalue = this.cache.Item(key);
            this.cache.Item(key) = value;
            return prevalue;
        } else {
            this.cache.Add(key, value);
            return null;
        }
    };
 
    this.getItem = function(key, defvalue) {
        if (this.cache.Exists(key)) {
            return this.cache.Item(key);
        } else {
            return defvalue;
        }
    };
 
    this.remove = function(key) {
        if (this.cache.Exists(key)) {
            this.cache.Remove(key);
        }
    };
 
    this.contains = function(key) {
        return this.cache.Exists(key);
    };
 
    this.isAvailable = function() {
        return true;
    };
}