function UrlParams() {
    this.params = new StringBuffer();
}

UrlParams.prototype.add = function(name, value) {
    if(!this.params.isEmpty()) {
        this.params.append('&');
    }
    this.params.append(encodeURIComponent(name));
    this.params.append('=');
    this.params.append(encodeURIComponent(value));
}

UrlParams.prototype.toString = function() {
    return this.params.toString();
}