var cnt = 0;

window.onload = function() {
	var _slist = document.getElementsByTagName("span");
	
	for(var i = 0; i< _slist.length; i++){
		var _cl = Element.classNames(_slist[i]);
		if(_cl == "caption"){
			//alert(_slist[i].firstChild.nodeValue);
			execute(_slist[i], _slist[i].firstChild.nodeValue);
		}
	}
}


String.prototype.getExtent = function(ruler) {
	var e = $(ruler);
	var c;
	while (c = e.lastChild) e.removeChild(c);
	var text = e.appendChild(document.createTextNode(this));
	var width = e.offsetWidth;
	e.removeChild(text);
	return width;
}

String.prototype.truncateTailInWidth = function(maxWidth, ruler) {
	if (this.length == 0) return '';
	if (this.getExtent(ruler) <= maxWidth) return this;
	for (var i=this.length-1; i>=1; --i) {
		var s = this.slice(0, i) + '...';
		if (s.getExtent(ruler) <= maxWidth) return s;
	}
	return '';
}

function execute(_tar, _str) {
	var resultStr = _str.truncateTailInWidth(141,'ruler');
	_tar.firstChild.nodeValue = resultStr;
}