public String getPara(int index) {
		if (index < 0)
			return getPara();
		
		if (urlParaArray == null) {
			if (urlPara == null || "".equals(urlPara))	// urlPara maybe is "" see ActionMapping.getAction(String)
				urlParaArray = NULL_URL_PARA_ARRAY;
			else
				urlParaArray = urlPara.split(URL_PARA_SEPARATOR);
			
			for (int i=0; i<urlParaArray.length; i++)
				if ("".equals(urlParaArray[i]))
					urlParaArray[i] = null;
		}
		return urlParaArray.length > index ? urlParaArray[index] : null;
	}
public String getPara ( int index ) { if ( index < 0 ) return getPara ( ) ; if ( urlParaArray == null ) { if ( urlPara == null || "" . equals ( urlPara ) ) urlParaArray = NULL_URL_PARA_ARRAY ; else urlParaArray = urlPara . split ( URL_PARA_SEPARATOR ) ; for ( int i = 0 ; i < urlParaArray . length ; i ++ ) if ( "" . equals ( urlParaArray [ i ] ) ) urlParaArray [ i ] = null ; } return urlParaArray . length > index ? urlParaArray [ index ] : null ; }
Get para from url. The index of first url para is 0.