谁能帮我看下为什么 dynatree这段代码不执行。缺少js文件吗》？

$("#classifyNumTree").dynatree("getTree").options.minExpandLevel = 8;
$("#classifyNumTree").dynatree("getTree").options.initAjax.data = DATA;
$("#classifyNumTree").dynatree("getTree").reload();
/////////////////////////////////////////////
Uncaught ReferenceError: jQuery is not defined jquery.contextMenu.min.js:1
Uncaught ReferenceError: jQuery is not defined jquery.cookie.min.js:10
Uncaught ReferenceError: jQuery is not defined jquery.dynatree.min.js:1555
Uncaught TypeError: Object # has no method 'dynatree'

jQuery is not defined

jquery没有成功导入，检查你的jquery路径