1,HTML source code£º
<![CDATA[
<html>
<head>
<title>How to use NullPointerException</title>
</head>
<body>
<script src="jsjava.js"></script>
<script>
var h=new Hashtable();
try{
h.put(null,"value");
}catch(e){
document.write(e.message);
}
</script>
</body>
</html>
]]>
2,The display text is:
key and value can not be null