在web.xml中加入以下内容即可:
<error-page>
<error-code>404</error-code>
<location>/404.html</location>
</error-page>
====================================== 404.html ======================================
<!DOCTYPE html>
<html>
<title>Nothing found</title>
<style type="text/css">
img {
position: absolute;
left: 50%;
top: 50%;
margin-left: -200px;
margin-top: -209px;
}
</style>
<body>
<img src="images/404.jpg" />
</body>
</html>