java - <form action="/sampleServlet" giving me exception

Question

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Answer 1

When you are using URL in HTML, without leading / they are relative to the current URL (ie current page displayed). With leading / they are relative to the website root :

<form action="/context-path/sampleServlet">

or

<form action="sampleServlet">

will do what you want.

I suggest you to add the context inside the action path dynamically. Example (in JSP) :

<form action="${pageContext.request.contextPath}/sampleServlet">

With this you will never have to change the path, for example, if you move your file or copy your code, or rename your context!