Here is how my WebFilter
looks like
@WebFilter("/rest/*")
public class AuthTokenValidatorFilter implements Filter {
@Override
public void init(final FilterConfig filterConfig) throws ServletException {
}
@Override
public void doFilter(final ServletRequest servletRequest, final ServletResponse servletResponse, final FilterChain filterChain) throws IOException, ServletException {
final Enumeration<String> attributeNames = servletRequest.getAttributeNames();
while (attributeNames.hasMoreElements()) {
System.out.println("{attribute} " + servletRequest.getParameter(attributeNames.nextElement()));
}
final Enumeration<String> parameterNames = servletRequest.getParameterNames();
while (parameterNames.hasMoreElements()) {
System.out.println("{parameter} " + servletRequest.getParameter(parameterNames.nextElement()));
}
filterChain.doFilter(servletRequest, servletResponse);
}
@Override
public void destroy() {
}
}
I tried to find out online as to how to get values for HTTP headers
coming from request.
I did not find anything, so I tried to enumerate on servletRequest.getAttributeNames()
and servletRequest.getParameterNames()
without knowing anything, but I do not get any headers.
Question
How can I get all the headers coming from the request?
Typecast ServletRequest
into HttpServletRequest
(only if ServletRequest request
is an instanceof
HttpServletRequest
).
Then you can use HttpServletRequest.getHeader()
and HttpServletRequest.getHeaderNames()
method.
Something like this:
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
HttpServletRequest httpRequest = (HttpServletRequest) request;
Enumeration<String> headerNames = httpRequest.getHeaderNames();
if (headerNames != null) {
while (headerNames.hasMoreElements()) {
System.out.println("Header: " + httpRequest.getHeader(headerNames.nextElement()));
}
}
//doFilter
chain.doFilter(httpRequest, response);
}